timing chain inspection
 

my 91 560SEL has 145,000 miles on it and i am having the timing chain inspected as i am not really sure when the rails and tensioners were replaced. my mechanic quoted me $120 to remove valve covers, inspect rails tensioners and chain, put in new gaskets and reinstall valve covers. Is this a reasonable price? Are there other things that i can have him look at while in there?

thx
emmy

Sounds pretty fair to me.

If you opt ro replace the chain and guides, go ahead and replace the oiler tube plastic seals as well. Inspect the cam gears for wear, replace the drive belts while they are off and go ahead and pop a new front seal in it. There are also a set of vent tubes on the injector holders right at the inside base of the valve cover, most sre rotten from heat and age, pop a new set in.




Joe

Don't just check for broken rails. Check to see if the chain is STRETCHED.

Actually it a little high..
 

I just did the inspection. $45 labor plus gasket cost is what I was going to pay. The only problem is I didn't get to pay that price, cause my upper rail was broken and the piece was laying on top of the TC. Couldn't button it back up. Had to put a TC and upper rails on..So inspection only should not be $120...All you have to do is pull the drivers side valve cover and take a look at the upper rail. If it is beer bottle brown, it's time to say good by, before it causes you $6k in upper engine repair.

thx for all your responses.

dave, how much did it cost you for the chain and rails replacement?

tc replacement
 

Well, I had planned to do it myself and I stopped by a friends independent MB shop on the way to my sons Dr. apt. I asked him to check it out. He said it would only be about $40 plus gaskets. so I thought no problem. The fact is, I just bought this 420 and it is my second 420, same year only 80k miles. Paid 5k for it. I knew it was the origional tc and rails but still drove it for 3 weeks rather my wife did. Long story short......when I got back to see what he had found, the upper rail was broken and all other rails were in need of changing. So I was committed cause I could hardly button it up and drive it back home....even though I could have changed it myself. Anyway.....I got out of the shop for $726 parts and labor. That's about right. At any MB dealer it would have been $1300. Never, go there.......with a little researching, you can find a reputable independent mb place....In Sacramento, there are several......You should see the condition of the rails....you would not believe it.....the shop owner said he has not seen a upper rail that has worn through the nylon into the metal. I was beyond lucky and as sad as I was spending $700, If I hadn't stopped in on a whim....it most likely would have cost me $6k in upper end repairs...making me a very sad and stupid guy.