Hello,
i have recently purchased a 91 75 twin spark for what seems like not much money..... However, it has a couple of minor (i hope) issues. They are:
its down on power but really sings above 5000k (i suspect VVT isnt working)
engine/prop shaft vibration at and just above idle (950-2000 rpm)
gearbox oil leak
rusty drivers side headlight
power steering belt idler pulley noisy
one coil leaking spark
some creaks in the front suspension when braking to a standstill
Having gone through a similar process recently with a TS powered berlina (thanks Julian) I am not too concerned about the motor. My plan is to check the ecu fault codes then work through things methodically - valve clearance, timing, plugs, leads, caps and rotors, and to pull apart, test and clean the Motronic bits on the intake.
My main concern is the prop shaft vibration.... I will have a chance to inspect things properly this weekend and would appreciate tips on what to inspect or do to isolate the source of the vibration. Also, as the car has done 270,000kms (with a full service history), what should i replace for piece of mind?
At idle, if you push the clutch in, it should be smooth. Clutch out, you are spinning the entire length of shaft plus the clutch and it is usually not so smooth.Check all 3 donuts and centre mount bearing in the prop shaft, for cracks and wear. I bet they will be wore and cracked unless changed recently. If in doubt, change them all. When taking the shaft out, mark and align everything so it does back in the same orientation.
You can get the donuts and bearing from the usual local suppliers but make sure you get ones for the 75.
Check all the nuts connecting the donuts are tight.
This could be a starter.
It will depend, as Neil said, what's been changed before. But in general, there'a many parts that are subject to wear and may benefit from replacement:
front suspension: lower control arm bushes, upper control arm bush, steering knuckle balljoints, tie rod ends
rear suspension: De Dion bush, Watt's linkage bushes
mounts: engine mounts x3, transaxle mounts x3
prop shaft: donuts x3, centre support + bearing
I would personally change the donuts and centre support, and all the engine mounts and transaxle mounts at a minimum, unless you can be sure they are in top condition.
Also change all fluids and if necessary the brake pads and discs of course.
:)
I'm not familiar with the 2.0 engine, sorry, so can't advise there.
The donuts look ok. Can't really tell about the centre mount. I found my centre mount to be perished, and replacement will hopefully remove the small vibrations I noticed.
http://pic20.picturetrail.com/VOL166/13567593/24504607/408631939.jpg
You may still need to remove the prop shaft to be certain.
I guess you have to decide if you're wanting to do things as quickly and cheaply as possible (ie: replace only what is required), or have the time to have the car off the road for a period, and replace everything regardless, to make the car fresh, particularly if you plan to keep it for a long time.
Enjoy. :)
Thanks SC, that center support does look bad! Nice build thread too!
I think that the minimum will be done immediately for rwc and then a major teardown in the next 12 months. The car has a full service history with benincas and everywhere I am finding evidence of of a well maintained car. The exception would be some of the oil leaks...
I haven't been able to check the ecu fault codes yet as the loom has a different diagnostics port to the Berlina. It's located under the dash but doesn't have all of the wire colours as described in a post by festy in this thread
http://www.alfabb.com/bb/forums/milano-75-1985-1993/206535-ts-engine-issues.html
Specifically I can't find the blue and yellow wire.
I will need to replace the drive shaft seals at the differential. Is this a big job?
Ive had a thought.... the fuel quality plug (blue) would enable closed loop control of the mixture. With a missfire would the lamda sensor become fouled? I can test by removing the fuel quality plug to enable open loop control.
If the plugs are wet and fouling, they may be too cold and you need a warmer plug to run hotter and burn off all the crap, is your thermostat working properly?, if the engine is running too cold, then the engine temperature will be too cold, as will the spark plugs, and they won't get hot enough, Colin.
Thanks col, I have my doubts about the thermostat. Indicated coolant temp sits at around 70 but as ambient temp goes down so does coolant temp, as low as 60... It's on the list of things to check. I put ngk 6s in it to replace champion 9s.
I have figured out the wiring of the late style diagnostics port. The thing that threw me was the wiring colour for the diagnostics switch.... Instead of blue and yellow it's blue with white stripes (page 38 to 40 of section E of the workshop manual)
Remember you have a fully working TS to steal parts from! If you are suspect of a part, swap it with a known working one (i.e from the Berlina), but do it one at a time to make sure you isolate.
I am running NGK FR5 spark plugs in both TS motors and have only fouled plugs once and there were many issues leading up to that.
As I understand the O2 sensor; if the ECU detects an issue it just starts to ignore it. It is also not used at idle or WOT. Idle because the gasses are not hot enough to give a consistent reading and WOT because the program is set to a different ratio (12.5 as compared to lambda - 14.7).
Pulling the fuel quality plug often exacerbates an idle issue in my experience. Also, when you do pull it out, the engines seems to have to relearn a bit so take it for a good drive on open road (shouldn't be too hard for you!). Sometimes when I switch between the two settings (91 and 98) it will stall and run poorly for a little while till it learns the new program.
