Head gasket repair

[dirkr]

So I'm doing the head gaskets. Does anyone know if there are water passages in the intake manifold on the 3.0? If so, could that cause the 'wet spark plug' issues I was seeing?

If so, will it be evident that the intake manifold's the problem during disassembly?

OR, if I've gone as far as pulling the intake manifold, should I go ahead and do the head gaskets while I'm in here? I just hesitate to pull the heads if I don't NEED to. >: ^)

-Dirk R

175k on this engine so far. Let's see if I can make it breath again.

 

[McCormack]

On some 3.0's there is an emissions control hot water feed, but I've never heard of one of those leaking into the intake. Somebody can correct me if I'm wrong, but other than that AFAIK 3.0's don't circulate coolant through their intake manifolds.

Wet spark plugs would certainly seem to indicate a head gasket leak, but if it were me I would make doubly sure that that's what it was before I went through the hassle of changing gaskets. Have you been losing coolant since you started having the wet plug problem?

 

[MAKG]

There are ALMOST ALWAYS coolant passages in the intake manifold of V6s because that's where the thermostat is.

If the cooling system is fully assembled, you can tell the difference between a leaky head or head gasket into a cylinder, and a leaky intake gasket, with a leakdown test.

If it's not fully assembled, it's quite a lot more difficult.

 

[McCormack]

There are ALMOST ALWAYS coolant passages in the intake manifold of V6s because that's where the thermostat is.

Ach, I forgot about that, and you're absolutely right. I apologize for the error, and thanks for the correction.
But having said that, I also have never heard of a 3.0 intake manifold failing and leaking coolant into the intake passages (and I'm not saying it couldn't happen), but if I had coolant getting into my combustion chambers the first thing I would investigate would be the head gaskets.

 

[Wicked_Sludge]

with that many miles, just take the heads off, do a valve job, replace valve seals, remove carbon from the chambers, and re-assemble with new gaskets and bolts.

 

[Beef52751]

gotta agree with wicked here, the 3.0s a long running motor but why risk it, will save a lot of trouble in the future.
Beef

 

[dirkr]

Well, damn. I don't have the valve seals on hand, and I need to finish the truck. The heads are still square and they actually look good. How imperative is the valve job, do you think?

-Dirk R

 

[McCormack]

There are some guys that get close to 300,00 miles on their 3.0's, so although replacing the seals and what-not would certainly be a good idea, I wouldn't sweat it if you don't.

P.S. That's just my OPINION - if you don't replace your seals and they happen to fail, don't come looking for me with a gun or anything!