Project car - 1989 75 3.0 V6 [Updated 12 November 2021]

Started by shiny_car, July 05, 2011, 09:38:53 PM

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shiny_car

Hey ALFA750.

Unfortunately, I can't comment on mine yet. It wasn't working when I bought the car, and haven't had it running since. I found an incorrect relay fitted for the compressor clutch, so I'm hoping that is all that was wrong.

However, one upgrade I plan is to replace the original serpentine condenser for a more modern parallel flow version. This is meant to improve the efficiency of any old AC setup. The refrigerant choice also has an impact, so you could talk to a local specialist about what choice is available.

:)
Giulietta QV TCT . 1.75 TBi . Magnesio Grey - Black
GT . 3.2 V6 . Q2 . Kyalami Black - Red
75 . 3.0 V6 . Alfa Red - Grey

ALF750

I hadn't heard about the condenser change.   Finding seals for the compressor was the problem.  thanks.

shiny_car

#272
Not a big update this month. Though cleaning under the car was time consuming, and seems there's not a lot to show for it. :P

I resprayed the prop shaft halves gloss black. It will be some time before reassembly; I need to source parts (flex joints, etc) when funds permit.



Spent several hours under the car scrubbing the centre tunnel clean, and masking, in preparation for painting.





Also removed the left sideskirt, to facilitate painting the chassis to the very edge.





Then painted with black 3M Body Deadener. A couple small patches, either side close to the red crossmember, are pieces of sheet metal that will be painted red. So next month, I will complete the red areas, and touch up any spots missed with body deadener, and remove the masking.



Next: to remove the gearstick assembly, first the gear knob was removed. Simply pulls off.





Gearstick assembly detached from underneath by unbolting from the chassis.



After removing an internal circlip, the pieces were disassembled.



New parts to be fitted are a replacement rubber boot, a plastic spacer (though original seems in good condition), and metal bush. The latter usually wears and contributes towards a sloppy linkage; I believe these are NLA, but I found a new one on eBay.





The gearstick was cleaned, and its plastic seat separated from the bearing. The seat has some wear and a crack, but still functions properly. I have not found a new replacement. The original metal bush is press-fitted into the end of the gearstick. O-rings fit either side, into recesses, and the spiral groove presumably retains grease. Though, I can't rotate the bush within the gearstick by hand, so it either isn't designed to rotate or the existing one is stuck.







That's the brief update for this month. Thanks.

:)
Giulietta QV TCT . 1.75 TBi . Magnesio Grey - Black
GT . 3.2 V6 . Q2 . Kyalami Black - Red
75 . 3.0 V6 . Alfa Red - Grey

VeeSix

Lord of the serpent, what happened to that wheel?   :o
1985 Alfa Romeo GTV6 V6 2.5 12V 
1986 Alfa Romeo 90 V6 2.5 12V
1990 Alfa Romeo 75 V6 3.0 12V Potenziata
1990 Alfa Romeo 164 V6 3.0 12V Zender
1991 Alfa Romeo 164 V6 3.0 12V QV
1992 Alfa Romeo 164 V6 3.0 12V QV

shiny_car

Oh, just a minor tussle with a wheel nut.  :P >:( Refer to the 11 January update.  ;D
Giulietta QV TCT . 1.75 TBi . Magnesio Grey - Black
GT . 3.2 V6 . Q2 . Kyalami Black - Red
75 . 3.0 V6 . Alfa Red - Grey

Cool Jesus

Hey Shiny, considering the transaxle propshaft setup is virtually unchanged throughout the varying models with this. How did you go with the rubber grommets and bushes at the various ends off the two shafts? I've had no luck as yet locating replacement items. Items are those circled red in photos. Mine were either missing entirely and all sealing grommets are worn if not torn.

