We work on and see a lot of S2000s here and have changed countless retainers on the AP1 models dues to retainers scares. I would say 90% of the ones we have changed show no signs of issues and still look brand new, but it's piece of mind.

Here's the signs to look for :

Pull the valve cover, you should see the tip of the valve sticking through the middle of the retainer about 3mm. They should all be perfectly even, if any look lower there's a good sign of a retainers cracking. This is something you should check if you own an AP1 ( 2000-2003 are the problem years) but I would also check the 2004s as Honda sometimes carry parts over

The picture below shows the one on the right sunk down and lower than normal.



This picture shows the one on the left about to break.


Check over every valve tip, make sure they all look even.


If the retainer breaks the valve will drop into the cylinder and cause major damage. Usually destroying the piston, sleeve and sometimes the head.

See below, these pictures are from a valve dropping.





Once the retainers are removed this is what they look like . These are the worst ones we have seen. This car came from Miami like to this for us to diagnose a noise with a miss fire issue.This guy was so close to dropping multiple valves.
This is the retainer from the under side, usually the cracks are hair line and hard to see. These are ready to break in half.


The Fix:
Replace with OEM AP2 Retainers and keepers.

We supply and install AP2 retainers and keepers for $399 ( to S2Ki members), this includes parts and labor. If you have over 100K this would be a good time to replace valve stem seals too. Ap2 retainers are much thicker around the spring area and still happy turning the motor to 9k, we have never seen a failed AP2 retainer.

I hope this gives people an insight and what to check for.

John

 

Great info

 

 

Dang! I wanted to get mine in before the track day on the 10th.

 

Awesome!!!!

 

He who watches over us...

 

Requiem,

Pull your valve cover and take a look, if any look out of place do the retainers and keepers ASAP. If not , don't panic. Do it later for a piece of mind.

 

John, I think I'm going to have you do springs and retainers for me after the track day. I'm going to order some Supertech dual springs. And I might as well have the seals checked. My mileage is well over 100k.

 

Unless your running boost or aftermarket cams the stock valve springs are fine and good to 10,000rpms. The OEM springs don't put unnecessary seat pressure on the valve and valve train components or cause addition wear.

 

It's information like this that I find invaluable as an owner \ enthusiast that I would not normally be exposed to.