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My mechanic said the timing chain jumped and bent valves and maybe even punctured pistons on my 85 380SL, Walked approx $2500.00 to repair. Other problem is its leaking from the main seal. Any suggestions?
 

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Buy a used engine, your old one is toast now. $2500 is probably 1/2 of what it would cost to repair.
 

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Happened to me twice with my '83 380sl before I converted to dual row chain.

There is no reason to believe your engine is toast because you bent a few valves. If there are bent valves then there should also be loose rockers. Check for yourself and see. Worst case, pull the heads and replace the bad valves if you find any. Not likely to have serious damage to pistons but not impossible. Head bolt holes are known to strip when removed... no grantee but it does happen. If so you'll need to re-thread the head with heli-coils or inserts. Search the forum for threads on stripped head bolts.

Mileage is almost irrelevant when it comes to the life of the chain guides... time is the more important factor. Remove the rocker covers and take a look at the guides... if they're dark brown your living on borrowed time. Use your own judgement... when new, chain guides are white... they discolor with age and oil. If the chain guides are 10 years or older... change them regardless.

Don't forget to replace the oil tubes.

Good luck.
 

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Changing to a dual row change has become quite expensive. If you can find an engine, which is in decent shape, which already has it, it will save you a whole lot in both parts and labor.
 

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Changing to a dual row change has become quite expensive. If you can find an engine, which is in decent shape, which already has it, it will save you a whole lot in both parts and labor.
It is not imperative to convert to dual row chain if you've got a single row... it would be a good idea but is not absolutely necessary. The single row chain can be left in place as long as the oil is changed at regular intervals and the chain, chain guides and oilers are checked and changed if necessary but I wouldn't go more than 5 years without at least checking them. It is a lot easier to install a new single row chain than it is to replace the engine.

I wouldn't go more than 10 years without changing the chain and guides if it is single row. It is so easy to check the chain and guides that there's no reason not to check them. Pull the right side rocker cover (passenger side in US) and take a look. The guides will be plainly visible (if they are dark brown change them immediately) and the chain can easily be checked for what people call stretch (it's actually wear) by pressing on the chain anyplace where it is not in contact with the cam sprocket (to take up any slack) and then grabbing the chain at the midpoint on the cam sprocket and see how much play it has by pulling up on it. If it can be pulled up from the sprocket by more than an 1/16th of an inch... change it.

Regular oil changes with quality oil are a must with these engines. You wouldn't believe how much oil is flowing in and around the cam sprocket, the cam lobes, the rockers, the hydraulic compensators and the cam towers unless you've seen it for yourself. I recently cut the top off of a spare rocker cover and bolted it to the drivers side so I could watch for myself. The oil flows like a river up there, it drops directly down on the cam lobes from the oilers above. The oil gets to the oil tubes from the tops of the cam towers and oil is fed to the compensators via holes in the head. No wonder these cars hold almost 10 quarts of oil... a good portion of it is circulating in and around the top end. I couldn't let the engine run for more than a few seconds before oil was all over the place.

Oil filter changes are a must at every oil change... don't go by the old adage that says you can change the filter on every other oil change... it's few bucks and a few minutes of time that are well worth the effort. Maximum lubrication of the top end, which includes the cam sprockets and the chain, is essential to the life of the chain and everything else up there. There's a reason Mercedes designed the oil capacity to be almost 10 quarts, it's best that we keep that oil as clean as possible.

Sorry for going on and on... in the past I abused my engine by not changing the oil frequently and I paid the price with a blown engine twice due to the failure of the timing chain. My ignorance about the importance of frequent oil changes and checking the guides and oilers cost me many thousands of dollars... my hope is to save others from that same fate. :thumbsup:
 

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$2500 for a repair like this seems pretty low. That's what happened to my 380sl back in 02. The cost was crazy like $5-6k.

I'd repair or even take the opportunity to put in a 500sec engine. More go go. I'd do this if I had the garage space.