PS. I think I read a short discussion on here about whthere or not the shaft bolts mattered if they went into the same spot. I can confirm that it does matter. To what degree ??? , but I have an '89 Alfa technical bulletin which states the driveshaft is factory balanced 'on the car'. Adjustments are performed via differing thickness nuts, even installing two nuts on the one bolt. As such they advise that all mounting hardware position must be marked and refitted exactly as factory assembled to preserve balance.  (underlining per bulletin)

As you could appreciate, many an owner or (non-alfa) tradie, wouldn't have followed or known of this and the inevitable occured. Evenso, I'm sure I've read elsewhere that the two shafts should be (and can be) balanced as a single unit, along with any hardware, at any reputable drive shaft shop... I wasn't overly concerned on hardware postion with the Alfetta as I'll be ballancing per later option.
Present:
* '76 Alfetta GTAm 2.0 (project)
* '03 147 2.0 TS
*'12 159 Ti 1750 TBi
===================
Past:
* '10 159 2.2 JTS
* '89 164 3.0
* '98 Spider 2.0 TS

Al Campbell

I'm pretty sure, well a little bit sure  ::) that Benincas do prop shaft balancing - although they are in Surrey Hills, Melb. Which isn't that far from Sleepy Hollow.

shiny_car

#277
Quote from: Cool Jesus on March 18, 2014, 02:23:43 PM
Hey Shiny, considering the transaxle propshaft setup is virtually unchanged throughout the varying models with this. How did you go with the rubber grommets and bushes at the various ends off the two shafts? I've had no luck as yet locating replacement items. Items are those circled red in photos. Mine were either missing entirely and all sealing grommets are worn if not torn.

I noticed a new centre joint seal has come up on eBay from Italy. Not cheap, but if you need it...
http://www.ebay.com.au/itm/TAMPONE-ALBERO-GOMMINO-TRASMISSIONE-ALFA-SZ-RZ-75-NUOVO-ORIGINALE-60521191-/321354804862

I've not seen a spare centre bush though. Mine is still pressed into the shaft, and don't plan to change it.

The rubber seals on my front and centre joints seem in good condition, so I will reuse them.

QuotePS. I think I read a short discussion on here about whthere or not the shaft bolts mattered if they went into the same spot. I can confirm that it does matter. To what degree ??? , but I have an '89 Alfa technical bulletin which states the driveshaft is factory balanced 'on the car'. Adjustments are performed via differing thickness nuts, even installing two nuts on the one bolt. As such they advise that all mounting hardware position must be marked and refitted exactly as factory assembled to preserve balance.  (underlining per bulletin)

Good info, and interesting.

Whilst I speculated it probably wasn't necessary, I did actually mark every bolt, washer, and nut for every location, so I will be safe in this regard. It seemed a no-brainer at the time, easy enough to do. I just wasn't sure how critical it was.

Seems it must make a difference.

I did find a double-nut on one of the rear joint bolts. Factory balancing?! The nut wasn't the correct thread pitch for the bolt. Appeared an afterthought to me, but I can't see why it was there except for balancing purposes.



:)
Giulietta QV TCT . 1.75 TBi . Magnesio Grey - Black
GT . 3.2 V6 . Q2 . Kyalami Black - Red
75 . 3.0 V6 . Alfa Red - Grey

Cool Jesus

Huh, missed that second nut through your thread. There you go. If the thread is wrong, it wouldn't surprise me if a previous owner threw it on to resolve a possible vibration from the shaft. I've always wondered what and how one would balance the shaft on the car? Perhaps the town fluzy was placed in the car until her smile went away :(
Thanks for the link. Part no doesn't mesh, but it would be the same rubber grommet I need for the Alfetta. Pricing is steep, the pitfalls of restoring an old Alfa I guess. I'll have to think about it a little more and see if I can find a local substitute while they're still available.
Thinking about the bushings just reminded me that I have access to a friend with a mill, so should be able to make some new bushings there.
Your certainly doing a Stirling job on the build shiny. You had some posters also talking about the paint throwing the prop shaft out. I didn't chime in at the time as I didn't see you doing anything questionable. As you said, you had unwittingly marked all the hardware as required  ::) Yeah I've seen talk elsewhere about paint and balance, generally aslong as it's an even layer (ie sprayed or powder coated, not brushed) if there is any unbalance it will be inconsequential.
Present:
* '76 Alfetta GTAm 2.0 (project)
* '03 147 2.0 TS
*'12 159 Ti 1750 TBi
===================
Past:
* '10 159 2.2 JTS
* '89 164 3.0
* '98 Spider 2.0 TS

jazig.k

Both my 3Lt and Twinspark have the same nuts and bolts right through the tailshaft yet both alfetta GTV's, '78 and '82, have had different nut sizes.

Maybe alfa ditched that dodgy idea later on...

shiny_car

#280
This month's update completes the work performed under the chassis centre tunnel.

