95 6.5f, started milking oil, changed head gaskets to no avail, removed and resealed timing cover, still have issue. I tried adding dye to coolant and black light the oil, but thats not working. Seems to leak into crankcase while parked, without even running...what's your opinion?maybe a cracked block. there was no evidence of head crack issues...????

Never a good situation to find coolant in the oil. By doing head gaskets and inspecting the heads, you have eliminated that, so a cracked block is a logical possibility. Unfortunately, no easy test or cure.

Head bolts or head studs? Did you replace the head bolts when replacing the gaskets?

IF you try and reuse the head bolts, they will leak, no sealant good enough to seal besides the stuff applied on new bolts. Studs have the same problem, almost impossible to seal in these engines.

If what I'm saying here doesn't apply, then I'd recomment just pulling the oil pan with the engine in the truck and see where the coolant comes from, perhaps it's a crack.

Yes, it got all new head bolts, when we replaced the head gaskets.
I got to beleive the block is cracked, but I have never seen one do that before. I did see a 6.5 with the main webs broken, but that was chipped up for more boost

Mainweb cracks do travel up into the water jacket.If the heads tested good,then that is most likely what happened. You are by no means the only one

or the inrad oil cooler? just a thought, when you turn off the truck the oil pressure drops off and the coolant will be under pressure still, so it will pour into the oil lines.

before you qoute me is there oil getting into the coolant as well?

before you qoute me is there oil getting into the coolant as well?This truck has external cooler, no radiator oil cooler.

Ok, I know some of the trucks have a dual set up, so i thought I'd mention it(not sure if it was an aftermarket thing though...hmmm anyone wanna look into that for me?)

IF you try and reuse the head bolts, they will leak, no sealant good enough to seal besides the stuff applied on new bolts. Studs have the same problem, almost impossible to seal in these engines.
.

This is new to me,. not sure what you,re using but i don't have a problem,. with any engine i build,. gas or diesel,. new or used head bolts,.whats so different about a 6.5?
Where did you come up with the facts for this statement?

Nick

the bolts are TTY anyways, so you should be replacing them.

and you should be sealing the ones that go through water jackets.

This is new to me,. not sure what you,re using but i don't have a problem,. with any engine i build,. gas or diesel,. new or used head bolts,.whats so different about a 6.5?
Where did you come up with the facts for this statement?

Nick These 6.5 headbolt holes enter the water jacket,thats why sealant is used on the bolts. They arnt hard to seal either.

Ok, I know some of the trucks have a dual set up, so i thought I'd mention it(not sure if it was an aftermarket thing though...hmmm anyone wanna look into that for me?)No factory in rad oilcooler on a 95.

and you should be sealing the ones that go through water jackets.
and do you know how many of them do??;)

nick

and do you know how many of them do??;)

nick

all 28 of them(14 per head) go into the water jacket