Coolant in Oil
Thread Starter
Pro
Joined: Jan 2017
Posts: 650
Likes: 51
From: Beaver County PA
Coolant in Oil
I removed the valve covers of my 350 vette engine and found the dreaded milky residue inside. I pulled the dipstick and the oil level was a quart over full. I have an internal leak somewhere. The plugs seemed dry so I removed the intake and here are the pics of what the heads look like. I purposely did not wipe anything because I want to see where the leak was coming from. Can you tell where it was leaking?
right rear
right front
left rear
left front
I hope it is the intake and not a head gasket, but if I don't find anything confirming this I will pull the heads.
right rear
right front
left rear
left front
I hope it is the intake and not a head gasket, but if I don't find anything confirming this I will pull the heads.
Race Director
Joined: Oct 2008
Posts: 19,126
Likes: 1,667
From: Long Island
I like the Eldbrock gaskets better.
Everyone has their preference.
I would check the heads and intake with a good straight edge before re-assembly.
Everyone has their preference.
I would check the heads and intake with a good straight edge before re-assembly.
Last edited by BLUE1972; Feb 12, 2017 at 07:50 PM.
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
Are you sure coolant got in the oil? I don't see that milkshake crud all over the pushrods and the little I can see of the top of the heads. Was that crud all over the dipstick or was it just oil?
Thread Starter
Pro
Joined: Jan 2017
Posts: 650
Likes: 51
From: Beaver County PA
It was inside the valve covers and a little on top of the heads. That's when I pulled the dipstick and seen the level was a quart high. I drained the oil and it is milky. A new radiator was put in shortly before I got the car so the coolant looks clean. I'm hoping I found the problem before it did any damage. I guess I should just pull the engine and rebuild it since it is the original engine and I don't want to blow it up.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,170
From: Hermosa
So you got coolant in the oil but NOT oil in the coolant. And it is not overheating and pushing coolant out of the radiator and overflowing the oveflow bottle?
If so, likely not a head gasket then. The coolant in those pics looks clean.
You are probably on the right track with thinking it's an intake manifold gasket leak.
I would persue that avenue, not rebuild the engine. Bad intake sealing is common enough.
With coolant in the oil obviously some lubrication has been lost to the bearings and some damage may have been caused, but it may be fine too. You'll know soon enough via a knock or squealing if damage has been done. Just stop before it blows or siezes if you hear bad noises.
If so, likely not a head gasket then. The coolant in those pics looks clean.
You are probably on the right track with thinking it's an intake manifold gasket leak.
I would persue that avenue, not rebuild the engine. Bad intake sealing is common enough.
With coolant in the oil obviously some lubrication has been lost to the bearings and some damage may have been caused, but it may be fine too. You'll know soon enough via a knock or squealing if damage has been done. Just stop before it blows or siezes if you hear bad noises.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
Depending on how long this has gone on undetected.....I would be concerned about the coolant with the oil wiping the surfaces of the bearings out.
Maybe you caught it in time before it could really mix and become a gooey mess.
Also...I have had engines in my shop where it was really bad and there was not way to get it right. That crud in the oil passages and clinging to everything... is just a recipe for disaster.
DUB
Maybe you caught it in time before it could really mix and become a gooey mess.
Also...I have had engines in my shop where it was really bad and there was not way to get it right. That crud in the oil passages and clinging to everything... is just a recipe for disaster.
DUB
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Drifting
Joined: Aug 2009
Posts: 1,346
Likes: 160
From: new iberia la
Doubtful its just an intake manifold gasket leak..unless you see an obvious break at water passage , look at your plugs, you can usually tell the cylinder where water has been leaking. Usually its head gaskets failure .. if the engine ran long with water in the oil, your bearing surfaces and cam lobes are toast
Drifting
Joined: Jul 2011
Posts: 1,697
Likes: 139
From: Syracuse NY
That coolant looks pretty clean, so Its not mixing with the oil. How 'milky' was the oil you removed? I know guys who start their engines every few weeks during the winter and let them 'run and warm up', but all they are doing is letting condensation build up. White, chalky or milk chocolate looking oil clots in the valve covers can also be a sign of simple condensation. I may be way off base here....but its worth considering before you go tear the whole engine apart.
Burning Brakes
Joined: Oct 2003
Posts: 836
Likes: 26
From: Harrisburg Pa
That coolant looks pretty clean, so Its not mixing with the oil. How 'milky' was the oil you removed? I know guys who start their engines every few weeks during the winter and let them 'run and warm up', but all they are doing is letting condensation build up. White, chalky or milk chocolate looking oil clots in the valve covers can also be a sign of simple condensation. I may be way off base here....but its worth considering before you go tear the whole engine apart.
Also the rebuild was done to sell the car so maybe the rebuilder used cheep head gaskets or re-used the original head bolts, looking at the coolant passages the head was never Cooked out to clean it so the heads never saw a machine shop.
Dr. Detroit
Joined: Mar 2012
Posts: 10,093
Likes: 4,017
From: New Braunfels Texas
Also you show the top of the gasket at each coolant port but not the backside.....look there too.
I run sealant around the back side of the Fel-Pro gasket but not the top as it is embossed and designed to "crush".
I have used Edelbrock gaskets and they are great but not available everywhere.....they are made by Corteco.....but they need sealer on the top and backside of the coolant port......and when I say sealer...I mean a thin coat....
Buy a $60 OTC leakdown tester to see if your head gaskets are ok.....I suspect they are as previously stated the contamination is one way.
Jebby
Last edited by Jebbysan; Feb 16, 2017 at 09:58 AM.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
I would pull the heads and not only check the head gaskets but check the heads for cracks. With a new radiator installed, maybe it was overheating before it was replaced. Overheating can lead to cracked heads.
Mike
Mike
Dr. Detroit
Joined: Mar 2012
Posts: 10,093
Likes: 4,017
From: New Braunfels Texas
......I like this logic.....I hate not knowing the inside condition of my engine. I like to know things are done right as well (stuff like sealer on head bolts).....this can also tell you the condition of the valves...bore, etc......it is a big tell. For the cost of head gaskets...it is always worth it to me.....plus these areas can be detailed and painted once removed.Jebby
Thread Starter
Pro
Joined: Jan 2017
Posts: 650
Likes: 51
From: Beaver County PA
Thanks everyone for the replies and suggestions. Sorry I haven't written sooner, been very busy. Anyways, I am going to replace the intake gaskets and put in some cheap oil and run it for a short while. Then I will slightly crack open the oil drain plug so that the fluid trickles out and see if its oil or coolant. This will tell me how soon (and not if) I will rebuild the engine. I plan on doing a frame off resto this year just not sure when I will start. I do want to drive the car a little this spring. If there is still coolant in the oil I will start the tear down and pull the engine.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
Not knowing how long the engine has been running with this leak...and how bad the oil is. The babbitt can be worn off or down to it. Which means the engine is toast....or will be in time.
Just saying'
DUB
Last edited by DUB; Feb 17, 2017 at 05:41 PM.