Just thought I would bounce this off ya'll. Father in law has a mid 90's straight 6 in a Jeep Cherokee. The water pump lost the front bearing and took a ****. After changing the water pump, it heats up after driving 3-4 miles. Keep in mind, everything was fine until the pump went out. It has an engine driven fan as well as an elec. backup. Here's a list of things he has tried. New water pump New T-stat New sending unit for the gauge New sending unit for the elec fans BTW, this is a factory new pump, not overhauled. Coolant circulates and the car runs cool as along as it is sitting idle. I am out of town so I am trying to troubleshoot this over the phone. Thanks Root
did he get all the air out of the system? might be a bleeder screw somewhere on there he hasn't noticed.
is it a backwards rotation application,(water pump),and possibly have a standard rotation one,or vice-versa?
what yorg and stealth said .....AND make SURE there is a SPRING in the lower hose ......if not---the pump will **** the hose CLOSED at speed....seen it several times.... Jersey Skip
Thanks guys. I thought about the rotation issue but since it was a factory pump I figured they should know......The lower hose is interesting though........I'll hafta see if he had changed them recently or if he was having problems with it leaking in the past.
I've got 2 jeeps with that 252 L6 in them and I've been through this same problem twice. The big clue is that the electric fan never comes on. The right side (p***enger side)of the radiator will be scalding hot but the left side where the fan thermostat is located never gets more than lukewarm. The lower most tubes are probably clogged. Change the radiator and all will be good.
It could also be air. Disconnect the top hose from the pump and fill the radiator through the hose. Then reconnect it, start the engine and top off through the overflow tank
Root- I had a '97 Cherokee and the water pump took a dump on me also.... Had to do a swap in Bowie Texas while on a road trip.... I have never busted my knuckles up so bad in all my life!!! I hate new ****! Anyway.... I would check the lower hose.... I forgot to put the spring back in mine and as I was turning the final bolts, it fell on me when I was underneath.... Hit me on the head and reminded me to put it in.... As I was putting it in I noticed how flexible the hose was and imagined that without it the hose would **** itself shut.... I would check that first as well.... Does it overheat after running at idle.. or only when driven? (ok.. I just re-read your post.... it has to be the hose collapsing) HC
<font color="green">Definitely check the lower hose spring thing. I had a problem with that a while back and it was a ***** to figure out. LOVE YOU< RASHY </font>
Also check the spark plug leads, had this happen on my mom's car. Drivin down the hiway it would just over heat, could never figure it out. Then it happened at nite, you could see the cracked lead arcing on the head. Just something else to look out for.
I am not familiar with jeeps and certainly not anything from the 90's, but could it have been possible to have put the fan on backwards? In other words instead of pulling air through the radiator it may be pushing air against the opposite fan resulting in no heat disappation. In other words two air m***es coliding and not allowing for any cooling. I have no clue if that is possible to do with your particular application or not.
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