88xj dshowtime

So m jeep gets hot if I'm sitting for to long but when I get on the gas or I'm moving the temp drops back down anyone know what it could be ?

Roler

It depends on what you mean with hot. Does it overheat?

If not, and your aux fan kicks in, consider it a normal feature. When you stop, air doesnt flow across the radiator as it does when you drive, so therefore coolant heat cant get rid as well, causing your gauge to go up. Normal cycle.
Might need to check if your aux fan comes on or not. Could be faulty, it jumps on when temp rises, usually you can hear it when stopped before light or sitting idle with warm engine. (switches on and off)

Edit: sorry, see just now you have a Renix, not sure about those having aux fans etc, maybe Renix peeps have other input in adjunct to the above.

Gee oh Dee

How old is the fan clutch? It could be bad as you dont need any fans while moving at speed, however you say it cools better when 'you get on the gas.'

If your sitting at idle, and it gets warm, if you drop it in neutral and rev does it get cooler?

If so, it cpuld be pointing to signs of a failing water pump or clogged radiator/cooling system.

You revving the motor may flow more coolant than at idle, causing a better coolong effect.

But if it only cools off when you get moving I suspect the fan clutch.

drakesword

Could be multiple issues.

First. Next time it is hotter then normal, cut the engine off and pop the hood. Try spinning the fan by hand. Does it spin easy? If yes then replace the fan clutch.

Second, Do you have an aux fan? I know they came with them but i have never had one in. If so check the fuse/relay/wiring to the fan and the sensor (driver side of radiator on end tank)

Third, Replace the thermostat and get a new gasket.

Fourth, replace the radiator if 1-3 dont help at all.


May need to make sure you dont have a bad head gasket but I have not run into that issue in the past so I dont know.

88xj dshowtime

When it's cool out it's it stays at the right temp but when I rev it she will stay at the same temp idk I saw it start doing it yesterday

drakesword

Something that I did not remember ... you see i have an 88 as well but I converted my cooling system.

Have you drained or been low on coolant recently? If so its likely you have air trapped in the system as the renix has a closed system.

RTorrez1

^^This should cover you problem.^^

Robert

88xj dshowtime

So I think I going to run my fan for my jeep on a switch . What do u think good or bad idea ?

CrawlnCoupe

jmo, but bad idea. if you forget it one time, you overheat and risk the motor. i would lean toward your system needing a flush if your clutch fan checks out. when was the last time you replaced the fluid?

88xj dshowtime

I really don't know I picked it up like a week and a half ago

cranesrule

It won't solve your overheating problem. A fan clutch probably will. Follow the advice given above, if you get your cooling up to snuff you won't need the aux fan on a switch.

stev-o

X2

caged

this is where i would start. most times it's the clutch fan when overheating at idle. this is a good way to test the clutch. but be 100% sure the key is out of the ignition before you stick your hand in there. it won't start automatically because it's not electric, but better safe than sorry.

also, it's not a good idea to wire up your electric fan to a switch cause if you loan out your jeep, they may not remember to do this, or you can simply leave it on when you park and come out to a dead battery.

go through all the listed tests to determine what is the faulty part, then replace.

88xj dshowtime

Thank u everyone

puk

I had similar issues in 30+ degrees (Celsius over here, that's high 90's i think for you guys), and replaced my radiator with an aftermarket one, got a new fan clutch, and then wired up my auxiliary fan to a switch in the cabin.

It is quite an easy mod to do, and doesn't keep running when the power is off, so it doesn't flatten your battery. You just tap into the correct wire on the front of the fusebox, and use a switch to earth it. If you have it switched off, it will still earth out and work when the thermo tells it to.

If you leave it on, no big deal. It just cools!

I use it when sitting in deer paddocks or for heavy beach-sand work, also when towing. Having the thermo turn it on at 105 degrees seems a bit like closing the barn door after the horse has bolted.

No more cooling problems since!

Puk