[64speed]

I’m gonna put head gaskets on and if that doesn’t fix it i guess I will sell whatever of that engine is salvageable and look for another block or heads

[TB1]

Originally Posted by 64speed

I’m gonna put head gaskets on and if that doesn’t fix it i guess I will sell whatever of that engine is salvageable and look for another block or heads

was the most recent block that you used after the lifters left the building the first go around not verified good before having the machine work completed? if the car was not severely overheated at some point I would thing that the heads and or block would not be cracked, I can see maybe a head gasket a retorque of the heads as suggested but not the need for another engine.

[b-man]

Did you remove the timing cover and replace the gaskets ?

If there is one design flaw in a Pontiac V8 it’s the fact that a gasket breach in the timing cover at the block face can send coolant into the crankcase. If the timing cover has enough rot it can do this too.

Exactly what services did your local Pontiac guru perform?

Whatever you do be sure to drain all the coolant out so it can’t mix with the oil then flush out the water/coolant mixture by running it a few minutes with some cheap oil then drain it out.

[64speed]

I paid a mechanic to put a new timing cover gasket set on it because I thought that’s where the water was coming from.

[68WarDog]

David do a,compression test to rule out head gasket. You don't want the engine sitting with water in the cylinders. This hobby can test your patience, but I know you'll overcome.

[64speed]

I am gonna pull the heads ASAP

[Lemans64]

Is it possible that the head that was on the right bank on previous build got damaged by the failure? Coolant leaking from that head into pan?
Would not think that hey would pressure check head?? Just a thought. But this SUCKS big time.

[Gach]

This sucks big Time! Wish you were close I’d check it all out for you. Here’s a good possibility and I’ve see this a few times. Possible that it’s the timing cover itself is leaking. I’d pull that first and make sure it’s not leaking in water pump housing. Got nothing to lose by pulling that.

[JSchmitz]

Get a kit and pressurize the coolant system. Find the leak before you start pulling it apart.

[geeteeohguy]

Originally Posted by JSchmitz

Get a kit and pressurize the coolant system. Find the leak before you start pulling it apart.

THIS, THIS, THIS. A pressure tester and/or block leak tester will tell the story without yet even more invasive tear-down.

Or take it to a competent mechanic and pick it up when it's fixed.

[JSchmitz]

Did you do a compression test?

[64speed]

There was only a small leak at the thermostat housing. It’s putting major compression in the coolant system. My builder is a stand up guy and is gonna fix it and anything damaged for free so it’s coming out and going back

[geeteeohguy]

Originally Posted by 64speed

There was only a small leak at the thermostat housing. It’s putting major compression in the coolant system. My builder is a stand up guy and is gonna fix it and anything damaged for free so it’s coming out and going back

The thermostat housing doesn't connect to the combustion chambers unless there is a leak in the combustion chambers. A leak at the T stat housing will allow coolant to escape, not build more pressure in the system.

[JSchmitz]

Glad to hear your story take a positive turn! I can totally relate. I beat my car like a rented mule for decades with hardly any problems. I finally bought aluminum heads that I wanted forever. Then, a week before I was going to install the heads, my 15 year old'ish cam wiped a lobe. Tore it down to the block and cleaned it all out. Installed another cam and it wiped out a lobe on break-in. Tore it down to the block AGAIN and cleaned it. This time I installed a roller cam and associated springs and hardware. It ran like an animal!!! A short time later I found coolant in the oil. Had a big crack in #7 cylinder wall!!! I was so mad that I didn't even look at the car for months. That's why there's a 2000 Chevy 5.3 in my engine bay now. Did what I never thought I would do. But I was wore out. Next is an LS upgrade! Keep the Hot Rodding faith and good luck!

[64speed]

Ok my machinist is gonna rebuild it for free. Before I drop it off what should I tell him to order for the cam? 3.70 rear gears, .64 overdrive, and 26 inch tall tires.

[Singleton]

Why do you need a cam? Isn’t the one in the engine brand new with maybe a couple hours run time on it??

[TB1]

Originally Posted by Singleton

Why do you need a cam? Isn’t the one in the engine brand new with maybe a couple hours run time on it??

ya what Singleton said, how do we go from a leak on an oil filter adapter to the crankcase full of water from a timing cover gasket leak, then to "There was only a small leak at the thermostat housing. It’s putting major compression in the coolant system" to now what cam should I get for my third engine rebuild....... what's missing here

[NeighborsComplaint]

You need to slow down and assess what happened this time and determine what and who was at fault. If your exhaust wasn’t billowing white smoke just before you shut it off, then coolant was not getting into the combustion chambers. That rules out head gasket failure, and intake gasket leakage.

The gasket between the block and timing cover can leak around the coolant passages in the block and can allow the coolant to get into the oil pan. The coolant transfer tubes could have been omitted altogether or the O rings not installed on them but the resulting leak would have occurred immediately and the motor would have failed during break-in. You paid someone to replace that gasket which should have corrected the problem.

This all assumes everything was assembled correctly, ran fine during break-in and delivered to you without contaminated oil.

A head gasket leak typically leaks coolant into the cylinder and may weep down the side of the block also. A leaking intake gasket typically shows coolant puddles in the valley pan and leaks coolant into intake and exhaust ports that finds its way into the cylinders. Coolant turns to steam as the motor runs and a portion of it gets pushed out the tailpipe as thick white smoke and some leaks into the oil pan. No smoke, no coolant in the cylinders, no intake or head gasket issue.

There is always the outside chance the block was cracked through to a water jacket and leaked coolant internally. However, that would have occurred on initial startup and contaminated the oil during break-in.

Take it back to your builder.

[Joe's Garage]

1) pull out ALL the spark plugs
2) coil wire disconnected
3) radiator cap off
4) a couple of helpers to watch

Pull ALL the spark plugs out and position one of your helpers on each side of the engine bay where they can see the spark plug HOLES.

You sit behind the wheel. Crank the engine over for two or three seconds - doesn't need to be too long.

If there is antifreeze in one of the cylinders, it will blow out, or at least blow mist out of the spark plug hole for THAT cylinder.

Good luck!

[64speed]

I just assume the cam went flat with oil and water mixing so much. He’s gonna rebuild it for free so…