'89 560SL Engine Overhaul - Need Opinons

[dsutton01]

My 89 560SL's engine has had some problems during the past 8 months or so: I first noticed a clicking noise originating from the driver's side, kind of loud, rhythmic - in time with the engine RPM. At about 30 second intervals, it fades out for about 5 seconds then comes back, and repeats.

Months after I noticed the noise, a small oil leak developed. Each time i drove it from being cold, i could smell burning oil (and occasionally see some smoke from the front fender, so i knew it was dripping onto the engine somewhere. Also, each morning, i saw a very small puddle of oil under the car.

I finally brought it in to a mechanic to have a look and here's what he told me after removing the valve covers:

The car needs two new cams plus tappetts and a complete head set (with the heads being removed, machined, new gaskets and seals). He said the cams are both worn out.

He also told me my transmission seal is leaking. He tells me that he wants to pull the engine out and fix it when it's out of the car, as that will make the job easier as well as make it easier to fix the tranny seal.

I've fixed a few things on my own, but if you can't yet tell, i'm not that mechanically inclined when it comes to engines. I think this job is going to cost over $1,200 to do, so i'd like some opinions from the community to help me figure this out, and help think of things i may not have considered.

I appreaciate any and all feedback.

[Strife]

Unless your mechanic works for minimum wage and/or gets parts from Midnight Auto, this would cost a lot more than 1200 IMHO.

How many miles are an your car. Has it always been maintained well (do you know?).

[ctaylor738]

The way I score it:

Heads rebuild - 950
Gaskets + misc 250
Cams 700
Rockers 300
Misc (motor mounts, belts, chain, tensioner, rails, whatever) 300
Labor to r/r heads 1650

Thats $4100. It is true that pulling the engine makes it easier to get the heads off, but I have never known anyone to do it simply for that reason. If he will do all this and pull the engine to fix the trans leak for $2000 in labor, it's a good deal.

[Roncallo]

How many miles are on the car. $1200. You cant buy the parts for that much. The dealer around hear wanted $3500 to replace just the head gaskets, and that was without installing inserts.

John Roncallo

[dsutton01]

I apologize - he had told me $1,200 when we were talking about some simpler work, and this time, he was working on a quote and hadn't given me a final price yet, so i correct myself. I don't know how much it's going to cost at all, but i'm a bit frightened after reading the replies to my original post.

The car has 154,000 miles, and has been maintained quite well thus far. It still runs great, starts immediately every time, delivers decent fuel economy, doesn't smoke. Aside from the oil leak and the clicking, it's fine. I don't think i'm ready to spend over $4k on it.

If the oil leak is from the heads, then i'm pretty much stuck aren't I?

[Strife]

A lot of the leak, if you are lucky, may be in the valve cover gaskets. I dodged a bullet changing mine, and retorquing properly with the proper crush washers. There is a temptation to keep tightening loose valve covers, which doesn't help the dried shrunken gaskets seal and simply warps the covers (sometimes permanently), actually making the leak worse.

Did you actually see the cams? were lobes heavily scored or missing chroming? Has this car been well-maintained its entire life?

[KCM]

I am in the middle of the same situation, though I am doing the work myself. I'd be skeptical about the camshafts being worn out, especially if it still runs good, doesn't miss, and has power, as my car has nearly that many miles and the cams still look very good. I have diesels well into the 200,000 mile range with the original camshafts. (FYI, new rockers or tappets are recommended with new camshafts.) The oil smell and smoke is likely just bad valve cover gaskets dumping oil onto the exhaust manifolds, a minor easy repair. I'm willing to bet the clicking is a bad hydaulic valve lifter. These repairs can be done with the engine in the car and no major disassembly.

I'd also bet that with that many miles it could use a new set of valve guides, as in the process of repleacing the valve guide seals, I found the guides to be excessively loose. They look to be made of brass or some kind of alloy which would wear faster than the hardened guides used in most engines. This can cause increased oil consumption or fouling of the spark plugs. Loose guides can quickly be checked by removing a rocker and seeing if the end of the valve can be moved side by side. A small amout is okay, but I think the limit was around 0.25 mm before replacement. So a valve job might actually be a good thing to do, but I wouldn't say mandatory.