The thermostat shouldn't be an issue. My GTV had a partially open Tstat all summer and ran fine. I finally replaced it because the heater was taking too long on the cold morning/nights! I sourced one from www.alfa-service.com
They are a little short on notifications but both times I have ordered through them the part has just arrived a week later.
Sorry, I was working off memory (and google) with my plug choice. They are actually Bosch FR5DC.
I've swapped where possible leads and dizzy caps but until the 75 is sorted i need the Berlina to get around. This limits how far i can go with part swaps. I could swap coils.... or the motors
Circumstantially i have wet something and its malfunctioned or its wrecked. Unfortunately i cant investigate the prop shaft with the motor like this.
My thermostat was removed for a full coolant flush, and it took me a while to remember to put the thermostat back, but after a plug kept fouling and being wet with petrol and not firing, i put back the stat and the engine ran hotter and the plug started firing again, Colin.
I'm not near the 75 until this evening, can someone tell me what diameter the original ht leads are? I'm thinking of making a new set to match the originals in length/diameter but to suit ngk plugs.
I'd suggest you may wish to consider Denso Iridium plugs as they come with removable threaded caps, to suit the original Twin Spark lead connector ends. As you've probably discovered the NGK recommended spark plug has fixed caps so you would need to change the leads as well. I run IK22 (part # 5310) which is one range cooler than normal as my car spends most its time on track. They definitely fixed my rough idle problem but then again I changed from the original and very worn Golden Lodge 25 HLDs.
Hope this helps and save you a few bucks along the way.
Henry.
i have measured the resistance the HT leads. The primary leads (coil to distributor) were both ~1kohm. The spark plug leads were all over the place, none lower than 11kohm but most were open circuit. I couldnt resist (ha!) the urge to pull one of the leads apart. It seems there is a resistor in the plug end of the lead (inside a red/brown bakelite sleeve, which is inside the rubber boot). Most of these seemed to have failed (ie open circuit). With this removed the leads measured the same as the primaries (~1kohm).
I'd really like to retain 7mm leads so they fit under the cover plate. any suggestions on repairing these leads (is the resistor necessary if resistor plugs are used?) or sourcing others for under 95 pounds plus postage?
as i have ruined my stuffed leads i cant troubleshoot the TS without pinching the HT leads off the berlina... a job for the weekend as the berlina needs to start at 5:30am
I have sorted the idle on the 75. None of the leads that i have are good, especially the stock, origninal 75 leads. The bosch leads on the berlina needed re-terminating to get the kohms right and the car idles nicely with these, throttle response is good. I have 2 new sets on the way.
i assume that the idle/power issues has been a ht lead issue but i have also cleaned up the engine bay earths and replaced the cable from the starter solenoid to the distribution terminal as per craigs place advice. Interestingly, with the engine running and the high beams on I measured 25 amps in this cable... glad its not 6mm2 any more... if the engine fan was on too this would be around 30 amps. Add in a heater fan and a window winder....Probably within the amperage of the cable but the voltage drop would be excessive. I would have liked to have measured the voltage at the headlamps before and after...
So its onto the other big issue... the prop shaft vibration.
i seem to have made this worse by packing the rear engine mount with rubber heater hose segments. I have removed bits from above the pin and inserted below and then removed them altogether to attempt to achieve a reduction in vibration. The PO has told me that once in the time hes's owned the car the tailshaft was rebuilt by benincas.
I'll have a rwc inspection done this week and while its on the hoist I'll try to have a go at the center mount with a pry bar and see whats soft with mounts, see if the donut centering bushes are loose. I have read that loosening certain mounts then revving the engine can realign the tailshaft/gearbox mounts. I may try this too.
Other things:
PS idler pulley bearing. This is a discontinued SKF that is very expensive NOS (probably because its used on ferraris too). Does anyone have this part left over from a 105/116 conversion (might ask this elsewhere on the forum)
Oil level sensor bypassed with a 100 ohm resistor. Not really concerned about this
Thermostat may be stuck open (will check when i replace the coolant this week)
Diff drive shaft seals leaking... May have to repair for RWC
Cam cover leaking at rear distributor blank, alot.
Steering rack boot torn
I have an idea on how to implement a DIS with the stock motronic and do away with the distributors.... I may get over it but right now i don't want to look at them!
You clearly know how to trouble shoot, which is great to see. You're more likely to be a help to others, than others being able to help you!
But keep us informed. It makes enjoyable and informative reading.
:)
Keep up the posts! I just got my TS going. Bought it for the transaxle for my 3lt, ended up being way too good to wreck so put the 3lt TA into it and now drive it to work and back. Aiming for economy, so far looking at 7.5l/100km for 1/3 town and 2/3 highway.