Firstly, I (brush) painted the remaining patches of the chassis with Alfa Rosso 130 Red,for a neat and tidy appearance. Masking tape removed, and the exterior of the rear brake and clutch hydraulic pipes were cleaned.







Back to the gearstick lever, I pressed out the bush. After a clean, indeed the bush is designed to rotate within the lever, but mine had some corrosion and lack of grease. My gear shift rod must have been loosely bolted to the bush instead of firmly clamped, so rather than the bush rotating inside the gearstick, the bolt was rotating inside the bush.





One planned small modification was creating a 'short shift' gearstick, without structural changes to parts of the car. I have encountered many, many topics on 75 and GTV6 forums about various designs, each with pros and cons.

Part of the principle simply entails lengthening the gearstick below the pivoting spherical bearing (ie: the bottom of the stick, under the car). There is apparently more gain in Alfetta's, which have a shorter lower section than 75's. Also, if you can accept having to move your hand further from the steering wheel (which 'racers' won't like!), cutting the top of the gearstick shorter will help reduce the amount of 'throw' with each gear change. I plan to do this too. In Alfetta's, some people simply cut the lower end of the gearstick, then weld in an extension. I don't have welding equipment, and can't weld.

I think you also need to be mindful of over-doing it. If the throw fore/aft, and left-right gate, is too short, you risk mis-shifting and selecting the wrong gear (eg: wrongly downshifting from 5th to 2nd instead of 4th). And there seems a distinction between 'faster' and 'shorter' shifts: the relatively fragile synchros and dog gear teeth don't seem to cope well with fast gear shifts. Regardless, my modification is unlikely to produce a large shortening. However, I haven't done the calculations, but they will be easy to do and might update this topic accordingly. And basically, even an incremental gain is better than none.

The isostatic linkages on the gearbox will also be replaced and overhauled at a later date, to remove any slop and improve the feel.

Firstly, I temporarily reassembled the gearstick assembly into the car, and shift rod. The main limiting factor with extending the lower end is striking the chassis centre crossmember. I measured the clearance to be 11mm. Other obstructions in the area are an exhaust heat shield, that fits immediately below the gearstick, and the protective rubber boot which will be sandwiched between the gearstick and heat shield.



I decided to 'extend' the lower section of the gearstick by 9mm. Any more would unlikely fit without further modification, and any less would be...less! Again, without doing the measurements and calculations, this should approximate a 10% extension.

How? Well, I envisaged simply moving the spherical bearing on the gearstick 9mm upwards. Not only does this lengthen the lower section, it also shortens the upper section, both contributing to a shorter throw.

I marked the gearstick accordingly.



Unfortunately, this didn't prove to be nearly as easy as I anticipated. On inspection, the bearing is press-fitted onto the stick; but wow, how tightly?!

Attempting to apply force directly onto the bearing with my press proved fruitless. The angled design of the gearstick meant the stick merely flexed whenever the hydraulic press pushed down. I used my blowtorch to heat the bearing and all my tools in a makeshift manner, but couldn't focus the force appropriately. One attempt used a car stand at the bottom to support the end of the gearstick, then a vice gripping the middle, pressing onto the bearing via a spanner! It was stable, but the stick still flexed and slipped through the vice, instead of moving the bearing.



I nearly gave up, but had a week away from the car to think afresh. Meanwhile, I sprayed some penetrating oil onto the bearing, hoping it would loosen the fit onto the gearstick.

Realising I needed to support the stick directly below the bearing, I wanted a ring of metal in this vicinity. No welding equipment! So, visited a local welding workshop and they did the job on the spot. Removing the weld would be easy enough, with my grinder, but in retrospect, the bead doesn't obstruct the shift action within the assembly, and is hidden from view by the gaiter.



Now it worked! I threaded the stick through a ring spanner to support the welded ring of metal, in turn supported by the black hydraulic press plates. Then, a piece of 30mm wide steel box section - its internal width big enough to slide over the end of the gearstick - pushing against the adjustable spanner.





I still heated the bearing with the blowtorch, and after applying force, I heard a small 'twang' and the bearing started to slide. I pushed it to the 9mm mark, or just short, and after trial fitment in the car, the bottom of the shift rod clears the crossmember by 1-2mm. Hopefully that is enough to avoid the pieces touching during vibration.



