33 Tappet shims

Started by colcol, January 06, 2011, 11:31:27 AM

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colcol

This is a odd subject, but on Alfa 33's 84-88, they had mechanical tappets, and the clearances were set by changing shims on the top of the tappet bucket, i have always found these shims hard to get from Alfa spare parts places, but they are EXACTLY the same as the ones used in the 70"s VW golfs and passats and the VW specialists always seem to have a good supply of them, if anyone has any tips on changing them or know of special tools for changing them, please let us know, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

Frank Musco

Hello Colin, here is a link showing two pictures of the tool.
http://www.alfabb.com/bb/forums/boxer-engined-alfa-romeos/42137-removing-valve-shims-car.html
I don't know where to get one locally, I made a tool from a screwdriver which does the job.

Tips for changing shims:

Clean around spark plugs and remove to make it easier to rotate motor and check piston is away from TDC.
Remove oil from camboxes with a syringe to avoid oil squirting and easier to see shim and cam position.
Position camshaft so both lobes are away from buckets for particular cylinder, also check position of piston is away from TDC so you can't hit it with a valve when depressing valve bucket.
Check the tool is fitting on the shoulder of the bucket you're changing shim, and just missing the shim your changing and the adjacent bucket. This is where the tool slips and you get oil squirting back at you.
Use a strong small, thin, flat screwdriver or pick to dislodge the shim from the bucket. Sometimes the shim doesn't want to come out because oil suction and tight fit.
Then I use a magnetic aerial type tool to get the shim out, or you can use some pointy nose pliers.
I made my tool quickly so it doesn't hold the valve bucket down on it's own as the proper tool does, I have to hold it with one hand while using the other to QUICKLY remove the shim, which can be difficult.
Job done.

My shim tool is 6.5mm wide with 1.5mm square step each side.


colcol

Re tappet tools, Stahlwille, German tool manufacturer make a tappet bucket depressing tool that is used on Fiat x19's, the part no is '12962', it seems to be listed on various tool  suppliers oversea's, but you will have to modify it as it won't fit in the valley of a 33\Sud cam housing as the handle is too large, you can modify it by drilling out the 2 rivets that hold the handle on the tool, and then put a bolt in the handle so as you push and depress the bucket you can rotate the handle out of the way of the housing, and you may have to file the profile on the tool so that it clears all the obstacles Alfa put in our way!, if you have a look at the tool, it will all make sense, if i ever work out how to put pictures on the interweb thingy, i will post mine, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

Ray Pignataro

Frank ,Colin this may be a little off topic but has any one yet worked out how to convert 1.7 quad cam from tappets to shims but not at the ridiculous o/s prices

Evan Bottcher

Continuing off-topic.  I've been told that mechanical lifters to fit a Renault Clio 16v will fit the 33 16v, with the right size stem inside to fit shims under the bucket.  Of course you'll have to drop the engine to do the clearances, but on a race engine that should be okay?

These are the lifters:
http://www.arrowprecision.co.uk/details.php?id=66714
They were 10 quid cheaper when I bought a set, but the dollar wasn't nearly as strong *sigh*  Lost out on that deal.

Attached is a photo of the lifters, have had them for a year but haven't trial fitted them so can't guarantee they are right.  Got all the bits sitting there to build the engine now, just other projects keep getting in the way...

Oh - and how do I now that these lifters will fit?  A guy from the Internet told me.  What could go wrong?
Newest to oldest:
'13 Alfa Mito QV
'77 Alfasud Ti
'74 Alfasud Sedan
'68 1750 GTV
--> Slow and Fun - my Alfa journal

Frank Musco

Ray, Not yet mate. Also wondering what the effect of going from hydraulic to solid will be on the standard camshafts?  Hydraulic buckets are always in contact with the camshaft, and solid buckets have clearance, So, is this a problem??  You know I don't want to change 4 cams. Has anyone used the standard cams with solid buckets, and if so, what valve clearance was used?

Evan, I have been told that the Clio 16V lifters do fit, but haven't bought a set yet...one day...

Evan Bottcher

I've also heard people say not to bother, just chuck the motor in and drive it - that the hydraulic tappets are fine to 7000rpm with the standard cams.  Only need mechanical with big race cams or big revs...
Newest to oldest:
'13 Alfa Mito QV
'77 Alfasud Ti
'74 Alfasud Sedan
'68 1750 GTV
--> Slow and Fun - my Alfa journal

pep105

Frank do the 4AGE lifters fit in the 33 16V as well ? I remember you were going to try them
Current
'74 GT 1600 Junior  (Currently under restoration)
'84 Alfetta GCL Sedan
'02 Vespa ET4 150
'05 GT 3.2
Past
'82 Fiat 131 Superbrava Mk II
'82 Alfetta GTV 2.0
'88 75 Twinspark
'80 Alfetta Sedan
'02 147 Twinspark

Ray Pignataro

Evan what you dont realise is 7000 revs is Franks off idle before he goes to mid range or full throttle

