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Topic: M11 Oil Leak from the plug at end of block? (Read 779 times) previous topic - next topic

M11 Oil Leak from the plug at end of block?

I'm not really sure what this particular cover is called at the end of the block. It's the housing for the gears coming off the camshaft that drive the different pulleys. There's a plastic plug in the center that appears to be leaking. I assume it's due to oil sloshing around in the block as the gears turn. The plug feels brittle and I'm hoping it's as simple as sourcing a new plug and replacing. Has anyone encountered this? The oil you see on the cover in the attached picture is from about 3k miles of driving.

I'm a little surprised that there's enough pressure behind there to make the oil spray upwards above the plug as it leaks out.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: M11 Oil Leak from the plug at end of block?

Reply #1 –
Pretty sure that is not oil spray but just capillary action causing the oil to move upward. My engine looks the same and your right, we need to replace that cover.

Steve
Steve & Sandy
2003 U320 4220 WCDS, build#6160
Motorcade #17794
USMC '67-'71

Re: M11 Oil Leak from the plug at end of block?

Reply #2 –
Quote from: SteveB –
Pretty sure that is not oil spray but just capillary action causing the oil to move upward.
That makes sense, good call out. I'm curious what the little plug is for... seems you could maybe just replace that instead of the whole cover. I briefly looked through my M11 shop manual and couldn't find any info on it
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: M11 Oil Leak from the plug at end of block?

Reply #3 –
The gear cover plug is Cummins PN 3892666
Greg & Cathy
2000 U320 4010 DGFE Build #5650
Had: 1999 Tradewinds 7370

Re: M11 Oil Leak from the plug at end of block?

Reply #4 –
Quote from: MisterEd –
The gear cover plug is Cummins PN 3892666
Amazing recall, bravo!

A quick google search indicates they're hard to source here in the US but readily available in China. I'll give my local cummins shop a call tomorrow and see what they charge for one.

Is replacing it as simple as prying the old one out while the engine is cold and pushing a new one in?

What's the point of this plug?
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: M11 Oil Leak from the plug at end of block?

Reply #5 –
Yeah, a Cummins shop is your best bet.

It probably has a lip on the backside for retention. Since it's old, be careful not to break the lip off when prying it out.

I have no idea why that hole/plug is there... could have been for some option not used on our CPL.... or maybe access to a screw???

Greg

Greg & Cathy
2000 U320 4010 DGFE Build #5650
Had: 1999 Tradewinds 7370

Re: M11 Oil Leak from the plug at end of block?

Reply #6 –
If I remember correctly it is to access the cam gear timing marks (?).

Steve
Steve & Sandy
2003 U320 4220 WCDS, build#6160
Motorcade #17794
USMC '67-'71

Re: M11 Oil Leak from the plug at end of block?

Reply #7 –
Oooof. 37 minute estimated wait right now when you call Cummins parts department.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: M11 Oil Leak from the plug at end of block?

Reply #8 –
One of my plugs is leaking about the same as yours and it was replaced about 40K miles ago.  Probably have a finite life expectancy.  If you find them get two.

Re: M11 Oil Leak from the plug at end of block?

Reply #9 –
Quote from: Roger & Susan in Home2 –
One of my plugs is leaking about the same as yours and it was replaced about 40K miles ago.  Probably have a finite life expectancy.  If you find them get two.
For shiggles, I put in an RFQ on Alibaba to see what the per/unit price would be if we did a bulk buy. Seems to be $5-$10/ea. I'll update this thread when I know what Cummins charges and what China charges
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: M11 Oil Leak from the plug at end of block?

Reply #10 –
Quote from: Elliott –
For shiggles, I put in an RFQ on Alibaba to see what the per/unit price would be if we did a bulk buy. Seems to be $5-$10/ea. I'll update this thread when I know what Cummins charges and what China charges
So they're $8.30/ea from Cummins and about a $1 from china + shipping. I placed an order over the phone with the Cummins corporate customer service center and it'll be ready for pickup here at the Avondale Cummins later today.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.