Whilst working on the gearstick assembly, I noticed a small amount of up-down movement of the stick within the housing. This was due to a very small gap between the white bearing seat + black plastic spacer + retaining circlip. 'Small', but still annoying, and possibly contributing towards the sloppy feel in the gear shift mechanism. Therefore, I cut a thin spacer to fill the gap, using clear plastic from old packaging. This was ~0.25mm thick, and perfect to remove all the up-down movement.







Next, I started refurbishing the centre chassis crossmember. There was some surface rust, and the two original exhaust hangers had broken, replaced by only one welded hanger.



I removed the remnants of the original hangers, and the replacement one, with the angle grinder. At Bunnings, I bought some galvanised wall hooks, then bent and cut them to fashion new hangers by mating two hooks together, for strength, per side. Of course, I could have visited an exhaust shop to weld new hangers, but where's the fun in that?! They will be riveted to the crossmember, but if too weak, I will have new hangers welded.





A 'mild' flap disc was attached to the angle grinder to strip the old paint and surface rust. I also cleaned the gear shift rod, and prepared the gearstick.















The parts were sprayed with Etch Primer then Enamel Primer. After allowing to dry, they were sprayed with gloss black enamel.





Lastly, the heat shield over the exhaust catalytic converter was cleaned, with degreaser then high pressure hose, then scrubbed clean with a scourer. The gearstick sits above the shield where there is a rectangular depression on the top/convex surface.









This work largely concludes the refurbishment of the chassis tunnel area. I am yet to purchase parts to refit the prop shaft. But next, I will commence work on the interior and complete the electrics, rather than the rear suspension and transaxle. The latter requires purchase of several expensive parts (springs, shock absorbers, antiroll bar, exhaust, vented discs and caliper widening spacers, etc), and because we will be relocating to our new house and garage towards the end of the year, I need to roll the car onto a trailer, and not have the De Dion dismantled. Once in the new garage, I will have ample space and the time to purchase parts and rebuild the rear.

See you next month.

:)
Giulietta QV TCT . 1.75 TBi . Magnesio Grey - Black
GT . 3.2 V6 . Q2 . Kyalami Black - Red
75 . 3.0 V6 . Alfa Red - Grey

jazig.k

#281
Pretty sure I remember you had CSC extractors? You won't be able to fit the heat shield with the extractors... Unless to make a new one or heavily modify the original [I don't remember how much it needed changing but my heat shield hit the scrap heap]

Edit: I might be wrong actually, I know when I lengthened my shifter it rubbed the heat shield, so I modified the shield to accommodate. Later on came my CSC, maybe it was a combination of the 2 that meant I scrapped the shield...

shiny_car

Yeah, CSC will be fitted.

Good point; I haven't tried to test fit with the heatshield, and it will likely foul the rubber boot covering the bottom of the gearstick. If so, I will modify the heatshield and gamble on the exhaust being ok. It will be a while before the full exhaust is fitted, and cats added.

How much did you extend your gearstick by?

:)
Giulietta QV TCT . 1.75 TBi . Magnesio Grey - Black
GT . 3.2 V6 . Q2 . Kyalami Black - Red
75 . 3.0 V6 . Alfa Red - Grey

TimD

Quote from: jazig.k on April 09, 2014, 12:42:16 PM
Pretty sure I remember you had CSC extractors? You won't be able to fit the heat shield with the extractors... Unless to make a new one or heavily modify the original [I don't remember how much it needed changing but my heat shield hit the scrap heap]

Edit: I might be wrong actually, I know when I lengthened my shifter it rubbed the heat shield, so I modified the shield to accommodate. Later on came my CSC, maybe it was a combination of the 2 that meant I scrapped the shield...

I have CSC extractors on my car and they clear the heat shield.

jazig.k

I have seen 2 different types of shift lever... Dad's '82 GTV was the same as yours, shifted the ball joint up the shaft [his had grub screws holding it in place], but mine was a single piece so I believed. I cut and welded a piece into the lower section and modified the shaft going back to the box [along with the linkages etc at the box]. I can't run the original rubber boot. It fouled the shield but I fixed that by bashing the clearance point larger with a big hammer! I ran standard front exhaust up to the cat with no problem, when I fitted up the CSC's the shield had to go, it just didn't fit.

TimD - Did you keep the full length of the CSC including the flex pipes? It's been a few years since I fitted mine, but I have seen CSC's without flex pipes, just wondering if that's why yours fits? I should crawl under the car tonight and have a look. It's on stands at the moment.