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Discussion Starter · #21 ·
I pressure tested the motor after I flushed some of the oily water out. I pumped it up to 15lbs, Watched the gauge as it leaked down over a period of only a few minutes. I did the test with the plugs out, same result, could see the needle slowly move away from 15lbs. I put four spark plugs in the passenger side head, still leaked down. I put four in the drivers side head, still leaked down. I put some "Blue Devil" Radiator cleaner with oil remover, ran the motor for 20 minutes. Watched the flow through the open radiator neck, and water flowed smoothly, temp gauge only moved to the first mark. When it cools down, I will drain the cleaner out, refill the water, and conduct the Leak Down test again. A little history now. When I installed the motor I used the FelPro gasket set the original owner purchased in 1998. It came with the short block he had rebuilt and stored, until I purchased the car in September, 2021. The head gaskets are metal, with the blue sealant around each cylinder hole. The original owner installed new rings, rod and main bearings. It was not bored oversize. I found no evidence of cracks to the naked eye, and he indicated the car 99000 miles, and he decided to do the rings and bearings. I rebuilt the heads, and they were free from any cracks. I installed a Melling cam and lifter set in May, the cam was properly "broken in", and the motor ran strong for a few days, but developed a soft cam lobe. At that time, there was no oil present in the cooling system. A few weeks ago I installed a "Howards" cam and lifter set, broke in the motor, and it ran strong. Except I discovered the oil in coolant now. That's the story of how I am where I am today. Phil
 

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Discussion Starter · #23 ·
I thought about the possibility that the timing cover might be a source, since it had to be removed. The old gasket was not damaged when I took the cover off, and was replaced with a new one. Both surfaces were clean at re assembly. Still a puzzle on how oil got into the coolant system. I am flushing the radiator again today, and doing another "leak down" test.
 

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I installed a Melling cam and lifter set in May, the cam was properly "broken in", and the motor ran strong for a few days, but developed a soft cam lobe. At that time, there was no oil present in the cooling system. A few weeks ago I installed a "Howards" cam and lifter set, broke in the motor, and it ran strong. Except I discovered the oil in coolant now.
I thought about the possibility that the timing cover might be a source, since it had to be removed.
Given that history, my vote is for the timing cover to be the most likely source of the problem. If the coolant passages that are on the "back side" of the cover are leaking, or if the cover itself is cracked anywhere around those passages or in the cavity for the water pump, that will allow coolant into the oil.

When "something changes" (in this case the fact that you now have a leak), always suspect everything/anything that got changed or touched between the time when the problem wasn't present and when it appeared.

Bear
 

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I agree that the cover is the next thing to check. If you have a smoke tester or can get access to one, you can connect it to the radiator and look to see where the smoke is coming out and save hours of guesswork. In the last 10 years of my job, I couldn't believe how well these detectors worked for finding ANY type of leak.
 

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Discussion Starter · #26 ·
Thanks for your input everyone. I ran the leak test again, still could watch the needle slowly move off 14bs. I decided to throw in the towel and I will remove the heads to see if I can be a bad head gasket. To answer BearGFR, there is no antifreeze in the oil pan, only oil in the cooling system. I have attached photos of the sludge I scooped out today, before the final leak down test. Also, today I was able to see bubbling in the water through the neck of the radiator, while the motor was running. Phil Powder Ingredient Flour Whole-wheat flour Cuisine
 

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Thanks for your input everyone. I ran the leak test again, still could watch the needle slowly move off 14bs. I decided to throw in the towel and I will remove the heads to see if I can be a bad head gasket. To answer BearGFR, there is no antifreeze in the oil pan, only oil in the cooling system. I have attached photos of the sludge I scooped out today, before the final leak down test. Also, today I was able to see bubbling in the water through the neck of the radiator, while the motor was running. Phil View attachment 155932

You have any enemies? That does not look like oil foam. It looks more like someone slipped some Tide detergent into the coolant. Oil foam is gonna be brown and it'll certainly feel "oily."

If that is oil, then my money is on a cracked block or head. There is no oil passage that would pass oil into the coolant unless there was a crack. I had a '97 Toyota pushing oil into the coolant. Shop said the engine was cracked. I did not agree and told them to pull the head and let's have a look and I would pay for it. They said they did not want to take my money as they were sure it was a cracked block. I insisted. Yep, right next to a coolant hole in the block/head was this small oil supply hole that went to the head. That little smidgeon of gasket material had failed and the higher pressure of the oil pump was pushing oil into the coolant passage. They all said they would have bet money on a cracked block with all their experiences tearing apart cars and that was the first time they had ever seen that. Put it all back together and ran the car another 40K miles before selling it with 271,000 miles.

If you had an early pre-1965 engine that still used rocker arm stud oiling through the block, then I might agree that it is a head gasket. But since it is not, I am baffled as to where oil could enter the coolant through the head gasket - look at the oiling diagram.

I would NOT tear that engine down just yet. Take a sample and have it sent out and analyzed. Find a local truck rental shop or a shop that works on/rebuilds big rigs and get one of the analysis kits and have them send it out. Might be $25-30.00, or it was anyway. That will 100% identify what you have going on. Would be a shame if some prankster was screwing with you and that's soap powder or who knows what.

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