Jp....but did you replace the heat exchanger core of the cooler or just the o-rings.
That core can rupture internally as well.

 

Could it not get in there from the injector cups?

 

Nope just the o-rings. That core is like $250, so I just re-ringed it being as I never had a problem with it.

I did put the melling HPOP on though, which runs a slightly higher pressure, so it's conceivable the cooler could have sprung a leak. I can't think of any easy way to test it once it's off either...

I do have the other cooler on the old engine I could use. Maybe I'll buy the oring kit, pull them both and decide which one to put back on...

 

Not from what I read. That would be fuel in the water.

And oil in the fuel is bad injector o-rings.

It seems to be pretty clear cut based on pressures - what fluids go where when different things fail. This is all based on research alone though. In open to any other opinions that might be out there. Definitely want to make sure I'm fixing the right thing here!

 

Agreed. I did an oil cooler on a guy's truck a while back that had just been rebuilt by another guy. Oil was getting in the coolant on his too. I pulled the freshly rebuilt oil cooler apart and one of the o-rings was rolled over the stop. He must not have lubed them enough when he put it back together.

 

Well that just sucks JP. At least it's not to hard to get at and the bolts won't be seized. Just sucks though

 

Thanks for the post, Bill. Hopefully it's something obvious like that on mine. I think I lubed them good but i'll definitely slather it on this time around. I just whacked it back together with a mallet last time, too. I'll have to find a way to press it together this time.

After this initial sinking feeling that I had an injector cup job ahead of me, I'm feeling better it's hopefully just the oil cooler. Parts are in the mail and I have fri and sat to sort it out.

I've been driving it the last few days and checking the coolant each day. The level hasnt rise any more and there's been no spillage. As long as I don't ride it hard and hot it seems to be ok. I guess that means it's a pretty small leak or that it only opens at full temp.

 

Keep an eye on your oil too JP. Granted water shouldn't go it when it's running and you have oil pressure but when you shut it off the cooling system can hold pressure for a long time.

 

Just for future reference, I've head of some guys having pretty good success cinching them together with a ratcheting tie down strap. Others say they just put one end on a block of wood and lean on them and they pop together.

 

thanks a good point. i've been checking the fluid level every time i shut it off, so i'm bleeding the coolant pressure at that point. i'll be sure to keep doing that!

 

good to know, Nate. its about time i rig up a bottle jack press in the shop anyway, but might as well try the lean-on-it-method first...

 

I used the ratchet strap method, mind you I had the motor out so I just bolted one header to the motor and synched the other in. It worked very well, I'm sure a vice to hold it would work to

 

The ratchet strap works in about 25 seconds, with vaseline for lube. I didnt need to bolt it to the motor or anything, just lined up the two ends and did both at once.

https://www.ford-trucks.com/forums/1...l#post15136835

Scroll down to the oil cooler bit. Seriously it's easier than leaning on it.