If an engine suddenly seems to have dumped a lot of oil into the coolant but very little coolant into the oil and still runs fine with no steam in exhaust, what would you figure happened? There is a slight possibility the coolant froze at some point. I though it was good but we had a few single digit fahrenheit days. As I was examining it yesterday the upper radiator hose would get warm running but not the lower one. Thermostat checked good in pan of water on stove. Water will flow from top of radiator out of the petcock and lower hose port unimpeded so seemingly no radiator blockage either. At any rate with oil in coolant but no coolant in oil would you think: a) blown head gasket b) cracked head(s) c) cracked block d) any combination thereof e) not enough information I will test some of the antifreeze later to see how good it was.
If you suspect it may have froze up, it probably did. I'll go with b & c with the probability of it being c over b. Bob
Way too little info. With automatic transmissions that have the cooler built into the radiator and with some OT stuff like 4x4 S10s that have an engine oil cooler built into the radiator tank I've seen several cases of this happening because of a bad radiator. The engine is fine but the cooler in the radiator tank is leaking oil or ATF internally into the antifreeze. If the coolant looks like chocolate milk it's oil, if it's pink it's ATF. GM 3.1 engines will sometimes do this due to a poor design of the intake gasket. We need to know year, make & model to even begin to guess.
I'm with Bob...C. Since oil pressure usually drives the oil into the lower pressured water jackets. Sure hope it is something easier. good luck.
Well dang it. To be honest it is an '85 S-10 4x4 Blazer with 2.8 V6. Bought it with a blown head gasket at 62,000 actual miles. Replaced the head gaskets and had the heads checked and milled a few thousandths. Wife's drove it about 6k miles. I just checked the antifreeze and it was good to 5 degrees F. According to my buddy, a local meteorologist, we have had some overnights that dipped down to about -2 for few hours. I would hope the antifreeze could not freeze totally solid in that kind of temp but it sounds like I'm probably wrong. What do you guys think of the lower radiator hose staying cold? Does that sound like more of a cause (pump) or symptom? ps. There is no engine oil cooler in the radiator of this one. Only trans cooler.
Alot of those chevys leak past there gaskets, especially the intake gasket. If it was tranny fluid it would look red on top of the anti-freeze, if it's oil than it will look like black oil on top or if it's alot in there milky white. Also the cold radiator lower hose, is the thermostat in the correct position, not upside down?
NHBandit said, "With automatic transmissions that have the cooler built into the radiator and with some OT stuff like 4x4 S10s that have an engine oil cooler built into the radiator tank I've seen several cases of this happening because of a bad radiator. The engine is fine but the cooler in the radiator tank is leaking oil or ATF internally into the antifreeze. If the coolant looks like chocolate milk it's oil, if it's pink it's ATF." This is the first thing I would check...also the easiest to check. Disconnect the oil lines at the radiator and connect them to each other. Change out your coolant with fresh. If it stays clear, then you've nailed the culprit. Then install an external, air cooled cooler, and hook the lines you had isolated to that. (Honestly, unless you are going to use the vehicle for extreme duty, you may not need a cooler.) Same thing happened to me... to lots of us, I'd bet. Very good info, Bandit.
Sorry, forgot this: When you disconnect the oil lines frm the radiator, also plug the connectors into the radiator. If the leak was in there, then water can leak back out from the crack where the oil was previously leaking into the water. Another reason to plug connectors into the radiator: if this test doesn't stop your problem, then the inside of this cooler (internal to the radiator) remains clean for reuse.
I m just across the river from you and the way our weather is now a days. You took a big chance at 5 above. And I m sorry to say this but that was a costly one. Winter time at very least 9 below because you never know. I hope nothing cracked. I wish spring would hurry up. I like working with my garage door open and not running torpedo heater.
to test the oil cooler cap off one inlet and apply low air pressure to other inlet and watch for bubbles. leak will show up instantly.
You may have lucked out and it only slushed up, taking out the trans cooler, which may also explain the cold radiator hose. Get it inside in a garage for a day or so it'll fully defrost & change the coolant, bypass the trans cooler and study it's habits. Bob
i'd check the radiator/oil cooler as already suggested. my dailey driver`95 S-10 has a 4.3 and and engine oil cooler built into the radiator. one day the overflow tank was TOO high and the engine was low on oil. the engine oil leaked into the radiator
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