scubamark13

I need your help, I recently bought a 92 XJ Limited that has 97k on it. I have noticed that the engine temperature gets close if not into the red range when I am on the freeway and a steep grade for a long period of time. Then engine temp is normal when driving around town or on flat ground. I have replaced the radiator cap and coolant with a 50-50 mix and that didn’t help. I don’t think it is the thermostat or the fans because it runs fine around town. Do you think it could be the water pump isn’t moving enough water at higher speeds? Any ideas or suggestions would help.
Another problem I am having is the overhead computer display, when I bought the truck it worked intermittently and now it doesn’t work at all. I got a display unit from the bone yard and put it in and it doesn’t work either. All wires seem to be connected in the overhead console. Can anyone think of any other things besides the fuses that I should check?
Thanks,
Mark

scubamark13

Everyone,
I could really use some ideas here.

Thanks again,

Mark

ZINGGG

When overheating at freeway speeds, chances are your fan clutch is going out. I'd start there. Cheap and is the easiest cooling system component to do in my opinion. 10 bolts total - 2 for the fan shroud, 4 to get the fan clutch off the pulley, 4 to get the fan off the old fan clutch. Get the old fan on new fan clutch, get them back on the pulley, put fan shroud back in and you're done. It should take about 30 minutes if you take your time

scubamark13

Correct me if I am wrong the fan clutch stops working at higher speeds. I thought it just worked around town or below say 30 MPH?

ZINGGG

Hmm... I'm gunna say you are incorrect on that one. But I'm not an expert so hopefully someone who is can chime in. I remember reading about someone that had a similar issue replaced their fan clutch and it fixed the problem. I can't tell you the reasoning behind it though.

kjc

The clutch is to let the fan slip at highway speeds when it's not really needed for air flow. It might also have a temp sensing spring on it.. some do, some don't.
The temp gauges on these things aren't known for their accuracy.. so when it shows high, you should maybe check the actual temp with a better gauge.

I don't know anything about the overhead 'puter

Firestorm500

It could be the water pump vanes have corroded away, therefore not pushing enough coolant through the system at highway speed.

But it's probably in the head. That's what happened to mine even after replacing/servicing every cooling part.

The overhead temp/compass displays are getting old--20 years or so. They are getting erratic or stopping to work, sometimes temporarily or permanently.

You can still get a new one from Jeep for around $550.00 or so. Yes I'm serious.

captainwoot

Have a good look at your radiator, if it is starting to plug up your vehicle will tend to heat up under load, checking your wpump is also a good idea. As far as the overhead, you need to verify power and ground wires to the unit and go from there
good luck

scubamark13

Thanks for the help. I think I will just start with the water pump and see if that helps.
I really hope it's not the head!

Keep the rubber side down,

Mark

djb383

At hi-way speed, u shouldn't need any fan(s)as there's plenty of cooling air moving thru the rad at speed (unless air is being blocked). The XJ fan clutch is air temp/thermal activated, not rpm. There are several items besides a rad cap and coolant in the cooling system that need to be replaced as part of routine maintenance.......how long has it been since other cooling systems have been replaced/maintained?

scubamark13

I just bought the Jeep about a month ago so I have no idea. After looking at prices I think I will replace the radiator thermostat and water pump.

Hopefully that's all it is.

Thanks

djb383

Don't forget the fan clutch.....if u do, u'll be reminded +/-5 months from now. How about fan shrouds...got both?

scubamark13

Yes the fan shrouds are in place. I was thinking about getting the 3 core or row radiator. Do you recommend a specific brand or place to get it?

djb383

IIRC, the available 3 row "drop-in" rads are only about 1/4" thicker core than OE type 1 row rads. We went with a OE type 1 row from AutoZone. Any new rad will cool better than an old leaky plugged rad.

scubamark13

Ok so I replaced Everything under the hood that I can think of and it is still overheating. Can anyone think of anything else that could be wrong with it. I can't afford much more but I need a running vehicle. I am really hoping it isn't the head. Here is what I installed on Saturday.
3 row radiator from radiator barn
Hesco hi flow water pump
Hesco hi flow thermostat housing
Mr Gasket 195 tstat
upper and lower hoses
heater control valve
heater hoses
fan clutch
serpentine belt

Thanks for your help,
Mark