Working out the bugs - PeachParts Mercedes-Benz Forum

imdavid28 · #1 03-13-2006, 09:36 AM

So I have been finishing up putting a 79 SD engine into my 82 300D. Its moving finally, but there are still some issues:

1) What did the 79-80 SD's do with the crankcase ventilation? The old engine (the 82) ran it into the air cleaner and then had a drain from there to the oil pan. The new engine doesn't have this provision.

2) At about 25-30mph I get a vibration which seems to come from the back of the car. It seems to occur only between these speeds. I don't notice it when going faster or slower.

3) How does the pneumatic door lock system work? Mine seem to pop up when ever I start my car, which I know isn't right. Is is supposded to lock all four when the drivers side door is locked with a key, I don't know...

Thanks!

79300sdtd · #2 03-13-2006, 09:59 AM

imdavid28,

In my 80 the crankcase vent goes in under the air cleaner and it looks like it "t"'s back down to the oil pan in one direction and up to the cleaner in the other.

My locks (all) unlock when the drivers side is unlocked and vice versa.

as for the vibration all i can say is get the balance of the tires checked.

hope this helps

Ralph69220d · #3 03-13-2006, 10:04 AM

If the tires aren't the problem, check (if your model has them) the flex disc/s front and rear and the center support bearing. Also ensure that the angle of the driveshaft is that which is specified in your newer drivetrain.

ConnClark · #4 03-13-2006, 11:01 AM

On my 79 300SD the PCV ran into the U-pipe if I remember correctly. Actually I'm pretty sure because It cracked and I had to RTV it up. If I were you I would look at reinstalling the 82's aircleaner.

imdavid28 · #5 03-13-2006, 01:10 PM

Quote:

Originally Posted by ConnClark

If I were you I would look at reinstalling the 82's aircleaner.

Yeah, thats the plan. The only problem is that the ventilation runs into the air cleaner, goes through a separator, then the vapor goes to the manifold, and the oil would normally go to the oil pan. But the new engine doesn't have this tube to go to the oil pan.

rhodes2010 · #6 03-13-2006, 01:42 PM

I swapped in a 1981 motor into a 1980 and had these to deal with:

1980 300D non-turbo motor:
Vaccum pump into top of air cleaner.
Top of Valve cover breather into intake manifold under the air cleaner.
No EGR.
No oil pan return under air cleaner.

1981 300D non-turbomotor:
Top of valve cover to top of air cleaner connection.
Oil return line from air cleaner to pan.
No connection from vacuum pump to air cleaner.
EGR valve on manifolds.

My dilemma was that I wanted no EGR on the motor.
I ended up using the 1980 non EGR intake and exhaust,
1980 aircleaner, valve cover vent to intake.
New motor had no vacuum to air cleaner line so I plugged air cleaner.
Ended up leaving oil return line with nothing attached.

imdavid28 · #7 03-13-2006, 02:13 PM

Quote:

Originally Posted by rhodes2010

Ended up leaving oil return line with nothing attached.

So it just drips the oil onto the ground? Does it drip alot?

I considered doing this at one point, but then I realized the turbo was right under it. I didn't see good things comming of that...

dieseldiehard · #8 03-13-2006, 03:55 PM

You should have drilled the top oil pan flange while the engine was out. Its soft pot metal but you need to catch the drill tailings. Then you can install a return line from the separator to allow the condensate to go back into the sump. Or find a oil pan off a donor engine that already has the opening.