I'm leaving for the SCCA solo national championships on Saturday, at least that's my plan. Tonight, I pulled the valve cover to have a look and found a couple of suspect retainers. They are pictured below:

Intake side on cylinder #1:


close-ups of left-hand valve:




Exhaust side, of cylinder #2:


Do any of the retainer gurus have a gut feel for if these are 'replace after nationals' or 'ticking timebomb, replace before nationals'? This is the first time I have opened up the valve cover since owning the car (just over 2 years). It sees exclusively autocross use, except for a few track days and is towed to/from events because I do not have it registered for street use. I did have a brief 2-->1 misshift in July. Unfortunately, I did not have my datalogger running during that particular run. The car has seen about 20 autocross runs of around 50 seconds each since that misshift.

I have a head that I can pull off of a spare motor and swap in, but to b honest, I'm already down to the wire on getting the car ready to leave. If it's in the 'ticking timebomb' categoy, then I'll scrap some of my to-do list or possibly leave a day later to get the swap done. So, what do you guys think?

 

4th pic looks low, but it's hard to tell in the pic. If you pull the cams it will be easier check.


I replaced all of Liquidsation's retainers after a 5-2 shift, every intake retainer was cracked.

 

The pictures look opposite of how it looks to the naked eye. The left intake valve on cylinder 1 is the lowest of them.

 

From my research, the veterens have said that if you can see the inner wall of the retainer (meaning the keepers are low enough) that it it most likely a bad retainer and could lead to a crack.

I pulled mine a couple weeks ago after a very small overrev and all of them wer the same (good). All the keepers were sunk maybe .5mm from being completely level with the top of the retainer. I used a dental pick to "feel" how low they were.

If you have some that seem lower (like the first pic), I would probably replace them. the full it is only like 115 bux anyways so its good to be safe.

Good luck, I know the feeling

 

Good on the left, bad on the right.

 

I took the liberty of adjusting the lighting & contrast a bit.
This is a cut from pic #1, intake cyl #1.
IMO this retainer has raised a bit on the valve stem.
You can see the shadow like in Billmans pic Shopman posted.
In other words: if I would find a retainer like this on my car I would be worried.

 

Thanks, Spitfire. That was my thought as well. I just wanted someone to confirm before I do the work. Now, the question is: replace the keepers and retainers with new AP2 parts I have in my parts collection, or swap a spare head in. The head only has 6000 miles on it since replacing all the retainers and keepers.

 

I'd do whichever is easiest for you to do. I don't know if he still does, but Billman used to recommend everyone change to ap2 retainers if they cracked their ap1's.

 

I decided to just replace the retainers and keepers. Leakdown with the motor cold was 10% or less across all 4. I've been at it for about 3 hours now, and have 2 cylinders done, plus the exhaust side of #3. So far, all the exhaust retainers have no problems. I dropped and lost a couple of AP2 cotters -- on the floor, not into the motor. I dropped exactly one more than the number of spares I had. So, I've been replacing all the intake side stuff and reinstalling the exhaust side. So far, the one SpitfireS enhanced was badly cracked, plus one on cylinder #2. I'll post pics when I'm done.

 

Looking forward to the pics.