I need some help troubleshooting my cooling system problem. I have noticed there seems to be oil getting into my cooling system. My oil looks fine, no foaming, but is low about a quart. Not sure if a quart of oil found its way into the cooling. Any ideas where the oil could be getting in. Again there is no water in the oil only oil in the cooling. Any type of pressure test I could do ? Motor has about 2K miles and heads were reinstalled last summer. Car still runs great and does not over heat. Thanks for the help.
Man, that's a tough one. The other way around would be easy, intake gasket. The fact that a system, Oiling, that is pressureized only, in small, controlled passages, could be invading a system, Cooling, that is pressurized through out the entire engine is puzzling. You would have to believe that the oil is being drawn into the water during cool down. But where could this occur? Static oil is all in the pan. Real interested in seeing the comments, and outcome, on this one. Keep us posted and good luck.
What engine??? If its a 400-430.. I'd say head gasket.. since the oiling system is under more pressure than the cooling system, and those engines oil the rockers through the heads (not the push rods like later yrs).. that'd be my guess. More info would help. Thanks
Thanks for the response. Jeff the motor is a 69 430 and has been totaly rebuilt about 2k miles. The heads were taken off last summer so the head gaskets are fairly new and have been retorqued. I thought of the head gaskets but the oil hole in the block and water passages are pretty far apart so could a bad gasket cause this? I hope its not a crack in the block. Also last summer I ran the car at the track and for whatever reason the fan belt decided to come off during a pass and the motor puked on the return road. I immediately reinstalled the belt and the motor temp came back down quickly. Ran the car several other times since without any problems.
I've heard somewhere that the 430 heads are prone to cracking. I can't say what it could be, but a bad gasket can cause anything...lol. When you had it rebuilt, did you have the heads resurfaced??? block milled?? I don't know if Iron heads are prone to warping, but with being overheated.. I would've had them checked. Really, there are only a couple of ways oil can get into the coolant... One is through the head gasket... other is from a cracked passage somewhere in the head or block. I don't know of any other places where the oil comes anywhere near coolant.... If it was a cracked block or head, you'd think that coolant would leak into the oil too... after shutdown the oil pressure drops to none while it takes awhile for the coolant pressure to drop. Have you pressure checked the coolant system to see if its holding pressure?? Very odd problem. I'd venture to say that a gasket might only leak in one direction... but I can't say for sure. Maybe the its a pressure related leak... Like if its over 20psi it leaks, while sealing at under that. Your coolant runs like 15psi, while the oil can get to 80... I'm reaching here... Sounds like a buick X-File...lol Good luck... I feel for ya. what a PIA
Assuming you have an automatic trans, perhaps your problem is trans fluid leaking from the tranny cooler into the radiator. :bglasses:
i have a similar problem with my 430. i had water in my oil as well though. any way it could be somewhere behind the timing cover that the problem is occuring? the head gaskets didnt seem bad to the point of leaking in my motor and i cant think of any other place where it would occur and i've never had it off so i'm not sure...
If your engine oil does not have water in it (frothy), it is most likely a broken trans cooler inthe radiator.
Thanks guys for the help. Just to make it a bit harder to figure the radiator is aluminum and does not have a trans cooler. I have a separate cooler for the trans so trans fluid is not the case. I wish I knew of a way to tell if it really is the head gasket. Its a major pain in the :moonu: to take the headers of this car/motor just to find that the gaskets were O.K. Thanks again.
Alum Rad... Are you running straight water with some kind of "wetter"??? I used red line water wetter with my alum. Rad setup and it would leave an oily residue in there.. And would do some funky things with the cap off...lol. Would look like there was oil in there but there wasn't. If your running a mix of AF & water then I 'm still stumped
