Well if that wasn't the most frustrating thing that's happened today....

Spent a while typing up a nice description of my problem and when I went to post it, said I wasn't logged in and I lost it all. So here I go, attempt #2, less descriptive....

94 4x4 p/u 22re with around 135,000 miles

Runs great, fires right up, sprays coolant from the radiator cap when the engine is shut off. New radiator cap didn't fix the problem. There seems to be a lot of pressure in the radiator (more than usual) after driving. I'm thinking head gasket. However, it is not presenting other usual symptoms. No coolant in oil, no smoke, and no water out the tail pipe. And the only water I lose comes from the cap.

Any ideas? Any further questions, let me know and I'll explain more in detail. It's late, and I'm tired of typing.

 

sounds like it might be a bad water pump, is the gauge hotter then normal or anything?

 

Temp never gets higher than normal.

Like I said, it runs and drives great. I wouldn't suspect anything was wrong if it weren't for the coolant covered engine compartment.

 

How old is the radiator itself?

 

Radiator was replaced in February 2005; The whole system was flushed in January 2008

 

Less than 30,000 miles ago as I had the 100,000 mile front diff maintenance done at the same time.

 

Anyone???

 

Have you checked your plugs? You should do a leak down test of the cooling system. Can tell you if you have a bad HG.

 

First thing I did was replace the cap. There was a rip in the gasket. Thought I had it fixed, then I drove it to work and had the same problem.

 

Pulled the plugs... 1 and 2 had a little corrosion on them, 3 and 4 were clean. I haven't had to add any coolant since the flush 2 years ago. (until now)

 

I'm leaning toward HG, but I want to be sure before I tow it up to CO Springs to work on it. But I'm not getting any of the catastrophic failure symptoms.

 

Is your radiator cap seal leaking, or is the relief valve in the cap opening and releasing coolent into the resevoir? Is the lip on the opening of your radiator damaged and not allowing the cap to seal? If you are reaching the pressure limit of the cap ,it should open and release coolent into your reservoir, not spew from the seal no matter how much pressure is in the radiator. You can buy a block checker kit for about $50 that will tell you if you have combustion gases in your coolent.

 

It sprays (high pressure instant 1 gallon release) from the seal on the cap. No extra coolant goes into the reservoir. There's no pressure in the rad (well there is, but not enough to be leaking) until the engine is turned off. Running is fine, but as soon as the engine cranks over the last time it over pressurizes.

 

When you shut an engine off your coolent temp goes up( coolent is no longer moving through the engine / radiator) and soaks up any heat left in the engine( thats why its happening when you shut off the engine).
But you have a sealing problem with your cap. The releif valve should open long before the seal leaks. So even if you overheat the valve will open first and let the coolent into your reservoir. Check to make sure that you are not overheating, dont always trust your temp gauge ( buy an IR temp gun , it will tell you what your temps really are).

 

Is the tube feeding the reservoir blocked or cracked?

 

The tube feeding the reservoir is in good condition free of any cracks/holes/blockages.

I'm thinking more of a cracked head.

Any way I can narrow it down to either HG or head???

 

You need to do a pressure test on the cooling system to see if:

A. It holds pressure
B. You notice if any coolant is leaking out anywhere.

That will tell you if it is the radiator, water pump or head gasket.

Also get a tester for your coolant that shows if there are hydrocarbons in the coolant.

Both testers should be available at a parts store and should be available for rent.

Then come back and let us know what you found and we can go from there.

 

The last thing I want to do is order the HG set from Engnbldr only to find out I need a $350 head.

I know it's either or. I'm getting bubbles in the radiator but no other symptoms of HG. This all started a few days after it was in the -20s so my cousin suggested it may be a cracked head.

 

What the temperature outside there when its doing this? colder than 10?

Mine was going sort of the same thing. See if this helps at all:

https://www.yotatech.com/forums/f116...7-22re-225594/

 

When I noticed it having issues the temp had warmed back up to mid 30s

It drove fine during all of the cold, then I was off work and it sat a few days and that's when it started having problems.