Ray Pignataro

Frank i dont think it would matter to the cam it is the same cam in 1.7 eight valvemotors irrespective whether the lifters are hydraulic or mechanical

colcol

About 20 years ago i was involved with camshafts in my work, this is what they taught me, there are 3 types of grind for O.H.C. camshafts, [1]O.H.C. for cams with rockers, [2] O.H.C. for cams with hydraulic lifters, [3] O.H.C. for cams with solid lifters [shims], with hydraulic lifters there is a slight ramp on the cam to 'pump up' the hydraulic lifters to keep zero lash on the camshaft, on solid lifters, there is no need for a slight ramp because the lifters are solid and don't need to be 'pumped up', one thing i learnt was don't mix up the cam profiles as they won't work properly, ie hydraulic on solid or solid on hydraulic, make sure the cam is dead straight within ,01 mm otherwise the hydraulic lifters won't work [seriously], if a cam came back with the complaint of a rough idle, then it was most likely the owner had dropped it and bent it, without letting on, i would straighten it and the owner would be on their way and later on they would phone and say it was all good!, i used to think that hydraulic lifters were for slow revving bread and butter motors until i learnt that in  those days of Group A Touring cars, when camshafts were unlimited in their profiles, the V-8 Holden and Ford Sierra's, would change camshafts at race meetings to search for that extra power, but would be running HYDRAULIC lifters because they worked ok and that when the new cam was put in there would be no need to set any valve clearances!, and this was in the days of being no rev limits on the engines, but the hydraulic lifters must be in good condition otherwise they won't work properly, through this period i grew to despise pushrod motors and luv O.H.C. motors like what ALFA has been building for about 100 years, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

Ray Pignataro

Colin I stand corrected, very insightful post thank you. I gues it would be cheaper to replace lifters AND cams thendo the conversion from hydraulic to mech and still have to do cams

Frank Musco

Quote from: pep105 on January 11, 2011, 11:01:54 PM
Frank do the 4AGE lifters fit in the 33 16V as well ? I remember you were going to try them

Pep, the 4AGE lifters are 31mm diameter and 33 16V are 33mm. Before measuring the 4AGE lifter I thought they were going to fit, very close though, and would need work done to the cylinder head like welding up or sleeving to make them fit. I like that type because you can adjust the clearances without removing the cam. When I get the chance I will chase up some Clio 16V lifters.


Colin, thanks for the info about cams. Very interesting. O.H.C, the only way to go.
Also very interesting about the Grp A Touring cars using hydraulic lifters. Do you know if they restricted the oil pressure to the lifters relative to what the crank journal oil pressure was? So for example, if the crank saw 100 psi, the lifters oil pressure would be 50 psi?
I wouldn't mind using the hydraulic lifters, but I don't know how they exactly work and how oil pressure changes effect the lifters operation.
I ask because I have modified the oil pump in the race car, 1500 8V solid lifter, to give over 100psi at high revs and about 50psi at idle when hot, and when I modified my brothers oil pump in his 1700 8V hydraulic lifter engine to the same spec as mine, the engine started fine but almost immediately afterwards began to play-up, sort of backfiring and would not idle or want to rev properly, it seemed to be  keeping the valves open or...? Quickly returned pump to original factory spec and motor ran perfect again, magic. Also noticed that on the track my brothers car will scream to 6500 rpm and then hit a 'wall', no valve bounce or weird noises, checked heaps of stuff, including valve springs, and I think the hydraulic lifters are to blame? Could they be at fault?

colcol

Re Hydraulic lifters, i know that some engine reconditioners can test hydraulic lifters but sometimes the cost of checking them is almost the same cost of new ones, that is with Holden and Ford things, with Alfa hydraulic lifters i would say they would be a bit more expensive, so they would be worth checking, the symptoms of rough idle suggests that there is too much oil pressure and the valves are not closing causing lack of compression, the 'hitting a wall' at 6500 rpm could be caused by the hydraulic lifters not opening the valves enough and the engine just running out of air, the Group A engines were all dry sumped and therefor didn't suffer from the oil surge and pumping air that our more standard engines suffered from, problems with hydraulic lifters were well there were no problems as long as they were replaced on a regular time frame, Colin.
1974 VW Passat [ist car] 1984 Alfa 33TI [daily driver] 2002 Alfa 156 JTS [daily driver]

Frank Musco

Thanks Colin. Sounds good to me. I did not have the lifters checked. I think of a failed lifter as one that causes valve noise at idle, then goes away as the engine gets off idle and then begins to tap again at high revs, more than 5000rpm. This was not happening with my brothers car so I thought the lifters are OK.

My efforts for chasing revs is often confusing and I find myself going backwards more often than making an improvement. Re lifters at high revs, I thought that they were 'pumping up' therefore keeping the valves open for too long, and importantly the inlet valves closing too late, causing the engine to have the inability to compress the mixture, and no more torque. Could this be happening?