hello fellas (and ladies where applicable),
this is my first post on this BB and i hope that my time here will be well spent and full of greasy, diesel smelling engine work. here is my predicament:
about 2 weeks ago, my 240k+ '77 240D decided it was time to enter the mercedes great beyond. yes, the compression was too low to even think about starting. i think it actually laughed at me when i kicked her over the morning of her demise. however, i have not given up on the poor lass. i am determined to rebuild! i have prior engine rebuilding experience and believe myself to be fully capable of the task. however, i would like to be completely sure about what i am doing before i dive in. my question is this:
what must be accomplished in order to ensure good compression upon completion of my rebuid? i've heard that these engines have cylinder sleves that can be replaced. should this be done? should i replace the pistons and rings as well? or just the rings? or, just the rings all together. please help.

thanks in advance,
william gum

Bamboo77,

Rebuilding one of these engines is expensive. Yes there are sleeves available, but these are dry sleeves that are used at the machine shop. They are not replaceable in frame like those in a Cummins or other wet sleeve engine. The sleeves are available so that you can repair a cylinder that may have been ruined by some sort of rod breaking mishap.

Your best bet is to bore to the next oversize, and use NEW pistons and rings. The crankshaft is hardened like most all diesels and unless there has been a run with no oil incident in the engines life, you will most likely not have to do anything to the crankshaft.

With the shortblock properly bored and put back together, the success of your rebuild is all in the head. Replace the valveguides no matter what. If the cam and followers look good, you will probably be okay leaving them. It is easy to replace the camshaft at any time anyway.

Best of luck, and keep us posted on success,

------------------
Larry Bible
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in
Mercedes automobiles

Gee Larry, I can't add much to that. Exactly the way I would do it.

All thats left is finding the parts, right and getting a good machine shop to prepare the old pieces.

Larry,
thanks so much for the quick reply. sounds like it is a fairly easy job, pending the shape of my cylinder head. the overall shape of the engine (in my mind at least) is good. nothing detremental happened, it just plum wore out. do you know of a parts supplier that would definatly carry oversized pistons? i should be ready to pull the engine next week (should i be able to find a garage to do it in...) so i'll be in touch about that. thanks again guys,
william gum

Pistons are very expensive. Usually the only part of piston that is worn is the ring grooves. They can be rebuilt by a competent machine shop.
This might not be as good as new, but how much longer are you going to keep this car before the body becomes unacceptable?
P E H

You can get all the pieces from the parts shop here. Order your pieces as soon as you get the engine apart and do your measurements. This will give parts shop time to get the pieces while everything is at the machine shop.

Good luck,

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Larry Bible
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in
Mercedes automobiles

Larry Bible is exactly correct. If you can,bore the sleeves and put in new pistons. They come with rings and pin.The crank is probably good, but to be sure, have it checked and put in new bearings(mains and rod).Be sure you torque and re-torque the head as stated in the MB manual. If I can you in any way, just let me know. Glad to help. You can get all the parts you will need from one of the MB parts houses in Atlanta and save a lot of money. They are MB parts and I have used them since 1967 and I have rebuilt umpteen dozens of MB engines. Most were diesels.
Bill Lewallen Lexington<Ky.