Still trouble shooting minor things though. Cruse control, after market central locking which won't unlock with key if it was locked by remote but of course jams locked sometimes, no heater fan etc etc.
Steering rack boots I bought a few weeks about from Bursons - $12 each.
I have a noise coming from the power steering pump myself, but noticed when I leaned on the hoses it went away.
thanks guys!
the ts with v6 transaxle would take a while to wind up! I should do that with my TS as i drive it or the Berlina to Bridgewater for work. Its about 75 kms each way and the Berlina has a 4.3 diff.... Good for overtaking though!
Jazig, howd you go with the tailshafts in your cars? Any experience with resolving vibrations? Have you had to replace engine/transmission mounts and did this create/fix vibrations? Thanks for the tip on the steering rack boots.
I was in Flowswerve a couple of weeks ago for a visit. Hows things there these days?
for troubleshooting the bosch motronic just follow the advice of Greg on his page here:
http://www.hiperformancestore.com/Motronic.htm
he refers to Beamers but most of it applies to the 75TS.
The VVT can be tested as per the alfa docs located here:
http://david.alfa-romeo.eu/alfa/AlfaRomeo75/
here are all of the docs that were hosted at craigs place (plus many more!)
For the v6 i would assume that the L-jetronic page would be equally helpful:
http://www.hiperformancestore.com/Ljetronic.htm
+1 on the denso iridium plugs - I run the same on my TS super (also need the screw thread posts for the COP units)
Also the BERU UXF56 plugs (which are a little like the lodges with four tangs instead of one - not iridium though) are a good alternative. I fitted my spare set to replace some old lodges and cured a lumpy idle.
Great to see the super-sleuth at work ;)
Might be worth borrowing and putting in a propshaft that is known to be balanced and vibration free, just to eliminate (or not) that as an issue.
What's that wagon behind the Valiant?
A volkswagen, 76 Golf project car
Quotethe ts with v6 transaxle would take a while to wind up!
It was a big shock after going from a modified 3lt with the TS box! But now that I'm used to it, it will be fine. Perfect for the run between Bendigo and Castlemaine. After one day to and from work I re-fuelled and worked it out to do 7.5lt/100km. 3lt was doing 20+/100km which included my 'fun' driving [I never tried to be efficient].
Quotehowd you go with the tailshafts in your cars? Any experience with resolving vibrations? Have you had to replace engine/transmission mounts and did this create/fix vibrations?
I've only ever had vibration from a shot doughnut which threw a chunk. I've never had problems with apparent misalignment. I actually put 3mm spacers under the TS box mounts to give the shifter clearance from the cross member after the conversion. The stock TS shifter touched the cross member, which I believe is the ball joint wear to blame. So effectively lifted the front of the box 3mm out of alignment. No vibration.
I think people show too much caution with alignment. Fair enough, take care if you can but I just think it doesn't matter THAT much.
I only bother marking the nuts and bolts if they are the Alfetta GTV type [shape and size is different, the 75's have the same nuts everywhere in my experience]. I do mark the rotation of the shaft halves if splitting it at the middle though. I've pulled my drive shaft out in the 3lt 4 or 5 times now?
QuoteI was in Flowswerve a couple of weeks ago for a visit. Hows things there these days?
Not pretty. It's a wonder how we are still open most days. We really only have one project keeping us floating from what I can tell. Production hours in the shop was running at 45% last time I heard a month ago. If anything we are worse now. I'm busy though, the rest of the machine shop is working one job to the next with a lot of cleaning in between.
On the way home today i swung into Parker St to see if a 75 was outside TKL. It wasnt... Instead i got pulled over by a friendly policeman who suggested the Berlina would look better with bumpers. He asked if it was a 1750, i replied "something like that".
The tacho died on the way home too.... that and the gearbox mount is on the list for the weekend. I think i will put the bumpers back on as it is booked for a RWC next week in preparation for club reg.
Anyway, back to the 75.
The thermostat hasnt been doing its job. The indicated coolant temperature goes up and down with ambient (for a given motor load). For instance, yesterday morning the indicated temp was about 40 degrees, ambient was about 5. Yesterday afternoon, indicated temp was about 50 degrees, ambient about 15. Radiator is working :) Thermostat is not :(
So I removed the thermostat and dunked it in a pot of boiling water. It opened. Took it out. It closed, but not quite. The valve was not closing square to the alloy body. By pushing on the guts of the thermostat from the side (through the port that connects to the cylinder head) i was able to square up the valve to the seat and get a much better seal. I cycled it a few times in the hot water and it sealed up well each time so its back on the car. Lets see how long it works for.... could be a cheap fix, could be a waste of time and coolant.
Quote from: Divano Veloce on July 03, 2014, 07:24:22 PM
On the way home today i swung into Parker St to see if a 75 was outside TKL. It wasnt...
Nope, we now have a car park in near the pattern shop, where all the scrap steel etc. used to go for the moulding shop.
