I originally pulled the head because I thought the gasket blew and was casuing my oil leak. But when I was turing her over today to bleed the injectors the oil started coming down the side of the belhousing and block again. That is without it running just it turning over.

Heres a pic to help explain where the leak is coming from


I felt around the back of the block and the leak orignates somewhere below the head like just on top of the belhousing. I felt the cam plug and all around it and it is very evident that the leak is below the area of the cam plug. I have absolutely no clue what is could possibly be from. It definitely isn't the fuel return line or the valve covers and the cam plug and all around it is dry. I can't feel anything else on the back of the block where it could be coming from. It is way too much oil to be leaking to be able to be the rear seal especially since no oil is ruinng out from inside the belhousing just on top.

If anyone has any ideas or even pictures of the back of the block I would really appreciate your help right now thanks and sorry for the long post

 

If you haven't gotten it figured out by some time later Friday afternoon, I'll get a pic of the 90 engine I have out with the adaptor plate and bellhousing off. From looking at my pics with the plate and bell bolted up, I see nothing that could be leaking except the cam plug or a crack in the block. Maybe if you're lucky the tappet cover is spewing oil back that way.... It's at that level, but off to the driverside.

 

I can't feel any cracks at all and it must be something that has high oil psi to be able to come out that fast

 

Are you sure your oil cooler isnt leaking and running down? Its oil not trans fluid?
Maybe the rear main seal is bad?

 

 

Is that a freeze plug on the back? Looks like you have to remove the transmission and hope you have enough space to get at that thing from underneath.

 

Doesn't look like theres any place for it to be leaking. Has anyone ever heard of the blokc cracking back there? It is definitely 100% motor oil
I appreciate the help

 

Well someone beat me to the pic. Yes its a freeze plug, not the cam plug. I uploaded some pics of the rear of the engine with the bell and adaptor removed (view when approved, or PM me your email address, I'll email them to you). I see nothing back there that could leak in the area you mention. Above the cam plug and rear main, but below that freeze plug is a small cap plug about 1" or less. But it would be hidden behind the adaptor plate and bell. I wonder what is behind it, oil rifle?

 

I just reread your 'son of an oil leak' thread. Read this:Time to pull the transmission to get at this leak. Easier than pulling the engine. At least you got all that headwork done.

Edit: my photos are approved.

 

thanks for the pics bill I really appreciate that! Is the rear main oil rifle plug that small plug above the cam plug? I don't understand how all the oil could get through the belhousing and go down the top of the block like that. Would it be easier to pull the motor then to pull the tranny when I don't have a hoist?

 

I don't know if it is, I thumbed just about all the way through the Cummins troubleshoot and repair manual and couldn't find anything on that little plug. Let's say it is. If it was, then like said above, the bell to adaptor plate to engine is not a leak proof/sealed surface. If you had a bad leak there, it could spray up between the surfaces. I think some more research or phone calls to a good engine builder are in order before doing any unnecessary work. I'll go check out a different Cummins book I have in the garage and let you know if I find anything.

As far as hoists or lifts, it would be easier to lower the transmission, clutch and bellhousing with the truck up on jackstands than pulling the engine and all out of the truck. All you really need is a floorjack to pull the trans. Heck all you got is a 2wd trans.. not like you got a heavy 205 bolted to the rear of it. While you're at it, replace the throwout bearing- cheap, and if you got the money, a new clutch $$.

It would be more work pulling the engine, radiator support/radiator got to be pulled, unbolt a few things, then chance the engine hoist failing. Pull the trans, if you can't get to the real problem, then you are 200lbs lighter when pulling the engine if needed.

 

The holes on each side of the freeze plug are threaded, some folks have been able to use a metal bar with holes aligned to the bolt holes to push in a new freeze plug without removing anything.

 

I don't think theres really any engine builders around here that are familiar with the cummins. I think my best bet would be to call cuymmins and speak with service. Other then that I have no clue how to find out where its comming from without dropping the tranny

 

Don`t know if anyone has suggested this but, how about adding some UV dye to the oil to help pinpoint the leak. Not to make a joke or anything but the ferd boys HAVE to do it all the time for the 6-oh`s. I have used it at work and it really helps to pinpoint the source of a leak, especially when you have alot of "collateral" mess.
Napa carries it
http://www.napaonline.com/MasterPage...luorescent+Dye

 

I don't know if that would help chris because when I crank it over a few times to build oil psi and then go out and look theres already oil running all down both sides of the belhousing. So wouldn't the dye just be all over the place? or how exactly does it work?