Was there warning or did it just go?
 

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Buy a used engine, your old one is toast now. $2500 is probably 1/2 of what it would cost to repair.
Not necessarily toast. If you do a proper engine rebuild you will have a machine shop true up the cylinder walls replacing the pistons. You will also have the heads completely gone through. Now would be a good time to refresh the fuel system. And for heaven sake if you have a single row timing chain put a dual row in.

I happen to like my 380SL and would deem it well worth it. Part of this too, is I have engine building experience and can do the work myself, saving myself thousands. You will get a lot miles out a proper rebuild than a salvage yard engine -- which you don't know how its been treated.
 

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I bought a remanufactured long block years ago from a place in Winter Park, Florida - still running strong. Don't know if i can mention Noel's Mercedes or not.
 

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Yep ;

It's replacement engine time unless you're rich .

Plenty of good low mileage engines out there as these cars rust out regularly and get wrecked too .
 

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It actually depends on who you are... if you're a guy like me, and wrenching is in your blood, then rebuilding the engine you've got is the better option. If you're not a wrenching kind of guy then your options are controlled by expense. Rebuild or replace... which costs less and which is most likely to produce a good result?

Both options... rebuild or replace... require that the engine be pulled from the car and then, either a different engine or the original, must be installed. In other words... both options require the same effort in that respect. If the engine is a replacement, assuming that there are no problems with it (how can you tell by looking at it) then you're done. If you're rebuilding the existing engine then all the work involved in a rebuild must be done between removal and reinstall. If your decision was to rebuild then there is no cost for purchase of the replacement engine, but there is the expense of buying whatever parts are required for the rebuild. Simple right?

I don't know it for a fact... but I have heard it said many times... that these engines are bullet proof as far as their metallurgy is concerned, their weakness is in the top end and specifically the plastic (nylon?) parts involved with chain guidance and the tubes delivering oil to the cam lobes. Checking or rebuilding the top end does not require removal of the engine and is a relatively easy thing to do. I say relatively because we must assume you (or your proxy) posses sufficient knowledge and ability in that area (I've been told that converting a timing chain to dual row requires removal of the engine).

If it were me I'd pull the heads and have them rebuilt. New valves and seals, replace any compensators that need replacing (joke) check for excessive wear on the rockers and replace everything that is plastic or rubber anyplace on the top end. If after doing that you still have a problem then the replacement engine is still an option and you can use the rebuilt heads (with all the new plastic and rubber parts) on the replacement engine. After all... those parts in a replacement engine will be 30+ years old just like they are in your current engine.

Best of luck to you... whatever you decide to do. :thumbsup:
 

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How To Proceed ?

And therein lies the rub :

Not all here have the tools and knowledge / experience to tackle this job .

I'm a Journeyman Mechanic and I find bench work, like engine building, to be fun and rewarding .

Many don't and would not enjoy the basic in situ pull the heads and front of the engine to do the valve job and timing chains etc. .
 

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And therein lies the rub :

Not all here have the tools and knowledge / experience to tackle this job .

I'm a Journeyman Mechanic and I find bench work, like engine building, to be fun and rewarding .

Many don't and would not enjoy the basic in situ pull the heads and front of the engine to do the valve job and timing chains etc. .
And therein lies the rub... I have every tool required to do the job and I love taking engines apart and finding what's wrong, sometimes I forget that the same doesn't apply to everyone. :eek:
 

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The Solution

So then ;

Go forth and be merry, share your knowledge freely and widely at it's worthless unless shared .

Maybe you'll encourage others to give it a try .
 

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All of this sounds scary - Do any of you know if the timing chain and guides issue applies to the M110 engine? Built at the same time & has a timing chain. Is there an easy way to check it like pulling the cam covers? I've often heard that the M110 is bullet-proof but, although mine has 45k on it, it's still 40 years old.
 
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