Ahh, sneaky! Next time im coming through Castlemaine I'll drop by.
The thermostat repair worked! Temperature quickly rose to just a whisker above 80 and stayed there all the way to work (~75kms). Lets see how long for....
A notch over 80 is where mine sits regardless of the day or weather. So stable it's almost worrying in the Alfa ;D
Regarding the parts you are after
RHS headlight (no rust) - Is yours rusted? The main bucket deflector or the L shaped bit that just fills the space across the bottom and up one side?
My 3lt had rusted the L shape bit. The headlight pulls apart easily [Lense is only glued in place, lever it gently with a heat gun. Use a plastic spatula], then send it off for re chroming.
Power steering idler pulley - Have a look at it, could we machine it out to press fit a standard bearing? I'm sure I could knock something up for you...
I replaced my Tstat with a new one from Alfa Service in Germany. Not too badly priced. Like you, mine wouldn't return to fully closed but cleaning it thoroughly didn't work either.
With PS pulley; is it just dry? If so, try soaking it in a bath of engine oil. I have found that can help it for a while. Of course that won't help if the bearing is actually worn.
I just replaced a water pump on a range rover whose bearings were so bad the pulley had almost 2cm free play!
With the vibrations, a few ideas to check. First, make sure the main rubbers are ok (three engine mounts, three transaxle mounts). Next, check the centre prop shaft bearing. Then the gap between the rear engine housing and prop shaft (should be 7mm). Don't forget to check the snubber while you are there. Look at the three donuts while turning the prop shaft and check for condition. Finally, an uneven running engine can also create vibrations so make sure that is not the cause.
About HT leads.
The original TS high tension RF suppression goes about it in a different way to most other local makes. It does so by introducing a 5K ohm resistor into the plug connector. The HT leads are made of a multi strand stainless steel wire and should have virtually no resistance.
The reason behind this is a constant resistance presented to the HT coil irrespective of the length of the individual lead. This is very important because most other systems use an RF suppressor resistance in the lead and not the plug connector thereby causing less resistance in short leads and more resistance in long leads.
In turn this causes different HT voltages to be applied to the spark plugs depending on the length of their individual leads.
The original TS system is particularly good as the leads themselves last forever as there is no carbon conductor in them like resistive leads to fracture. They are bullet proof.
Finally a 5k ohm RF suppression is adequate for most ECU protection. The less you use, the greater the risk of ECU malfunction due to spurious signal noise interference. Too much resistance simply diminishes the quality of the HT for no gain whatsoever.
So the advice here is if you have a good set of TS original spark plug leads, hang onto them tighter than your wallet in a Moroccan alleyway.
Thanks Guys,
I did the loosen and rev trick. The gearbox crossmember moved a bit and the vibration has changed somewhat but is still there. Am i right in thinking that an out of balance vibration would increase with rpm but an alignment issue with the donuts would reduce with rpm? Mine is bad up to ~2500 RPM but almost gone at 3000+.
The HT lead info is gold! So the resistors in the plug caps on my leads are mostly shot.... I will investigate a method to repair the plug caps as like you said MD the rest of the leads are fine. I will post any success/failure i have here....
(http://i90.photobucket.com/albums/k248/ohospaghettio/F048ADB3-BDAB-4E37-BA77-A5B70C3F9E49-862-000002989C64BEE7_zps71247ee9.jpg)[/URL]
Resistor burnt out... These are not repairable as the terminals are crimped onto the ends of the resistor then cast into the bakelite
Car almost passed rwc, needs rear discs. While I'm replacing them I'll do the drive shaft seals.
Anyone know where I could get a pair of drive shaft seals and rear discs locally?
The pads and discs came out easily. It seems that the adjusters work!
So I've ordered discs... RDA667 apparently suit 88-92 v6 an TS
I'll also replace the pads while im at it, they're over half gone... Any advice on brand/source for these?
(tiny rear brakes for a 50/50 car...)
I'm going to replace the axle seals while i have the discs off. The manual describes the proces well (press apart, press/press with heat together...) but it'd be great to have the seals on hand to install. Any idea on the dimensions/part No. of these?
Make sure the discs are for the 75 Twin Spark.
There are a lot of online sellers out there that just copy info out of catalog which are wrong to begin with.
There are a lot of local suppliers you can try, check the front page of the Club website.
When I changed over my 3lt and TS I noticed only one difference between the 2.
The V6 uses m10x1 bolts for the drive shafts going through the discs where the TS uses m8x1.
The clearance holes for the TS discs are smaller, probably 9mm or 8.5mm. The 3lt would be 10.5mm or 11mm.
Would it matter if you used V6 discs? Probably not, unless you don't tighten them up properly.
The discs arrived and look to be correct!
It seems that no-one that sells brake pads think that they sell pads for the 75 however i am fairly certain that they're the same as 1750/2000 rear pads, same as alfetta pads....... these are readily available.
