Blown head gasket or something else?
I recently noticed a gunky, chocolate looking substance when I removed my
oil fill cap. It was definitely moisture mixed with oil. Also, my coolant has
gotten a little low on a couple of occasions within the last month. I first
noticed it because the heater was not blowing warm air then I noticed the
temp gauge moving close to 200 degrees (mine usually stays much lower
than that). Yesterday I noticed a small oil leak coming from one of the valve
cover grommets on the passenger side. I replaced the valve cover gasket
and all four grommets. Everything appeared normal. I then changed the
gasket and grommets on the driver's side. The same gunky, chocolate
mess was inside the valve cover. This 2000 Suburban has 435K miles on it;
been a GREAT car. It has always gone through at least one quart of oil
every 5K miles and is still doing that. It has white smoke from the exhaust
right after its started but it clears up after its completely warm. Is this an
indication of a head gasket beginning to go bad or could it be something
Well if it is a head gasket, I don't think you would want to fix it with 435K on it, that is just amazing. But, the white smoke is an indication of coolant getting into the cylinder and burning off. You should be able to smell a sweet smell from the exhaust. The moister under the oil filler cap is normal, just replace the PCV valve and breather element for proper ventilation of the crank case. You may want to put some sort of head gasket sealer in the coolant, but you need to be careful in what you put in as some stuff can plug the heater core. Just ask what is best at your local parts store.
A new crate engine from Chevy would get you back on the road. Maybe the next one will get you to a million miles!
Hey Rowefast, I would definitely not change the head gasket with that many miles. I figure I'm already on borrowed time as it is. I considered using a head/head gasket sealant but I've never tried that before. I'll change the PCV valve and air filter and see what happens. I changed the oil yesterday and it appears to be free of water and no "gunky" stuff came out of the pan. The truck runs great. My only real concern is the small amount of water/coolant that is going somewhere. Nothing leaking underneath when parked. Thanks!
I had a head gasket go on me on a 88 Ford ranger V6. Oil was leaking into the oil. Lots of miles, didn't want to pull the head also. So I put some stuff in, can't remember what kind, for sealing head gaskets. It worked just fine. I drove it every day for the next 3 years with no problems until I sold it. But Just a thought, Have you looked at the Water Pump? I have seen them leak and steam out the weep hole and seal back up. There should be a visible stain under the weep hole.
I just changed the water pump a couple days after Thanksgiving. It had started weeping and got a little warm, not HOT. A little over 200 degrees. That could have possibly caused a head gasket with 435K miles on it to stress out a little. Thanks again!
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