Head Gasket/Cracked Block? Rebuild

[83kid]

Hi,
So i have an 83 k10 with a 350, mild cam headers.
Bought a few months back, PO said motor had been rebuilt about 30k ago, reciepts for camshaft and stuff but most of the other stuff is confusing, because it looks to be a GM crate motor (Bolts down center of valve cover)

Leaked or burned oil, not sure, but it wasnt that bad and still is a lot faster than id like it (Every week or so it gets down to add). In the past few weeks, been burning a lot of coolant too, like i have to fill it up because its empty every 3 days. Has a ticking valve like noise on the passenger side, and a little bit of oil comes out through the breather(Very very small amount - can never see any just it has buildup of black oily deposit beneath it, not from the base of the valve cover, the breather)
Saw a drop of coolant sitting on the front of the intake manifold the other day, right next to the valve cover.
Pulled a plug on either side - REALLY caked with a whole ton of white crap, didnt want to idle and if figured thats probably why, getting real ****** spark, so i just turned the idle screw in more for now.

So, i've been thinking its a head gasket (Both), the oil on the dipstick looks good but the oil thats on the bottem side of the fill cap when i open it is a bad milky brown, from the coolant id assume.

Gonna tear it apart soon, replace head gaskets and what ever else seems to need it.

What do you think ill need to do? Only starting with taking it down to the heads, like take the heads off, hoping not to have to go any further and take it down more and take the engine out.
What do you think is causing this and what should i have to replace?


Thanks!

 

[chengny]

It's probably just a HG failure, but it could be a cracked head or even a cracked block. I can't remember if your block has been bored - or by how much, if it has been. Anything more than .0040" over is pushing your luck. Here is a former engine of mine that was bored 60 over:

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Your coolant is getting out and into the exhaust somehow. I say exhaust because it isn't going into the lube oil system.

If it were, at the rate you are losing it, your oil would be milky in a day.

When you pull the heads inspect the gaskets. If you see a point of failure between a cooling passage and a cylinder, you'll know that at least some of your coolant loss was occurring there. But that's all you will know for sure. Without testing the heads (by magnafluxing or dye checking) it will be a gamble to reassemble using just new head gaskets. A cracked block should be able to be visually identified as in the photo above.

 

[Chaz]

Coolant on manifold,,,,you can get/rent one of them radiator pressure testers from oreillys,,,it attaches to the radiator cap and you pump air into it up to whatever the pressure is supposed to be,, like 15lbs or whatever,,,and if theres leaks they usually show up,,,,my truck was squirting coolant out from the upper radiator hose on to the top of the manifold I couldn't figure it out until I used the pressure tester,,,,also it used to leak coolant on the ground and use coolant but somehow it stopped,,,i think it was from the intake manifold near the rear crossover because when I tightened the bolts on the manifold it seemed to stop leaking,,,,

white crap on plugs,,,,fouling,,,i had same thing and I just found out there were no valve seals on my exhaust valves,,,prob causing oil fouling,,,

valve cover breather leak,,,,mine always leaks too around the pcv valve,,,don't know why,,,,

 

[PrairieDrifter]

The pcv grommets usually get hard from the engine heat and always leak.

Did you have any coolant on the ground where you parked it? Leaky radiator or hoses? also check if your heater core is leaking, look on the passenger side floor in the cab and feel if its wet.

 

[83kid]

No leaks at all, never any on the ground, but tons and tons of white amoke in the exhaust, so it seems like its burning it, not leaking from anywhere

 

[PrairieDrifter]

My guess would be cracked head if you have no coolant in the oil, I wouldn't think it would be a cracked cylinder wall because you would have coolant in the oil. Did you check your heater core for leaks?

 

[chengny]

but tons and tons of white amoke in the exhaust,


Nuff' said - head/head gasket.

If you have never let the engine overheat during all this time you have been struggling with coolant loss - you may have dodged a bullet. Your heads are probably fine. These are not delicate, high performance pieces of equipment, they are SBC cylinder heads. They are built to withstand serious abuse and even a certain degree of neglect.

There is even an established procedure for retorqueing a head that has been severely overheated - while it is still smoking hot. No one does it anymore, but back in the day....

Most heads crack not because of overheating but because people panic and dump cold water into the cooling system of an overheated engine. This is what sets up the severe thermal stresses that actually cause the fractures in the webs between the valves.

 

[PrairieDrifter]

whoops I ment to say head gasket is another possibility!

 

[Chaz]

There is even an established procedure for retorqueing a head that has been severely overheated - while it is still smoking hot. No one does it anymore, but back in the day....

I like that lol,,,never heard of it but I like it,,,,I drove a Cadillac 472 eng until it overheated/seized up with a broken radiator hose tryin to get to a fwy offramp. Bought a new hose, filled the radiator up with coolant, and was surprised it started after it cooled off. Ran perfect after that and never had another problem with it.