I havent had much time to work on the 75 (4 weeks in Saudi didnt help much)...
anyway, i have removed the transaxle and replaced the following:
drive shaft seals
discs
pads
de-dion bush
watts bushes
transmission mounts
engine mounts
The drive shaft seals were straightforward but tedious to replace. The axle must be removed from the bearing/bearing flange to access the seal. It was only then that i could identify the seal and source a replacement (the're 36x56x9 i used 36x56x10). Here they are coming apart with a hydraulic puller:
(http://i90.photobucket.com/albums/k248/ohospaghettio/23430A0D-D9B4-455D-84D9-1102B2B0629D-1824-0000010B760C164E_zps4c36a999.jpg)
(http://i90.photobucket.com/albums/k248/ohospaghettio/AFFE2893-5540-4F3D-8189-4CD77F9DB3EB-1824-0000010B8EF2E516_zpsfb4d7065.jpg)
As the old discs and pads were a bit thin i was reluctant to just retract the pistons and install the new discs and pads. Instead I removed the pistons and cleaned all the crud off them and reassembled with PBR rubber grease on the seal and high temp silicon grease on the outside of the seal between the piston and bore (under the dust seal). THis should prevent any corrosion or binding in the future and also wont melt and leak out onto the pads or discs. I just hope the adjuster seals don't leak!!
i have a good second hand tailshaft with very good guibos and center support so hopefully that will sort out the driveline vibration.
Dirty tranny:
(http://i90.photobucket.com/albums/k248/ohospaghettio/930587D7-74EA-4A89-8E77-71A847EC84F1-1824-0000010AFC766AFF_zps40588658.jpg)
Divano,
(Referring to your seal replacement photos.)
During the process of pressing out the bearing so as to get access to the seal,there is a possibility that damage is sustained by the bearing**. It is therefore good practices to replace the bearing and the seal at the same time otherwise it may not be too long down the track that the box develops bearing noises you will not be happy to hear.
** This is because pressure is exerted onto the housing.
Thanks MD,
yes, the force applied to remove the bearing from the axle is via the balls and race whereas to assemble the force is applied directly to the inner race. However the bearing itself was a gentle transition fit; it did not take much to push the axle out. The retaining nut on the other hand.... it required heat and force to remove.
If the bearings wernt so expensive i would have replaced them... But i have replaced enough parts that were in pretty good shape so far on this car...
Davino,
I am making these contributions initially as they relate to you but also with a view that others that are thinking of doing this job and follow this thread should get useful advice that is sound. I hope you are OK with that?
You got lucky with the bearing removal. It is not always the case. Sometimes they are bound up tight on the axle in which case there is a likelyhood of damaging them upon removal.
If you buy the parts from CBC they are cheap. Here are the two part numbers required.
Bearing-"SNR" 6006LLUC3
Lock ring"KOYO" CO6RING
The best seals for this application should be made from "Viton". They are brown in colour.
Incidentally, to remove the lock ring it is usually done with good cold chisel and anvil. The ring is cut almost through which reduces its tension and it is pressed off without heat. This requires a new lock ring which should be done as opposed to re-using the original one in any case.
The fitting of the new lock ring is usually heated and once this is done it slips on easily and just pressed fully home. ( sort of the reverse of your procedure).
If you have the transmission out as I see that you do, given the age of it and once again a minimum cost against the nuisance of oil leaks, the front seals on the box should also be replaced at this time.
When you say you have changed the transmission mounts, I take it that this included the rear suspension mounts as well?
I do sympathise with the cost blowouts. These projects always, always wind up costing more that one initially expects. We all fall victims to the "oh, while you are there.." syndrome and cringe at the bank statement later. ;D ;D
Very happy with sound advice. And that's great info on the bearings and retainers!
I did ask for some info before I did this work and got no response...... fortunately the process is well described in the workshop manual.
If you use a cold chisel to remove the retaining nut i can understand why you'd replace the bearing; there is no way to know if you've done damage to the bearing. Its a slow and brutal approach when compared to using a bearing separator, press and heat. It also sacrifices a reuseable part.
Although brinelling is unlikely when pressing off a transition fit, replacing the bearings is ok advice but why replace the retainers if removed as i did?
Divano,
Mate let's not make a Ben-Hur novel out of this small job. I have provided you with the basis of accepted workshop practices in the service of these components. Feel free to use the advice or modify it according to your beliefs. However let's be clear on this. If you believe that using a cold chisel will damage the bearing then simply you do not know how to use a cold chisel in this application. Your assumption is completely wrong.
Finally ( from my viewpoint) fitting a new retaining ring maintains the security tension on the output shaft bearing assembly as originally prescribed. Pure and simple.
MD I don't know you, but you seem like a well intended guy. Maybe don't get upset if your authority on a subject is questioned. To be honest I would not follow any of your advice if I was to do his particular task again but that does not mean your input is not welcome.
