I checked my dipstick and found coolant in my oil. Is my engine toast?

Question

I have a 98 GMC Z71 with a 5.7 V8. I was loosing coolant last week and saw white fog from my tail pipe. I topped off with 50/50 . I drove the truck for two days when the heater didn't work again so I figured it was the coolant level again. Again I added a gallon of 50/50 to the radiator. (Be advised that after adding the coolant, I parked over fresh snow to check for leaks. None was found externally). Any way driving my truck yesterday, it began overheating bad so I stopped and opened my hood. Checking the radiator (No pressure expelled) it was again low. I pulled the truck into a local farmers house and He suggested that I check my dipstick. Sure enough there was a coffee cream substance half way up my stick. Question is:
Is this terminal? Can the oil be cleaned out and replaced? If I replaced the head gaskets, can the engine be cleaned out before replacing with new oil? Because it is coolant, does any or all the bearings need replacing?
Thanks
CJ Cook

Answer 1

Is this terminal? If it is still running, then no, it can be 'healed'.

Yes you can change the oil, but it doesn't fix the underlying problem, and would be nothing short of a waste of time and money.

The engine won't necessarily need to be cleaned out, merely drain all the oil out of it after replacing the head gaskets (and getting the heads worked if necessary), and put new oil and filter in it, and away you go. Assuming it is the head gasket(s), it would well be the intake, especially on GM.

Not necessarily, depends on how much you have been driving it, and how much you continue to drive it until you fix it. If you don't have any knocks etc, you have no idea what shape the rod bearings etc are in without tearing the engine down and looking at them.

Answer 2

This Site Might Help You.

RE:
I checked my dipstick and found coolant in my oil. Is my engine toast?
I have a 98 GMC Z71 with a 5.7 V8. I was loosing coolant last week and saw white fog from my tail pipe. I topped off with 50/50 . I drove the truck for two days when the heater didn't work again so I figured it was the coolant level again. Again I added a gallon of 50/50 to the radiator. ...

Answer 3

Coolant In Oil

Answer 4

A couple of more points: 1) Coolant should only be checked when then engine is cold. Removing the cap when hot will result in a scalded hand. Also, fluid level is higher when hot. 2) When cold, there should be about an inch of air space above the level of the coolant. DO NOT fill the tank all the way to the top.

Answer 5

The most likely cause of the problem is a blown head gasket. A cracked block or head is also possible, but not as likely. Because the oil in your engine provides corrosion protection to all the internal parts, your engine will probably be fine after you fix the head gasket. Remeber that coolant also has rust inhibitors and corrosion protection additives in it too, so it will not attack bearings or other internal parts. Most of the water is being vaporized and coming out the exhaust.

Answer 6

You may be able to tighten your intake manifold very carefully so as not to overtighten and putting even amounts of torque on the bolts. I owned a 98 Tahoe that was built with a permatexed water pump seal verses a gasket which placed the pulley away from the rest of the lines of serpentine drive and made the belt(s)(I replaced one every 25k) shimmy slightly for 107,000 miles and the vibrations loosened the intake manifold bolts causing leaking at the forward starboard corner of the manifold. This would have eventually allowed the manifold to loosen enough to create a clear path between oil and water to get the milk you describe. You might just be able to tighten those bolts and stop the leak and the mixin. If not, you may have to replace the intake manifold gasket. Could be the head gasket too, but my money is on the intake manifold gasket. Good luck.

Answer 7

Most likely since the thing is still running, it just needs some TLC. New head gasket (most likely, I had similar symptoms with an intake manifold gasket leak), coolant flush and oil flush and change. After that, some spark plugs wouldn't hurt. Then it should be fine.

Answer 8

You've driven it for some distance with the coolant in the oil. It's still running, that's a good sign, it may be salvagable with a good cleaning and new gaskets, bearings may have taken a beating that's going to be the hard part to determine - how many miles/km are you talking about and are you a leadfoot? Did the motor sound bad at all? You have stopped driving it right?

Answer 9

I would bet your engine is gone. It could be rebuilt, but I also suspect you've got a bunch of miles or haven't been paying close attention to it. Expect that rebuilding the engine will run at least $2-3,000. You may find that a low mileage used engine can be purchased for less money. White smoke from a tailpipe is almost always a blown headgasket. Parking it sooner to be repaired might have allowed you to just replace the headgasket. It wouldn't have made it a good engine, but it would have worked for a little while longer. Good luck!

Answer 10

All you need to worry about is the head gaskets or the heads themselves, drain the coolant and the oil, put a new oil filter on and refill coolant and oil after repairs and you're ready to go...