om603 engine -turning by hand - PeachParts Mercedes-Benz Forum

ah-kay · #1 10-11-2011, 01:00 PM

What is the least intrusive way to turn the engine by hand to check for flywheel teeth ( starter is off ) and timing chain? The space is very tight to put a socket on the crank nut. I do not want to take too many thing off.

jonbobshinigin · #2 10-11-2011, 01:39 PM

27mm on the crankshaft is what I have always done. I am pretty sure there is plenty of space.

Air&Road · #3 10-11-2011, 01:48 PM

You might need to try different length extensions, but with the right length you can turn it that way with easier.

That said, REMEMBER, this is a diesel and there is a possibility, albeit remote, for it to start upon turning it. Turn it SLOWLY and you have no worries.

Billybob · #4 10-11-2011, 01:56 PM

Quote:

Originally Posted by ah-kay

What is the least intrusive way to turn the engine by hand to check for flywheel teeth ( starter is off ) and timing chain? The space is very tight to put a socket on the crank nut. I do not want to take too many thing off.

The best access is from below rather than from above where the fan is in the way, you also get a wider swing of the tool you're turning with from below because the crank centerline is lower. On an SDL if your lucky you need to remove the sound encapsulation panel, four 8mm screws. Then a 27mm/1 1/16" deep socket and a flex head 1/2" drive rachet turning the engine clock-wise shold make it pretty easy. With the starter already removed you really ought to be able to pretty easily use a pry bar and lever the ring gear around, you'll probably only move it about 10 teeth at a time and it will take a while but mark the first section you check with a magic marker and then just keep turning it until you're back where you started. With that method although it may seem to be more tedious at least you get to do it standing up rather than on your back underneath the car! Good luck!

Oh Yeah, with regard to what Larry mentioned wire the IP STOP lever down to prevent it from gettting any fuel and starting to pop off a cylinder or two as you turn the crank.

sixto · #5 10-11-2011, 02:13 PM

Hold down the STOP lever so it can't start, or at least won't go very long.

Sixto
87 300D

86-300sdl · #6 10-11-2011, 08:16 PM

Underneath is easier. Wire the stop lever and... Whatever you do keep your head and torso away from the socket wrench handle. i.e. strech that arm out.

Mine kicked over (popped, not full start) and the beaker bar I had attached to the socket almost took the passenger side of the front end off the car off. Now I'm not real religeous but I immediately went out to the street and looked to the sky and said "Thank you Lord for think'n about me...I'm still alive and do'n fine"

ah-kay · #7 10-11-2011, 08:57 PM

Are you guys sure that engine will fire? How about I loosen the hard lines at the injectors first?

It never cross my mind when I did valve adjustments for the 617. I was basically doing the same. It does not seem to be mentioned in write up.

sixto · #8 10-11-2011, 08:59 PM

603s are lazy to start cold without glowing. You can't spin it fast enough to start.

Sixto
87 300D

JHZR2 · #9 10-02-2023, 10:52 AM

Is there a way to view the flywheel teeth on the 603 without removing the starter?

sixto · #10 10-02-2023, 11:41 AM

There should be an access panel at 6 o’clock to get to the bolts that hold the torque converter to the flex plate.

Sixto
05 E320 wagon 204K miles

JHZR2 · #11 10-02-2023, 01:00 PM

Quote:

Originally Posted by sixto

There should be an access panel at 6 o’clock to get to the bolts that hold the torque converter to the flex plate.

Sixto
05 E320 wagon 204K miles

Thanks! I just haven’t been under there for a while to be able to remember…