1999 500SL, 1988 SEC
The adjustment is this. Those pucks are different thicknesses and by using a go no go gauge you put in the correct thickness puck. Search for my post on valve job.
Holy Crap. I found your post about your adventure with your valve job and puck, rocker, compensator adjustments. Wow. How is your car running since? Have you figured out the go/no go variances you were seeing?The adjustment is this. Those pucks are different thicknesses and by using a go no go gauge you put in the correct thickness puck. Search for my post on valve job.
That's what these old cars are all about, isn't it? one small thing after another then BLAMMO!! something big, just to keep things interesting.Car is running great. Still working on little things though
Knocked off work early tonight and tore into this project. Looked at all the lobes on both cams, and found one, in the exact area the noise was coming from that has very noticeable grooves and scratches that can easily be felt with a fingernail going crosswise along the lobe. I have included a picture. It was kinda hard to get a clear, close up pic, but you can see the scratches. I'm pretty sure I need a new cam. Thoughts?Ok here is what I would do. First you have to decide if its a cam lobe or not. It its a cam lobe, or worn rocker then its time for a new cam, and if you do that all new rockers. Typically you can't mix old with new and get good results. From what I see, and the pictures are not good, the cam seems serviceable, which tends to lead to a hydrauilic compensator. So you have to find which one it it. If you do the hammer test, or use the stethoscope you should be able to narrow it down. If its a compensator I would just change that one and leave all the other old parts in. That way you avoid fixing the adjustment pucks and doing the measuring. This would be the least expensive option too. I would also make sure you get the right oil
Now as to mine, it runs well but I still have a little lifter noise. I think its inherant in these engines to have some. I expected it to be super quiet like a Ford OHC but its not. American lifters have a lot more valve adjustment and no pucks, unlike the German counterparts. Good luck
I think I need a new cam. Do you think the existing pucks with new rockers, compensators and a cam will still give the proper measurement with the go/no go thingy? Should I get a small selection of different sized pucks?Very good advise. Even with high mileage on these engines the wear on the pucks is minimal. There's really no need for puck measurements unless the valve seats have been reground.
Yes, I don't want to half-ass this project. It's going to be given back to my dad for his 75th, so I've got to make sure it's safe and reliable. I just hope I can get it done in 2 years!The only reason to change a rocker is if it's badly worn. Chances are, if you find one you're going to find the cam worn too.
Do NOT mix up the rockers and put one back in any spot other than where you found it.
If you replace a compensator, I would recheck the shim. Chances are it will be acceptable, but if it isn't your just bring on more trouble.
There really are no shortcuts if you want it to be right.
As I've already ordered 8 new rockers, I'll just replace them when I install the new cam. I have a ton of questions about that process, so I'll spend some time perusing the forum to see what knowledge I can gather, but will probably end up starting yet another thread about it. Any advice for getting the cam lined up properly with the timing chain so all the internal bits open and close when they are supposed to?I think we are all on the same page. It looks like you need a new cam. I suppose you could try a used one but thats a mix and match roulette. So if you get a new cam I would use new rockers. Using old rockers with a new cam is usually not suggested. If it were me I also would change that one compensator just because. At first go I would use the old pucks just where they are at and see whats up. Those pucks are expensive. You really are not changing the valve stem length like I did so your variability is much less. My guess is the tolerances on mb rockers is very minimal.
now on the flip side, if you don’t drive much a used cam and rockers can work. Changing a cam is not easy.
John, a question I always wanted to ask you is, can you polish these cams like you do a crank or is the hardness just too thin?