Interesting Oil - Coolant Leak - Ram Jet 350

[phantom4]

So I have just completed my frame off resto on my 70 K10 and am sorting out the little bugs. Running a new 350 RamJet and 700R4.

Background: Fired the engine a few weeks ago and forgot to plug the oil port above the oil filter, so Old Faithful shot oil into the frame which careened back onto the block and created quite a mess. I also ran a small amount (few tbsp's) of coolant along the intake and cylinder head on the driver side while fixing a coolant leak.

So I noticed I had some oil and coolant dripping from the trans inspection plate and chalked it up to the initial instances described above. So I dropped the plate and cleaned it all up and expected it to go away. Today I am working on some minor fixes and decide to perform the 30 mile oil change. The oil comes out clean, no coolant in with the oil. While draining the oil I notice there is some oil and coolant coming out of the transmission inspection cover. The amount is enough to drip off the cover but is not profusely leaking.

I pull the cover off and find the same scenario, a small amount of oil and coolant is present in the bottom of the plate. Looking up at the engine I find some oil and coolant on the bottom of the oil pan gasket to rear main block. Curious I sweep the back of the engine from each side with a clean hand and I come up with no source, cylinder heads, valve covers, intake manifold, oil sending unit, distributor, oil port plug, oil filter, all of the external stuff is dry.

I take a closer look at my flex plate and notice on the transmission side of the plate there is sign of the coolant streaking down in about 4-5 spots. It appears that when I stop the engine a small amount is running down, the runs appear vertical, not circular. The oil does not seem to originate here.

So I am wondering where this crap is leaking from, any thoughts? I never took anything off the crate and checking all of the obvious bolts I am coming up with everything to torque spec (oil pan, valve, covers, intake manifold, cylinder heads, etc).

It would be nice to assume this all from the initial errors but I think I may a have a larger issue on my hands, I would normally expect the crate to not leak internally, at least the others I have worked with have not leaked.

[phantom4]

Here is the location I am finding the coolant. I let it sit overnight and there is now a small amount of coolant present between the oil pan gasket and the oil pan.

[marcsRX]

Wish the bottom of my truck was that clean.

[Sinister]

Freeze plugs?

[phantom4]

Gratuitous under carriage shot.



From the top.



It is only this clean now as I just finished the rebuild.

I have been leaning towards the freeze plug idea as I can not reach them with the transmission installed. This engine has been running pretty warm during the break in so it is likely the increase in internal pressure that is pushing fluid out. If it continues I suppose I will have no choice but to pull the transmission out and start checking.