Finally got the car back together and running. An unexpected challenge was finding the ignition key. The car came with only one, and a pair of keys to suit the petrol cap (which i could find..). So instead of finding the single ignition key i pulled the ignition barrel out and shifted some tumblers about so that the petrol cap keys now suit the ignition. Win win!
It was a massive relief that the vibration was gone, the car feels much better to drive, the motor has loads of torque and revs really nicely. For a 25 year old sedan with an old 8v motor its surprisingly quick. I just need to re-adjust and re-bleed the rear calipers until i have a decent pedal. So its time for the Berlina to go up on blocks.....
Really glad to hear you are enjoying the 75 and that everything is running well. They are a great car, even by todays standards. It's surprisingly quick and yet still quite frugal. I'm enjoying driving mine again although I do miss the GTV!
A few suggestions for extra jobs to do that help considerably. Run a bigger gauge wire from the starter to the RHS terminal block and install a starter relay. Also, install two new relays for the headlights/highbeams as the original wiring was insufficient for 25 years of ageing.
Finally, when you need to re-gas your A/C I have had excellent results using hydrocarbons (Hychill HC12) and it's cheaper than R134A. It also lasts longer as the pores are similar to R12, unlike R134A which leaks through pores in the hoses unless they have been all changed which from memory yours haven't been.
Hychill HC12.
A good refrigerant it is. A safe refrigerant it isn't.
It is a highly flammable gas. If your air con.system leaks in your cabin and you operate an unprotected ignition source, you could well blow yourself up. This stuff should be banned for automotive application.
Do yourself a favour and read the MSDS on this substance and then make your own mind up.
Apology for contradiction GTVeloce but in the interest of safety, I felt obligated to do this.
http://archive.hychill.com.au/tech/hr600ams.htm (http://archive.hychill.com.au/tech/hr600ams.htm)
Took the car for a big run last night and tried the A/C and the air was cool, but so was the outside air.... Its been regassed many times indicated by the stickers on the radiator panel.
I replaced the cable from the starter to the terminal that supplies the fuesbox, thermo fan etc. early in the piece and would say that this is a mandatory fix for all RHD cars
It seems lacking a bit down low, it doesnt seem to have anywhere near the torque of the Berlina (but right now the Berlina wont rev past ~4500 instead starts pinging like mad). So two motors that should be pretty similar feel very different to drive.... one is a tractor, the other a toyota (no torque but power in the revs)
Another very annoying feature of both cars is the petrol fumes in the cabin, especially with windows down..... I will add the vapor circuit to the berlina to hopefully scavenge the vapor but have no idea whats going on with the 75!
Thanks for the link to the MSDS MD. Looks like its got an odourant in it so one should be able to detect a leak. In my car at the moment iIm more concerned about the petrol vapor!
Yes, in theory, HC12 is flammable. However, in reality, there is relatively a small amount of gas in our systems (a standard 75 takes 270g) and the likelihood of it leaking into the cabin in sufficient quantities for ignition whilst not noticing it is small, I believe.
As to the petrol fumes - there are a few places to start. First, check the inlet pipe to the tank for any cracks. Next, follow the hose from the tank to the separator and one-way valve which are attached to the boot wall. Just pull back the carpet and you will see them. Blow into the valve to make sure it is working. After that, it is just a single hard plastic pipe that goes all the way to the engine bay through the cabin. I suspect if you had a problem after that point you wouldn't notice the smell although, maybe the charcoal canister purge valve is not working and gas is building up in the system and somehow coming back.
I had fuel smell sometimes in the GTV until I finally got the canister and purge valve installed, even though I had rebuilt the rest of the system (in the boot etc) so it could still be the problem but I would start at the back first.
I've used the HC12 before and got the lectures about how I would die if I used it. It does have an odour and a UV dye in the one I used (gas the system ourselves as we have the equipment). Worked great. Had no issues. Still living.
Vibration is back!
After removing the GG pins from the old mounts i decided to install a new set i had already purchased... this brought back the vibration. I had a look at the "snubber" which prevents the front end of the tranny hitting the body under hard acceleration and it looked like it was adjusted too low, as in it was touching the clutch housing.... SO i lowered the front end of the transaxle enough to get in there with a spanner and adjusted it up a bit but... it still vibrates!
So with crappy old mounts its ok (probably not great but better than all other instances) but in all other cases its the same or worse than it was when i purchased the car.
So far I have replaced the tailshaft with a second hand one with very good guibos and center bearing support and I have replaced the gearbox mounts.
I am starting to suspect the clutch may be out of balance.... is this likely? the vibration is bad between 1500 and 3500 rpm but is undetectable at high rpm.
Maybe start at the front and work back. Are the main engine mounts ok? The rear engine mount? I pack these up with cut pieces of rad hose and silicon. It helps keep the alignment. Between the propellor shaft and the engine flywheel housing at the back there should be a 7mm gap.
