87xjDave

I just put in a new CSF 3 core radiator, water pump, hoses, thermostat and new sending unit for the electric fan for a 92+ xj 4.0L in my 87 xj. It runs great on the highway temp right around 195 degrees.
But overheats in stop and go driving.
I noticed the electric fan is not coming on when hot. I installed the new 92+ sender in the water outlet as there is no connection in the radiator on a 92+ as was originally on the 87 radiator. And just soldered the wires with extra wire to connect to the stock wire harness location.
I am wondering if the sender unit is compatible with the 87 electric fan?
Has anyone successfully completed this part of the cooling system conversion?
Or is everyone wiring the electric fan to a switch?
Also I am wondering if my clutch fan is gone bad? It seems to spin easily when hot and cold.

Gee oh Dee

Moved to Advanced Tech.

87xjDave

Sorry about putting thread in OEM section. Thank you for moving to Advanced Tech section.

Also I can jump across wire connector for sender and electric fan runs great.

How much drag should you feel on the clutch fan when hot?
It spins with the engine running, but it seems to spin easily when engine is off even with engine hot.

digger21

If the fan has no resistance after being hot than get a new one. I'd start there

cdawall

just hot wire the fan to the ignition so its always on. if the fan still wont come on might want to look into a new fan.

xjcrazy

There should noticeable resistance when spinning the clutch fan. I would change it to. I think it should only spin 3 or 4 blades when its hot.

bigjohnson619

i have had cooling problems aswell... my buddy swaped out the closed radiator for one with a cap and the new overflow tank and hasnt had a problem since.. He said it was about 300 including radiator and all the hoses

brutalxj

For my fan set up I have the stock e-fan running as it should. Then I took out the mechanical one and put a 10" pusher on the grill side of the rad. I only have the pusher on when I am off road. That being said with your clutch fan not working you still should not have an issue on the road. I would say your e-fan relay is bad. I see no need in running it to a switch and hard wiring it in. It works just fine when working properly. I would switch some of the relays around to see if it is the issue. For example switch the fan and a/c relays and see if it works. Seams like the best starting point to me.

Gee oh Dee

x2, the airflow hitting the nose should be more than enough to keep the motor cool.

87xjDave

Update, here in Texas we have been over 100 degrees for the past month. So I needed to solve the cooling fan issues, ASAP.

Solved the problem, replaced the clutch fan and now it works great, you can tell the difference in noise and load on the engine when it kicks on. My old clutch fan was never putting a load on the engine or making any noise.

Gave up on finding an electric sending unit for a 87 4.0l that will fit in the thermostat housing. And just wired a switch in the console, so I can turn on electric fan when the engine gets over 200 degrees.