WTF overheating again
 

My last motor cracked a head or the block, we never actually found out. Just put in a new motor (rebuilt) from Gearhead. All is fine, but now it is running super hot again, with less than 30-40 miles on it. I have replaced the thermostat, water pump and the f-ing motor. The radiator was replaced by the previous owner and is an aluminum tank with plastic ends.

What the hell else could be my problem, I just want to get in the dirt.

Any ideas would be greatly appreciated. I was on NAXJA but now it seams to be out of service all the time, so I found this site and hope it works out well.

Thanks

Some items to check if you have not already.
Inlet to ac condenser for debris or anything that can restrict airflow
Electric fan if it is coming on?
Is sensor good?
With everything else new I would check those.

Thanks
 

I will take a look at those items and let you know what happens.

Water Pump Rotation
 

Another item that has me concerned is the water pump, I know this is not the most accurate information, BUT, i went to Summit Racings site last night just to see what another water pump might cost and found this.

If I select my vehicle but without telling them I have the Sport model, it recommends water pumps with Counterclockwise rotation, when I selected the Sport model from the tree it changes it to Clockwise. I did contact the people at FlowKooler and they recommended the Counterclockwise rotation unit, however, I ended up buying the Hesco HF58-455, which I don't even know what direction it pumps, but it seems to be listed on a number of Jeep models on their site. Anyone know the correct rotation?

I agree with abovetimberline. Let it heat up and watch for the fan to turn on. If it doesnt, start there.

Make shure the coolent is full and purged. With the radiator cap off, start the jeep and fill coolent as needed till t-stat opens up. top off, and cap it.
Do this with the heat on! so the valve lets water thru the heater core.

Other things to think about are like the way the drivebelt is being routed.
Weather or not the drivebelt is slipping.
And make shure its got the right water pump in it. I know with chevy, and I am not shure about jeep, but they made watter pumps for spinning in both directions, and if you had the wrong one it would overheat. Just a thought.

I will bet on the pump being the problem!

Took a while to get my last post typed.

Now looking at the pulley from the front of the vehicle, the rotation should be counterclockwise.
Crankshaft, alternator, AC and PS pump are clockwise.
Water pump, fan and tension pulleys are counterclockwise.
Basically all the items that are driven by the multi-v side of the belt have the same rotation of the crankshaft, all those that are driven by the flat side rotate in the opposite direction.

Apart from the electric fan, is the viscous clutch of the main fan good? Does it turn strong and loud?
How many miles after the radiator change?

The radiator with he plastic ends might be the problem

Thanks for the help. Last night I changed the thermostat back to a Mopar one just in case the aftermarket model was fowled. Started her up and let it idle for a few then went and checked the gauge and watched as it slowly crept up and straight for the red. I am going to check the water pump rotation now to see if it is correct and calling Hesco to see what direction the pump they sold me is turning, their site doesn't list the direction.

Of course minutes later, I got a hold of the tech from Hesco and he said it is CC rotation and added that all of them are CC rotation unless it is a V belt conversion or older motor. Anyway, he also added something new that I never heard of, the catalytic converter. I told him my last motor died and the new one is still getting hot, he said if any coolant made its way to the cat it would nearly be plugged and may need replacement. It will cause large amounts of back pressure and heat the engine. Gonna check this as well. I am also going to try and replace the heat sensors just in case.

Thanks for the help.

Did you check your e fan when it crept up. It is a one speed fan and you should here it even from inside the vehicle.

The e-fan works fine. Replaced the cat and now replacing the coolant temp sensor as well. We'll see what happens.
Thanks

i hate cats........ they make engines do retarded things! :cursing:

Water pumps are pretty straight forward. If they leak at the weep hole- bearings and seals shot replace. I've haven't seen a broken shaft on a water pump but have seen some eroded impellars but not enough to cause a cooling problem. They are just centrifugal pumps and just sling coolant. You might want to pick up an infrared temp gun. You can shoot the thermostat housing, inlet and outlet of the radiator to see if there is a temp drop across the radiator and verify your gauge accuracy. Check your fan clutch too. I'm not too far from ya so I maybe able to come down and check it out. How much was the motor if I may ask? I turn wrenches for a living but I'm no Jeep expert.

-Charles

OK, so here is the very long run down of how I got here and what we replaced along the way.

The very first day my lift was completed in April of 2009, we went with the family and one of my daughters friends to Saddleback for some simple fire road fun. On the way the Jeep overheated severely while on the freeway at 65 mph.

Went to Jeep Care Center in Huntington Beach and replaced the water pump with a Hesco unit, new thermostat and thermostat housing from Hesco as well. The radiator was new and replaced by the previous owner. New fan and fan clutch.

Took it to work and it overheated on the freeway again.

Back to Jeep Care Center. They pulled the head and when they loosened the last bolt the head literally popped off the block since it was totally warped. They assume that either the head or the block were cracked and I was out of cash. So it sat in the parking lot of my work for almost 10 months.

Bought a reman ATK motor from Gearhead Engines. Installed the motor and started it up and it began to overheat, WTF? I was feeling a little cursed and started looking for Jeep shaped voodoo dolls.

Then I had had enough and began spending like an idiot, new fan clutch again, new thermostat again, new catalytic converter and it was still running a little warm at around 215-220* with some spikes into the 235-240 range when sitting at idle. BTW, the catalytic converter idea came from the tech at Hesco, I called and asked about the pump rotation and explained my situation and he offered many possibilities including the one I had never heard of, the Cat. He explained that if coolant got into the exhaust it could plug up the cat and cause too much back pressure and heat the motor. I checked the existing cat and could see some sort of thick black residual drip coming from the joint directly before the cat. So I replaced it for around $200, the Jeep was noticeably more responsive but the heat issue was still there. Then we replaced both temperature sensors and adjusted the timing and now it runs fine, steady between 210-220*.

Now that I have spent more money on the motor and parts than I paid for the stock Jeep, I better get some good use out of it. The way I see it is this, I could have bought another used Cherokee and swapped my lift and stuff over but then I might be in the same situation. At least now I know that most of the engine compartment is new and the motor has a 3 year warranty, kinda like a new car, but not quite of course.

Thanks to everyone for their help and suggestions and I hope to see some of you out on the trails soon.

Brian