Mercedes-Benz Forum banner

2004 E320 oil loss

2K views 9 replies 5 participants last post by  unimog_jason 
#1 ·
One of my E320s has developed an oil loss issue. Right now it would appear I'm loosing about 1 litre per 50km.

I did some poking around and I can see a pool of oil in the valley at the rear of the engine. The appears to be running down the passenger side of the transmission and onto the belly pan.

I can't see any signs of the cam plugs leaking and I'm doubtful that it's coming from the crank seal and is getting slung around by the flywheel and ending up in the valley.

Has anyone ever seen anything like this before?

Jason
 
#8 · (Edited)
Upon further inspection I was able to see oil pooled in the valley from the front of the engine this morning.

I pulled the intake manifold off and there is about an inch of oil laying in there.

I was able to mop up most of the oil with towels but I can't see a clear source of the leak. The heads are dry, so it's not from the top end. The underside of the intake manifold is dry, so it's not spraying out. The best I can figure is that it's either coming from the threaded bung at the front or one of the gallery plugs next to the knock sensors further back.

Has anyone seen anything like this before?
 

Attachments

#9 ·
I did more cleaning and searching this afternoon and I'm pretty confident that the threaded bung is the problem.

I put some gas into each of the cups and let it sit for a couple hours. When I checked, the front bung was dry but the middle and rear were still full.

Due to the rust, I haven't been able to get the bung out, I think I need to find an 18mm 12 point socket and pound it on. If that doesn't work, the welder will come next.

Jason
 
#10 ·
Ordered the parts from my nearest dealer since their prices were pretty much as good as anyone online, didn't involve any cross boarder shipping and arrived in 3 days.

The temperature was above freezing today so I extracted the bung from the engine. In my case the old bung was so rusted there was no way to get it out with a socket. I opted to tap it out with a cold chisel which worked, but I under estimated the softness of the stamped steel and the even soft aluminium casting under that.

Long story short, I nicked the o-ring sealing surface and took a small chunk out of the side of the casting. A rifling file cleaned up the worst of the nick and a little JB Weld should deal with the missing piece well enough for the remaining life of the car.

I inspected the old bung and found a pin hole on the side from the rust. Not sure why MB would use a cheap piece of stamped metal for the lubrication system, but I guess under most circumstances, it's good enough.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top