ND2020

I've noticed a leak in this area once before and I cleaned it off because I could not track it. Just checked it again today and STILL cannot pin-point the leak. Are there other common leaks on the m112 other than the breather covers and valve covers? I did notice I have a slight leak coming from the back of the passenger side valve cover, but could not see a trail of it wicking down to where I am seeing this:

(Not the greatest picture, I know)


The driver side of the motor is bone dry, but besides the slight leak I can see from the passenger valve cover...I am stumped. I resealed the breather covers last fall and so far those look to be good. We pulled one of the the torque converter plugs there is case anyone is wondering, it's not missing. I'm going to clean the area again and monitor it, but wanted to check if there were any more common leak spots on this particular motor before proceeding. I honestly cannot tell if it's motor oil or transmission fluid.

Glyn M Ruck

These banjo joints on the transmission cooler are known to leak. I'm not convinced this is your problem. Could be a rear crank seal. The only way is to clean everything & monitor. The breathers & the cambox covers are the most common leaks on the M112.

KalC240

While changing the oil this morning I also noticed this mysterious leak. I used a paper towel to wipe the area and it's more like motor oil than ATF. I used a flash light but did NOT see any trace of oil leaking from above. I need to figure out exactly where the crank seal is located.

Is it possible for motor oil to come out of the torque coverter plugs?

ND2020

Thanks for the input Glyn. I will clean and monitor it to see if I can figure it out. I don't think it's those banjo joints that you mention either. I'm really hoping it's not the rear crank seal. As far as I could tell, it's dripping off of the transmission onto that cooler line because it was saturated around those two rubber plugs. It's obviously a slow leak, but enough to warrant the investigation.

ND2020

Assuming this is the seal Glyn is referring to (119), the transmission has to be dropped to access it:

Glyn M Ruck

Yes - If it is the rear crank seal or the front transmission seal you need to pull the transmission. That's why it is important to identify the leak. Also check the rear oil level sensor for leaks. Fairly common!



https://mbworld.org/forums/c-class-w...l+level+sensor

Ribo89

Glyn-I also have a sloooooow leak at the "rear crank seal or the front transmission seal." Should I be worried and what are the possible consequences if I don't replace the seal?