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Old 09-06-2020, 05:21 PM   #1
akart
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Coolant in oil

Put new summit 72cc heads on about 3K ago. I did not retorque the heads. I have 2-3 cups of coolant in my oil. This has been going on for a while. Just found out as I use my waste oil for fire starter. So,what are the chances that I can just retorque the heads and has it done any damage to the engine? My plan is to pull he plugs,do a compression check before and after a head retorque and do a leak down test. Any chance of this working? Or should I just go for new head gaskets and see what is in there? I put in Skip White studs on the heads. If I pull the heads I'll go w/APR bolts.
No oil in the coolant.oil looks good on the dipstick not murky. 1984 Chevy 350,could be a crate engine or a rebuild not sure but supposed to have about 30K on the engine.

Last edited by akart; 09-06-2020 at 05:38 PM. Reason: addn'l info
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Old 09-06-2020, 06:52 PM   #2
geezer#99
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Re: Coolant in oil

I’d do a leak down first.
Then pull the heads.
And inspect the cylinder walls.
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Old 09-06-2020, 07:59 PM   #3
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Re: Coolant in oil

I would blame the intake first.
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Old 09-06-2020, 08:40 PM   #4
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Re: Coolant in oil

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Originally Posted by cadillac_al View Post
I would blame the intake first.
Agreed. Especially if there was any machining to to the heads and the deck
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Old 09-07-2020, 09:26 AM   #5
Corts60
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Re: Coolant in oil

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Originally Posted by geezer#99 View Post
I’d do a leak down first.
Then pull the heads.
And inspect the cylinder walls.
x2. A proper leak down test will pin point where the problem is instead of guessing.

But first, Perform a dynamic coolant pressure test to confirm combustion gases are getting into the coolant system. If pressure doesn't shoot right up in the cooling system when you start it, then you most likely could start looking at the intake for the cause of the leak.

If pressures do shoot up, then perform a leak down test to pin point which cylinder(s) has the issue.
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Old 09-07-2020, 11:06 AM   #6
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Re: Coolant in oil

Would not do any test that requires running the motor. Sounds like you have been lucky so far. Why push it?

As mentioned already, could be as simple as a leak at an intake manifold gasket around either of the front or rear head coolant openings. Might double check the intake bolt torque, possible one or more loosened a bit. Would still plan on a new set of intake gaskets.
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Old 09-08-2020, 06:10 PM   #7
akart
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Re: Coolant in oil

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Originally Posted by Dead Parrot View Post
Would not do any test that requires running the motor. Sounds like you have been lucky so far. Why push it?

As mentioned already, could be as simple as a leak at an intake manifold gasket around either of the front or rear head coolant openings. Might double check the intake bolt torque, possible one or more loosened a bit. Would still plan on a new set of intake gaskets.
I'll check the torque first,do compression test, then a leak down test.Then I'll pull the intake manifold. What am I looking for there? Will I see coolant in the tappet galley. I am seeing some moisture on top of my intake manifold.I've done 4 of these intake changes being pretty careful. This last one was to put in a set of Summit 1532123 72cc heads. No machining done and was careful to put RTV above and below the gasket on the 4 water ports. Would rather not pull the heads if I don't have to. Mechanicing is a difficult situation in Manley Hot Springs,Alaska. Thanks
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Old 09-08-2020, 07:06 PM   #8
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Re: Coolant in oil

The only appropriate way to know if the intake manifold is leaking is to perform a coolant pressure test. If you don't want to run the engine again, then perform a static test and see if cooling system holds pressure. Other than that, you are guessing that the manifold is leaking.

A cylinder leak down test will only let you know if the head gasket is the cause of the leak.
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Old 09-08-2020, 07:53 PM   #9
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Re: Coolant in oil

If the intake is leaking on the bottom you won't see it. It does sound like akart did put his intake on correctly. Whenever I re-torqued heads they were fine and nothing got tightened. I would probably do an intake R&R and cross my fingers......unless the heads don't have a shim gasket in there. The shim gasket can't fail unless it rusts out If it's a thicker composite gasket then maybe there could be failure with the gasket.
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Old 09-08-2020, 08:28 PM   #10
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Re: Coolant in oil

I didn’t see where it was asked, but did you use sealant on the ends of the studs?
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Old 09-14-2020, 06:56 AM   #11
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Re: Coolant in oil

I never heard of a sbc blowing a head gasket. If a retorque on intake doesn't work then and I hate to say this but it sounds like a cracked cylinder. I've seen where they crack in lower cylinder from freezing.
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