Pulling the engine/tranny unit out is actually not as difficult on that model as I had expected. I got it out in a day, taking my time as I was not familiar with the car. Someone who worked on one before could do it in a half a day easy. And it is nice to have the engine out in the open instead of packed into the engine compartment. I'm not sure what seal he is talking about on the transmission, but most likely it is the front or rear. The rear can most likely be replaced with the engine in the car. The front would require splitting the engine from the transmission, easier with the engine out. I could see him wanting to pull the engine/tranny out just to make it easier for him to work on, and while out, I'd replace the front tranny seal.

Do some research. Price the parts on this site, assume the mechanic will need to mark the parts up by 25% or 50%, and get a labor estimate from him. A valve job should only require head gasket sets, probably new valve guides, valve cover gaskets, and valve guide seals. If you take it to a Benz dealer, hold onto your wallet. Their parts prices are much much higher than you will see on this site, and labor is high as well. At the dealer, you would be talking thousands rather than hundreds of dollars.

Has the timing chain and upper guides been replaced? A valve job would be a great time to do that too. This would require a new chain, the three upper guides that go in the head (cheap), a new tensioner, and a tensioning guide. From what I've read, these engines can break timing chains, and after 100,000 they should be replaced as preventative maintenance. If the chain breaks, the engine pretty much self-destructs.

[Roncallo]

Originally Posted by KCM

I am in the middle of the same situation, though I am doing the work myself. I'd be skeptical about the camshafts being worn out, especially if it still runs good, doesn't miss, and has power, as my car has nearly that many miles and the cams still look very good. I have diesels well into the 200,000 mile range with the original camshafts. (FYI, new rockers or tappets are recommended with new camshafts.) The oil smell and smoke is likely just bad valve cover gaskets dumping oil onto the exhaust manifolds, a minor easy repair. I'm willing to bet the clicking is a bad hydaulic valve lifter. These repairs can be done with the engine in the car and no major disassembly.

I'd also bet that with that many miles it could use a new set of valve guides, as in the process of repleacing the valve guide seals, I found the guides to be excessively loose. They look to be made of brass or some kind of alloy which would wear faster than the hardened guides used in most engines. This can cause increased oil consumption or fouling of the spark plugs. Loose guides can quickly be checked by removing a rocker and seeing if the end of the valve can be moved side by side. A small amout is okay, but I think the limit was around 0.25 mm before replacement. So a valve job might actually be a good thing to do, but I wouldn't say mandatory.

Pulling the engine/tranny unit out is actually not as difficult on that model as I had expected. I got it out in a day, taking my time as I was not familiar with the car. Someone who worked on one before could do it in a half a day easy. And it is nice to have the engine out in the open instead of packed into the engine compartment. I'm not sure what seal he is talking about on the transmission, but most likely it is the front or rear. The rear can most likely be replaced with the engine in the car. The front would require splitting the engine from the transmission, easier with the engine out. I could see him wanting to pull the engine/tranny out just to make it easier for him to work on, and while out, I'd replace the front tranny seal.

Do some research. Price the parts on this site, assume the mechanic will need to mark the parts up by 25% or 50%, and get a labor estimate from him. A valve job should only require head gasket sets, probably new valve guides, valve cover gaskets, and valve guide seals. If you take it to a Benz dealer, hold onto your wallet. Their parts prices are much much higher than you will see on this site, and labor is high as well. At the dealer, you would be talking thousands rather than hundreds of dollars.

Has the timing chain and upper guides been replaced? A valve job would be a great time to do that too. This would require a new chain, the three upper guides that go in the head (cheap), a new tensioner, and a tensioning guide. From what I've read, these engines can break timing chains, and after 100,000 they should be replaced as preventative maintenance. If the chain breaks, the engine pretty much self-destructs.

If you pull the engine out of the car also do the lower guides, oil pump chain, front and rear seals and front transmission seal

[KCM]

Done and Done (except for the tranny seal). The guides were the main reason I pulled it out. The tranny was "resealed" a few years ago by a previous owner with mimimal miles since then, so I left it alone. Thanks for the advice.