Assuming the shaft is actually ok, then yes, it could be in the clutch. Probably more likely in the clutch housing than the actual clutch. There are two (maybe three - I can't remember) bearings in the clutch housing that can affect alignment. Does the car make a different noise at idle when you release the clutch in neutral? Does it vibrate at idle?
The fact it didn't vibrate with the old, non pinned gearbox mounts but does with the new ones kind of makes me think it is alignment rather than balance as the new mounts would change the alignment or maybe it's just the old ones absorbed some of the vibrations!
Thanks Julian for putting some thought into this....
I am thinking its something other than balance, well i really doubt its the prop shaft as I've changed it out entirely.
I have a set of new engine mounts that i will install this weekend. I'll also do a couple of things suggested on alfabb including:
loosen all guibo bolts a bit and start motor and let it run for 30 seconds then stop it and retighten
check axial load (tension) on tailshaft/guibos and add spacers as required
Rotate tailshaft 120 degress relative to clutch input at rear guibo
set bellhousing to tailshaft vertical clearance
try not to get mad and break stuff
If none of that works the old mounts are going back in
Last couple of evenings i managed to replace the front motor mounts and set the clearance between the prop shaft and bellhousing (above the rear mount) without getting mad and breaking stuff.
I loosened the rear guibo to clutch shaft bolts to see if there was an axial load on the shaft. There was a gap, but the gap was only on the lower most yoke and would close up when the tailshaft was rotated (so that the lower yoke always had the gap). This suggested to me that the front of the gearbox was too low. So i added some spacers between the gearbox mounts and the rear crossmember. This removed almost all of the gap and made all three gaps equal. Seemed like a good thing but....
the vibration is still the same, maybe a bit worse......
Another thing i noticed with the rear guibo to clutch shaft bolts loose there was a bit of play in the center aligning bush, about 1mm radial play..... does this mean a new clutch input shaft???
Any suggestions very welcome....
In both the rear aligning bushes I recently changed there was a few hundreds clearance... I never measured, just going by feel. There was no way near 1mm play in mine...
Time to measure stuff I'd say...
If the clutch shaft is buggered it could be machined down, shrink fit a sleeve and machine that to size to fix it up [machine between centres since it has a centre in each end].
Maybe a cheap/poor quality guibo? Maybe it was fitted without grease and has flogged the bushing out over time? I don't remember if you put a new one in or not...
I can measure the guibo on the tailshaft that came out of the car... also im getting pretty good at dropping the exhaust center section and the front of the tranny, should not take long to get and ID and OD of the bits
as for lube, it looks like someone used copper anti-seize to lubricate the bushes throughout the old tailshaft
You mentioned you thought the clutch was sitting slightly low compared to the prop shaft when the nuts were removed, have you checked the rear tranny mount bushing while it is under load? I'm guessing you already have but just checking...
So far I've installed new motor and transaxle mounts but the tailshaft has been replaced with a good second hand item complete with good second hand guibos and center support.
I think it has gotten better, although there is still a vibration, it feels much more responsive throughout the rev range, as though less power is being lost in transmission.
next i will measure the bush id/od at the clutch input and also do the loosen the engine mounts and center support and give it a rev. I saw on a alfabb thread that JimK used a pair of lasers (one on motor pointing back, one on tranny pointing forwards and the whole arrangement was horribly aligned... I might see what mine is like using something a bit simpler/agricultural.
fixed petrol vapor leak... it was the filler pipe split along the seam. Smeared the seam with a soldering iron to seal it up!
I think i know what the source/cause of the vibration is....
very bad alignment of prop shaft at tranny over an extended period has worn the clutch input shaft where it fits into the rear donut. With a new(ish) donut and tranny/propshaft alignment correct the rear donut is not centered on the clutch input shaft.
In pursuit of prop shaft vibrations i have sofar done the following:
Replaced tailshaft complete with good second hand unit.
replaced all motor and transaxle mounts
Adjusted rear motor mount to achieve 7mm clearance between bellhousing and tailshaft
checked propshaft alignment at clutch by loosening guibo bolts and observing clearance at yoke to guibo, gap was always biggest at the bottom (when shaft is rotated). Added spacers under tranny mounts and achieved good alignment.
After all of this the vibration has been altered and improved but is still there enough to be annoying.... I also noticed that there was a large amount of radial play at the rear guibo with the yoke bolts loose...
So I have finally measured the radial clearance between the clutch input shaft and the spigot in the rear guibo.... its about 0.4mm. So the rear end of the prop shaft could have up to 0.2mm of runout when assembled. Is this a likely cause of vibration?
i measure the clutch shaft where it is centered in the rear guibo to be 18.92mm. It looks a little worn and the chamfer is rounded...
Also the front clutch shaft bearing is stuffed.
