Blown Head Gasket?

Hi. I have a '92 Explorer with the 4.0 V6 EFI engine (pushrod type). It has 280K miles on it. When I first start it up I get a lot of white smoke from the tailpipe and it runs rough. After a while the smoke gets to where it's not really noticeable and the engine runs smoother. Recently the radiator burst and lost all it's coolant. I started the engine and ran it briefly with the low coolant level and there was no white smoke and it ran smoothly. I could find no signs of water in the oil. I drained about a quart from the engine into a clean bottle and checked for condensation on the dipstick and fill cap. The oil looks normal and not foamy or frothy etc.

My question is if it has a blown head gasket, cracked head, or cracked block would there definately be water/coolant in the crankcase or could it have one of these conditions and NOT have oil in the crankcase? It seems to me that coolant is getting into the top of the cylinder and causing the white smoke and rough running. If I do a compression test should it read low on one or two cylinders and would this be conclusive, or with an engine this old would it be a waste of time and money? What else could cause coolant to get into the engine? Bad intake manifold gasket?

Thanks.

Jim

Reply to
Ulysses
Loading thread data ...

about

condensation

cracked

When you lost coolant you eather warped a head or cracked it. Head gaskets do not go bad unless something happens to block or head.

Reply to
SnoMan

With nearly 300K on it and needing internal work, wouldn't be better to rebuild the engine? With that kind of milage, there could be many areas that need attention. John

Reply to
JohnR66

">

Ever seen a 3.8 Ford engine before?

CJB

Reply to
CJB

snip

"Headgaskets do not go bad unless something happens to block or head"

Yes, they do too.

Spdloader

Reply to
Spdloader

Well, no doubt there may be some beginning signs of engine wear elsewhere (just kidding) but I'm having a difficult time finding something anything else to buy right now so I'm trying to just keep this thing running a bit longer. Rebuilding an entire engine is beyond my experience and I need to do a lot of research before buying a rebuilt engine mainly because there is a huge price difference on various rebuilds and I don't yet know why. I'm hoping that the worst thing wrong with it is a head gasket but if the block is cracked then I would be wasting my time trying to replace the gasket. That's why I'm asking if there is no water in the oil are things probably not as bad as a cracked block. Is there some way I can tell before tearing it apart? I've read a lot of old posts but could not find the decisive answer.

I agree that it would be foolish not to at least do a valve job while the heads are off and once I get that far a rebuild is staring right at me but I also have to consider that the rest of the truck has 280,000 miles on it too and needs some work that may be costly so it may not be worth putting $2000 to $3000 or more into the engine. But a hundred bucks or so for some gaskets won't hurt too much and would at least get me to the used car lot ;-)

Aside from the problems I described the engine runs really well and still has quite a bit of power. The good news is that I replaced the radiator and put some Stop Leak in it and the engine is now running pretty smoothly and there is no more white smoke out the tailpipe. The Stop Leak I used said it would repair a cracked engine or blown head gasket so I guess maybe it worked, at least temporarily.

One of the problems is that with the internet there is so much information about problems with cars and trucks that it sounds like nothing is any good. My conclusion right now is that Fords are crap but they are better than anything else ;-) Is it getting hot in here? (flames are coming, I can feel it)

Reply to
Ulysses

One suggestion I have is to try some of the block and coolant system sealers. I have nursed a couple of old vehicles along for a year or more with block and head gasket sealer. You drain the coolant, add the sealer, refill with water and run for 10-15 mins at temperature. Then you let it cool, and replace the coolant.

It may or may not work for you but depending on the size of the leak it is worth a try. It's a last ditch effort but if it works, it is $10 to get you another 6 months or a year.

I would only suggest the above if you are driving a piece of crap that you don't want to fix or cannot afford to right now.

Stephen

Reply to
Stephen

Yep, when engine loose coolant and overheat the can warp headsor crack them which ease. Headgaskets do not fail unless the mateing surfaces are stress disturbed and warp or crack changing surface contact pressures on gasket.

Reply to
SnoMan

I understand the theory you're trying to express, but, to use the 3.8 as an example, sometimes head gaskets fail without overheating problems or head cracking. The part you mentioned about stress disturbing the head gasket material is, I think, valid. Remember though that when you mate an aluminum head to an iron block, the design itself causes variations of stress to the head gasket due to differing rates of expansion and heat transfer. Therefore, engine components can work as designed, the gasket can work as designed, and you can still have a failure. The same forces of physics are in play in lots of other engine applications besides the 3.8, but many others handle the stress better than the thin-walled 3.8 gaskets.

Like I said, I think your explanation is partially valid in theory and under the right conditions, but it simply doesn't hold up in application. The 3.8 is a prime example of an engine whose head gaskets are prone to failure even in the absence of what we commonly define as overheating.

CJB

Reply to
CJB

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.