1998 Ford Explorer 4.0L OHV with a blown head gasket.

A month ago when riding to the grocery store, all of a sudden the truck started running terrible and lots of smoke out the exhaust that smelled sweet.Pulled over and check the coolant and it was almost gone so i filled it up and drove a mile back to the house.When i got back to the house it was almost empty again.My oil looked like a milk shake mixture.After reading a bunch of forums i determined it was a blown head gasket. So i proceeded to take the engine apart. i got down to the heads and after taking the valves out, i noticed a crack in the valve seats on both heads. Got two used heads online with less than 65,000 miles on them and they looked good when i got them.Got new Head gasket kit and head bolts and lapped the valves and put new valve stem seals in.Replaced all gaskets,Put everythng back together and torx it down.Went to crank it up and battery was dead. i charged the battery and cranked it up.Right away it starts making a loud tapping noise that sounded like a loud sewing machine.After letting it run for about a min,i gave it some gas (rpm2000) and it went away for about 5 seconds.i let the truck run for about 8 min and the noise would come and go and there was tons of white smoke coming out the exhaust the entire 8 min.I'll record the niose when i get a chance.Anyone got any ideas of what it could be?Actual engine noisehttp://www.youtube.com/watch?v=2trjzwZhLA0

Actual engine noise

http://www.youtube.com/watch?v=2trjzwZhLA0

Welcome to this forum! I've moved your thread into the stock 95-01 section. Did you check the oil pressure? It's possible that the oil pump got ruined.

1998 ford explorer 4.0 ohv blown head gasket

The oil pressure gauge i have just reads high or low and the gauge is right in the middle.any other ideas.

either the heads you got are bad, the engine is terribly out of time (very possible if you removed the cam sync assy) or you killed the mains / cam etc when you drove it with coolant in the oil. Are there any codes? CEL? What is the oil like now?

It sounds like the lifters are full of the coolant/oil mix. It could take a while for them to quiet down. As long as you have oil pressure and keep the revs down you shouldn't hurt anything by running it. As for the smoke, keep in mind that you pumped the oil/coolant mixture through the entire exhaust system. It will take some time for it to burn off, especially from the converter.

1998 ford explorer 4.0 ohv blown head gasket

Ok, i cranked up the truck today and let it run for about 10 minutes. while it was running i noticed that one of the fuel injectors was leaking fuel.I replaced all the old O rings with new ones.what could i have done wrong to make a fuel injector with new O rings leak?

Hey, i know this is old news for you but did you ever resolve your issue? Did it turn out to be just the injector? Or was it something else? I replaced the head gasket on my 97 and have the same issue, lawn mower sounds and white exhaust.

GenericPerson said:

Hey, i know this is old news for you but did you ever resolve your issue? Did it turn out to be just the injector? Or was it something else? I replaced the head gasket on my 97 and have the same issue, lawn mower sounds and white exhaust.

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Hi GenericPerson , some times on some engine you need to prime the lifters if not they get air and not do its job because they have air and since they are oil pressure if air its in it well you get noise and can damage them or something else , anyone correct me if I'm wrong