W7AMF

ill keep this brief:

95 cherokee
4.0l 4x4 auto

i just bought this jeep a week ago. it runs and drives great and has almost no rust on it.

I went to the junkyard and picked up a gauge cluster with the appropriate gauges… the idiot light cluster suuucks.

i installed the proper cluster and prier senders.

the jeep is running hot according to the gauge! the idiot light in the old cluster never came on and it has a fully functioning bulb in it (i tested it with a 12v battery)

the PO put a water pump on it. today i installed a new thermostat (tested in a pot of water on the stove, works great. I also drilled two 1/8 in. holes in the rim as I've always done before), new stat housing, and peak flush kit. the PO put in some kind of stop leak. I flushed it all out. filled, burped, filled burped ect. several times. upper hose gets very hot, lower hose barely gets warm.

i back flitted the radiator to make sure it isn't plugged and it flushed perfectly. same with the heater core.

I have good heat. The electric fan doesn't kick on ever but the gauge still reads on the bottom of the red, or in the red.

all indicators seem that cool an is flowing, but the lower hose is cool.

tomorrow i plan to take the tstat out all together while i figure this out, and install a new water pump. (the pump in there is def new and shiny, that the PO installed)

it doesn't boil over or anything.

anyone else have any other suggestion?

Larry's XJ

Leave stat alone.

Considered "new" to you sender is junk?

100% sure rad isn't plugged?

Either get IR temp tester or old school gage you put in rad. Looks like cooking thermometer.

HEAP of JEEP

Agreed. At this point, I would say it looks like a bad sending unit or perhaps a bad gauge. You need to verify the actual running temp before throwing anymore parts at it.

W7AMF

my only problem with that is, my upper hose is screaming hot and my lower is cool to the touch.

id like to ad that it heats up within just a couple/few minutes too.

its acting like there is air in the system and/or its not circulating well enough.

Crazy 8s

It sounds like the tstat is not opening. It was not possible for me to put mine in backwards, as I tried just to see...but yours may be slightly different.

Maybe this is a ridiculous suggestion, but it seems like you've already covered the bases.

gunmetal_nightrider

Isn't that the point? One is hot and one is cold.....coolant coming to the radiator will be hot as hell. Thats what the whole system is for....

W7AMF

yes sir, same here. mine won't fit backwards.

i was under the impression the the lower hose was the hot side (drivers side) and the upper hose is the cold side (passenger side) please someone correct me if I'm wrong so i can stop stressing it! haha.

dmill89

You've got that reversed, the lower hose (driver's side) is the feed to the water-pump (cold) and the passenger side is the upper hose (passenger side) is the outlet from the engine (hot).

Crazy 8s

It is hard to imagine a new pump not pumping at all. Maybe less than it should, but it is such a simple device that it should pump atleast some water through the system.

You will probably need to take it all apart to see if there is some sort of blockage in the rad or the block or the hoses. Did a shop rag get left in there somehow? A bolt in the pump housing?

On a positive note, it is easier to work on the cooling system of the XJ than it is for a lot of other cars....

jmrec100

Do you have an electric secondary fan? If so, does it work?

Fred/N0AZZ

After all you have replaced I would replace the radiator also a good idea an any car this old and one that had a stop leak even more. A new one from AutoZone is only a $100 with a lifetime warranty then you have an all new cooling system.


I would check the temp with an IR Heat gun to be sure the gauge is correct.

SteveMongr

Once stop leak had clogged the small passages in radiator, it is difficult to flush out and will reduce flow. I would replace it.
But verify temps with an infra red temp gun first!

W7AMF

yes and yes. it doesn't come on unless i unplug the sender on the tstat housing. but it does come on.

where do i point the IR temp gun? at the radiator? or tstat housing?

the radiator looks like its newish as well. id hate to have to replace it… not to mention its a pain in the ****.

im picking up parts and a better gauge today! and a new temp gauge sender in case mine is defective.

stand by….

cpefy3

I also would check your temperature with an IR thermometer at the Thermostat housing. And I maybe incorrect, but I think if you remove the radiator cap (when the engine is cold) and squeeze the lower radiator hose you should see coolant rise out of the radiator neck. I know this is the case when squeezing the upper radiator hose (to help ensure the thermostat isn't stuck open) and I would assume this could help to ensure that your radiator isn't clogged entirely. I had an issue where my radiator was partially clogged and it would idle fine but once you were on the highway for a little while it would overheat.

tlang

Come on OP You sound like a smart guy. You got this.

What are you fixing exactly? The temp? Well first issue is what is that exactly? YOU NEED A TEMP GUN first and foremost. Point the IR gun at everything and see what the system is actually doing.

My other thought would be what temp t-stat did you get?

I am a bit concerned that you say it happens pretty quickly. This seems like a blockage like stated earlier, either Rad or block.