Milky oil after 1984 K10 305 top end rebuild.

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bucket

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The ridges between head surfaces at the front and back of the block on top.

I had actually never heard in called the china wall until a couple years ago and it seemed like that's what everybody calls it now, so I adopted it too.
 

AlexK10

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Update on what I got accomplished over the weekend.

Removed the spark plugs and found no moisture on them.

Removed the intake that had the Mr Gasket … gasket and the right stuff; found vanilla milk shake looking oil in the lifter valley. The intake to head sealing surfaces look ok in terms of no pitting. Gasket areas around water ports seemed to have a good seal but its hard to tell when the gasket and sealer rips apart when removing the intake.

Removed the heads and saw that my pistons are stamped with "040" on them.
All bolts had thread sealer.
Observed that the felpro 8510 pt1 head gaskets were in good condition around all cylinders and around all water and oil jackets. What I mean is that all the water holes had stained the gasket with rusty water only on the gasket holes that run water and did not see any of these running/blown/damaged and passing water to any other gasket area or ports. Same observation with the oil drain passages and the cylinders, nothing blown or damaged.

Took a wire wheel to the intake and heads mating surfaces to clean all gasket material. Could not find any cracks anywhere. Used a non-pression straight edge to the heads and did not see any warping.

Will do:

Take the heads and intake to the machine shop and have them checked anyways. But I don't think the leak was through the head and block gasket.

After cleaning the lifter valley I removed one lifter and saw more milky oil in the lifter and the lifter oil feed passage in the block. I will remove them one by one and flush those passages also to remove most of the contaminated oil.

Will take off oil pan and clean everything I can underneath before reassembly.

This may have contributed to the water although I still believe I had an intake leak:
I read on another forum that someone had the same issue with condensation and water in the oil by running the engine on short startups/run times and not having a pcv.

I have only ran the engine for very short periods and installed the pcv only a week before the first post, because I wanted to reduce the condensation Ive always had on the oil fill cap. I also live in a high humidity area.

Ordered a set of Elgin head bolts with sealer.
I have a thick (.120") felpro intake gasket that I didn't use last time and will use now with more of "the right stuff".
Still need new head gaskets.

Should I get another set of 8510 pt1 or a different one?

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AlexK10

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More photos:

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Snoots

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You really should port match those heads while you have them off and take them to the machine shop.
 

illmanners

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Take vehicle to an emissions testing station and with the engine running, have them hold a tail-pipe probe, normally used to check emissions in the tailpipe) over the radiator cap opening with the cap removed. If there is exhaust getting into the cooling system, they will get an immediate reading. If so, pull the heads and disassemble them (or have a reputable machine shop) disassemble them. Once done, have that machine shop magnaflux the heads to check for cracks. If 305 heads have high miles on them and-or have ever been hot (as in an over-heated engine,) in my experience, they are more than likely, cracked.

Regardless of bore size, or over bore, unless you are building a racer, Felpro 8510PT should be your head gasket, placed on a clean,dry system torqued in
three equal increments to its final torque reading of 65 ft. lbs. All head-bolts should be lubricated with clean, fresh engine oil. (Factory recommends 30 weight.) The torque values specified by the engine manufacturer are typically based on oiled threads and fasteners – not dry fasteners.


(Magnafluxing is an advanced procedure that uses strong magnetic fields to test the structural integrity of metals, especially iron and iron-based alloys. The procedure can determine even microscopic flaws in the surface structure of metals, and so is used to check the quality of a variety of metal parts, pieces and tools.)


Hope that helps....I've been building engines for 53-years, never had a come-back for water in either the oil or combustion chamber issue.
 

AlexK10

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Thank you illmanners,

I will have the heads and intake checked at the machine shop.

Yes, bolts will be "lubricated" with the thread sealer on the threads and engine oil under the bolt head.

Should I use the fel pro 8510 pt again or a severe duty head gasket?
 

AlexK10

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Would like to also check for cracks in the block.


Where do they usually crack?
 

clendon1

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You can also pressure test your cooling system with a tester on the rad, when the pressure drops you can possibly hear the air leaking in what area.
 

bucket

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Looks to me like coolant was leaking between the head and intake, at the rear port on the driver's side. It looks like evidence of rusty coolant leaking past the gasket.
 

PrairieDrifter

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Looks to me like coolant was leaking between the head and intake, at the rear port on the driver's side. It looks like evidence of rusty coolant leaking past the gasket.
I noticed this as well, looks very rusty in the middle too.

To the op, is this a factory intake?
 

AlexK10

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bucket and Prairie, I just went back to the photos and see what you pointed out.

Both rear water ports have a rust line, the front water ports look ok although the gasket is in the way.

The center driver's side exhaust crossover, and most of the bottom of the underside center of the plenum has rust; I believe this is from water splashing and condensation throughout.

Will have the heads and intake checked today at the machine shop.

Just ordered a new set of 8510 pt head gaskets. Pending for the gaskets and Elgin head bolts to arrive.

Will use the ticker fel pro .120" intake gasket I have.

Stuff to do before reassembly:
Cleaning of the block surface and threads
Remove and clean the oil pan and lifters

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