JackHass

I recently finished installing a brand new head on my 4.0. After checking, and double checking all of my work I started her up. Fired up right away, and idled very very smooth. I checked for any leaks and found none. The thermostat was changed as well, with an oem one from the jeep dealer. After idling for about 10 min, I noticed the temp increasing, and rising up close the red zone. I shut the engine off, and began checking things. I noticed that both upper and lower radiator hoses were cool. I pulled the hose to the thermostat housing, and saw that there was not even a trace of coolant in there. After an hour or so, I fired it up again, and the idle was just as before, very very smooth. My question is, do you think I damaged my head and/or gasket? And would the radiator or water pump be the culprit?

Thanks in advance!
JH

TXstiGuy

Sounds like the water pump.

85on32+4

x2

Turbo X_J

Is the thermostat installed correctly (actuator towards the engine)? Does the thermostat have a jiggle pin or did you drill a hole to allow trapped air to bleed out?

JackHass

Thermostat was put in correctly, by myself. It has the jiggle pin in it and is oem from the dealer. Whats the procedure to determine if the head gasket is blown? I'm worried about my new head and gasket being affected by the overheat.

Firestorm500

The head gasket may have been installed backwards or upside down, blocking cooling passages/circulation.

JackHass

gasket was put in with the word "top" on top

Firestorm500

That's a relief.

Did the gasket say "front" on it anywhere?

JackHass

can't recall.....it was the felpro sd version.

85on32+4

felpro-nice choice lol
your oil look like soup?
coolant a weird color?
temp change while just trying to start it?

JackHass

Felpro was the gasket that was available lol. Coolant color looks normal. Started it up today for about 5 min, and watched the temp carefully. I looked in the radiator cap and saw no bubbles, so I think the head and gasket are ok. I had the upper hose (one to the thermostat) off, and noticed no coolant flowing when the temp rose. The electric fan didn't kick on either (yes its plugged in) I shut it off when the temp was about 240.

My theory is that the radiator is blocked up, and or the water pump is busted. The water pump was changed about 7 months ago though.

What do you guys think?

Thanks

85on32+4

yea but its unusual to have your coolant system plugged....
tell you what, just take out your thermostat and and run it without one....just to see if your temp doesnt rise( it shouldnt) {do NOT leave it like this in winter, in summer it is ok to run without a thermostat and just recconect the housing}
this should tell you something... let me know

tablerockfshr

What was the original problem to warrant a new head gasket?

Turbo X_J

The only way a water pump will break is the impeller will become disconnected from the shaft. This is very rare, usually the shaft seal goes bad causing a coolant leak. Did this overheating occur shortly after the installation of the "new" water pump. If so check to make sure it's not a reverse rotation water pump.

JackHass

Update....

Just did a complete cooling system flush, and then let the jeep idle for about 50 minutes. The temp held steady at 203-207. So I guess that was the fix. I'll probably replace the radiator soon as a precaution as I believe it is the original. Thanks guys for all your inputs, and tips! It's very much appreciated!