300D and 300SDL ( 617 and 603 ) engines - PeachParts Mercedes-Benz Forum

ah-kay · #1 03-27-2009, 06:02 PM

Need some info on engine rebuilt with engine in situ in the car. I just wonder what engine work ( ring, piston etc ) can be done without lifting the engine out? Not the crank shaft, I suppose.

Any info would be appreciated. It would be good info to be had.

jt20 · #2 03-27-2009, 07:17 PM

I can only speak for the 617.

you can remove the upper pan with the engine in the car, but by the time you get the engine up high enough, you'll be about 5 minutes away from removing the entire engine.

if you did get it off:

-you could remove the crank - but you'll probably damage it. If you have a helper, maybe more control and less of a chance. You'll have to break off the trans and remove the flywheel.
If you leave the engine in the bay, outside, you risk surface corrosion on you cylinder walls.

-with the crank in and the upper pan removed, you COULD remove the pistons; but you're fighting gravity and you'll probably damage them as well. With a helper and some creativity, maybe you could avoid this - they are going to POP out.

-I would imagine there are some machinists that would deck the block in the car.

-the head can be removed and rebuilt safely.

LUVMBDiesels · #3 03-27-2009, 07:19 PM

As far as I know...

You can do head work on either engine. The turbos can come off with the heads. You can do starters, compressors, water pumps and alternators with the engine in the car. You can also do the timing chain with the engine in the car. Any lower engine stuff like taking the pistons out to do rings, etc needs to have the engine pulled to get the upper oil pan off.

Hope this helps...

ah-kay · #4 03-27-2009, 11:02 PM

I wonder whether it is possible to remove the head, remove the oil pan and push the pistons from below? I have done it with gas engine but that was the most complex job I have ever tackled with engine.

sixto · #5 03-27-2009, 11:11 PM

You have to raise a 603 to remove the pan to get to the rod bolts.

If you're not going to do a proper job, don't touch the bottom end.

Sixto
87 300D

jt20 · #6 03-28-2009, 01:00 AM

Quote:

Originally Posted by ah-kay

I wonder whether it is possible to remove the head, remove the oil pan and push the pistons from below? I have done it with gas engine but that was the most complex job I have ever tackled with engine.

see post #2 ...??

edit: I guess I wasn't clear enough that the head had to be off for removing the pistons.

mash · #7 03-29-2009, 07:24 PM

Can you rebuild an engine while it's still in the car is like asking if you can eat while laying down. You can do it but it's no fun and why would you want to? Buy an engine lift and remove the engine and tranny together and mount the engine on an engine stand. Then get a glass of wine and get to work. What you propose is going to make the job ten times harder and turn something interesting into a stiff back and migraine! Remember in jobs like these cleanliness is job #1 and with the ingress of dirt into your engine from the dirty surroundings of the engine bay all your work could be for nothing when you have to redo the job because a piece of something plugs a piston oil cooling jet damaging the piston and liner! Even a little bit of dirt can cause premature failure of main/rod bearings! With the engine removed you can send the block/head in for cleaning and machine work and then reassemble it yourself. Good luck!