My plan is to replace the clutch bearings and either replace or sleeve the clutch shaft. If anyone access to a rear guibo and tranny can they measure their clutch shaft so i can determine if mine is worn undersize?
cheers
Quote from: Divano Veloce on March 01, 2015, 12:04:38 PM
Can anyone measure their clutch shaft so i can determine if mine is worn undersize?
Snicker. ::)
Quote from: Evan Bottcher on March 01, 2015, 01:50:52 PM
Quote from: Divano Veloce on March 01, 2015, 12:04:38 PM
Can anyone measure their clutch shaft so i can determine if mine is worn undersize?
Snicker. ::)
;D
Do you get a noise from that region with the car in neutral, idling and with the foot off the clutch? I used to until I replaced the clutch housing bearings.
Thanks Evan for your contribution ;)
the small bearing floats axially in the housing so doesn't take any load from clutch disengagement. Its the one that's a bit (quite) loose. Yes Evan, its loose.
Underwhelmed with the response to my request for assistance (what? no-one has a guibo or transaxle in the shed and a vernier?) I bought another complete 75 with the intention of wrecking it and taking the measurements. Extreme perhaps but i was upset with all of you (except Julian).
Its body is straight but super rough, is every shade of Alfa red and the clear coat is peeling on most panels.
Mechanically it had some issues - leaking water pump, driveline vibration (of course), rear brake discs worn undersize, loose front wheel bearing, no power steering belt or tensioner pulley, gutless below 5000 rpm.
Electrically.... had a wire running from the battery to a switch in the cabin and down to the fuel pumps.... no fuse! Rear windows don't work.
THe good points, LSD and synchros seem great, awesome above 5000rpm, interior is mint, arc seems to behave, brakes are good.
So once home i got out the motronic schematic, multimeter and some alligator leads to do some fault finding of the fuel pump and vvt. For circuit continuity tests i disconnect the ecu from the loom to ensure that i don't fry anything (autoranging DMM)
The fuel pump issue was an easy fix, the wire from the fuel pump relay had become disconnected from the back of the fusebox.
I then earthed one terminal of the vvt solenoid and applied 12v to the other (with the motor running). If the VVT solenoid and variator are working the idle should get really rough or even stall... nothing happened. So i whipped the cam cover off and energised the solenoid and apart from a very quiet click there was nothing, no actuation of the variator. I pulled the solenoid apart to find its cock is worn into more of a choad, and it was installed the wrong way around.
I swapped a vvt solenoid from the champagne car and tested at idle then test drove. This confirmed what i had suspected about my other 2 twin spark cars (one has grunt but no top end the other great top end but nothing down low). This car now has both torque and power and 448000kms on the clock, brilliant! Now i just need to sort out the other two "good" cars!
In the meantime i have decided not to wreck it. It will get club reg when it turns 25 in a couple of weeks. I will spend the absolute minimum to keep it roadworthy and reliable (kind of SBR philosophy). So what i need are the following: second hand 2000 or TS water pump, VVT solenoid (or else i will have a new cock made for it), new rear discs.
If i cant get the Berlina top end power sorted there's no point taking it to Sandown again, or Phillip Island or anywhere else really. So instead I might take this car. Its completely standard so complies with comp regs for standard class. If i remove the air conditioning components and power steering pump would the car still comply? I'd like to install the biggest standard equipment bars available too, I believe they are from a Potenziata? Torsion and sway. This should make for a quick, low cost and fun track/autocross experience!
Exactly which part do you want measured? I have a clutch sitting at home I can measure (although it is old and I don't remember how good it is) but there is a dirty big yoke on the front. Is it the bearing in front (driveshaft) or behind the yoke (clutch)?
Also, you have stolen my idea for a cheap race car! Beef up the suspension if you like but a bigger priority would be decent pads and fluid for the brakes and possibly some ducting onto the front callipers. Allows you to keep going hard all day and not retire early with no brakes...
I finally got some time to work on cars today.... progress has been glacial.
But the Berlina has only a couple of weeks of permit days left.... So its time to get another car on club plates.
I reinstalled the clutch with new bearings in the champagne car today, got clutch bled and gear linkages working ok. Tomorrow its cam cover and VVT, plug leads and test drive. I am hopeful that the clutch bearings and improved prop shaft alignment will have addressed the vibration.
I begrudgingly purchased a new water pump for the red 75, and a set of spark plug leads. Just need a VVT solenoid and i can have both cars on club reg!
Any TS big cam converters done away with their VVT?? I could put a solenoid to good use.
Champagne 75 passed RWC and will be on club plates when it turns 25! Some other good news is that the persistent vibration is improved (but still there)... centering of the rear guibo on the clutch input shaft i think is the key... Motor still seems a bit sluggish down low but sensational above 4500-5000 rpm.
When i get time I'll swap all the nice parts off the Red car onto the champagne car. Then get RWC on red and club plates....
The red car is such a great candidate for a club car... i cant wait to get it on the road!