Oh lordy. I hope mine doesn't come down to that. I'm nervous about having a cracked head but i have the 2002 but I'm not sure if I have a TUPY head or they used the rest of the 0331 on the 2002 before a certain date... I'm getting a lot of mixed answers. But we shall see what the pressure test reveals tonight. Fingers crossed.

 

just pull the valve cover off, itll say tupy right on the top of the head

 

Easier than that, take off the filler cap and shine a strong flashlight down the hole. You should see a "TUPY" molded into the area between the two valve springs that you can see.

http://www.jeepforum.com/forum/f11/t...31-head-977498

 

^^^^ what Dave said.. look down the oil filler cap. look for TUPY

 

Nice shot Duma! I just took a while to upload a jeep forum link.

 

I forget where I got it, somewhere on the net.. So I cant take credit.. But I will anyways,, thanks lol

 

So good news is I have the tupy head. The wierd news is that I pressure tested at 15 psi and it stayed there for about 2 minutes before loosing pressure to only 14 psi which is normal loss through the tester. This revealed no leaks. Also the oil cap had what looked like moisture so we did 2 head gasket tests. We tested for hydrocarbons in the system using a sniffer and also the dye test. We got nothing. Next step, I put the in-system dye and where ever it is leaking I'll find with a UV light. Going to run it a couple days before I look for it because its such a slow leak. I gotta find this issue the guys at advanced auto already have a joke when i come in saying here comes coolant chick and they have my stuff ready. I hope my jeep finally tells me whats up its becoming a hassle.

 

That's not enough pressure. My 2000 WJ has the original factory cap, been tested several times, and is an 18 lb cap. We tested it 16 lbs and found no leaks, but at 18, there were slight seepings from the radiator.

The normal pressure test is supposed to be 2 lbs over the rad cap setting. Most pressure testers have a collar that you put on the pump to test the cap. My cap has 206K miles on it but still blows off at 17.5 lbs.

 

Oh on alldata it said to test at 15 psi. Well see what happens with the dye. I think mine might be the radiator. Just went to look at it now and it looks like on the bottom left there is moisture.

 

The leak revealed itself... water-pump failed this morning.. would explain why i never saw coolant on the ground..

 

Hope you have good luck with her now!

 

Once you get the fan and shroud off, check the radiator closely, especially the 4 corners where to fins are welded to the tank flanges. All 4 of mine showed signs of corrosion from minor seepage leaks.

 

Yeah I plan to replace the waterpump belt, idler pulley, tensioner, and radiator. Anything else I should add to my list while I have that area open? Someone mentioned on a different thread about the waterpumps having plastic rather then metal impellers. Is this the right one from NAPA that comes with the metal impellers? https://www.napaonline.com/napa/en/p...293_0207218773

I also plan to do the Dayco belt and pulleys. Any issues with those?

 

Ask for the NAPA PREMIUM pump, then open the box and look at it. The one in that picture is plastic. The problem is that impeller spins about 1/16" away from the #1 cylinder barrel. A little wear in the bearings and it can strike the barrel and explode! My 97 ZJ had a groove in the barrel from the impeller hitting it.

 

Dayco makes quality parts. You'll be good with those.