Chick-N-Picker

89 Jeep Cherokee 4.0 auto 4x4

First I want to thank everyone on here all of you really helped. I changed my fuel pump and boom it started right up but now I have a couple other simple problems, I think and hope.

My problems are:

1. The electric cooling fan is not kicking on and if I sit for much time at all my temp needle starts to go up and I accidental ran it hot the very first drive. I'm an idiot but I don't think I hurt anything, I hope. It was running good after I cooled it down and test drove it and didn't stop and give it long enough for the temperature to climb.

2. The heat is only blowing luke warm, not hot. So I know to flush the core because one: it will not cost anything. Then check thermostat after that.

3. My A/C is not working. How to check if clutch is kicking on?

4. My dash lights are not working. What could this be?

5. My fifth problem is my fuel hand is no longer working since new pump but it was before so I think the float is stuck or something and I hope when I put some more gas in it starts working if not I got to fix that crap too but it's the least important right now.

When I was trying to get this thing to run I changed the relays all around. I know the fuel pump is working so irs either correct or its the a/c clutch. the others may be wrong and can that contribute to any of the above problems?So how do identify which is which? I know where they go from this chart I just can't tell from looking at them. Is there a number or something? Or must I mark them and get a piece of paper and start going one by one?





So any advice on these problems is greatly appreciated.

rdr8887

1. have you checked your coolant level? Make sure it's filled adequately. Then apply 12v to the fan and see if it spins. You'll know quickly if fan works. Someone else will need to comment on whether or not this fan is controlled via thermostat.

2. Flush the core and try again. Report back.

3. You'll know by standing in front of the motor. The compressor has a clutch on the front of it that will spin when engaged. It's separate from the pully. You can also hear it when in operation. This could also tie back to your electric fan. Electric fan should be on when AC is selected. Could simply need a recharge....I don't know how to troubleshoot that.

This is a lot of questions in one thread. Might be hard to follow answers

Chick-N-Picker

Thank you and I'm sorry for so many questions but I tried to keep it simple with 1. 2. 3. system. I didn't want to start so many threads I thought it might be aggravating to y'all to have so many threads by me stacking up.

I guess my biggest question is can those four relays being in the wrong spots cause any of these symptoms and if so how can tell the relays apart and get them into the correct position. They look the same. Is it a test or something?

StuckBuck

When you do a flush I would highly recommend using a flushing agent. I completely redid my cooling system and I flushed and flushed with water. Then I used a flushing agent and flushed once and it cleaned out everything. Turns out my system was basically held together by stop leak and when I used a flushing agent it pulled the stop leak out of my radiator, water pump, and the little splitter fitting that the heater core runs to. Basically a $10 bottle of fluid uncovered about $150 worth of band-aided problems. Now my system runs fantastic!

extrashaky

If your temperature is fine while moving but climbs when you sit at idle, that's the classic symptom of a bad viscous fan clutch. The fan clutch tests you see on here sometimes where you spin the fan are not reliable. If that's what it's doing, I would go ahead and replace it.

4WD4EVER

Glad to know you know it was the fuel pump. Now how about we deal with one thing at a time since you've got other issues. Get your cooling system functioning first to avoid unnecessary damage. Flush it.

If possible, I recommend installing an OEM thermostat. If you can't do that for some reason, it's understood. Let's see what happens after that to your temps. If it has been sitting for an extended period and/or neglected, it probably has nasty crud in it.

Just FYI, I believe there were 2 different fuel tanks used in 4.0l's then. A 13.5 gallon or a 20.2 gallon. It's possible that the gauge is not reading correctly because you may have the incorrect pump. If I'm incorrect, hopefully someone else will chime in.

Keep us posted.

Chick-N-Picker

On problem 1. Cooling fan
Which I find most important since it has to do with over-heating.

I ran a test hopefully correct. I got out my meter and check the battery with the switch turned to on but not running. It was putting out 12.7 volts

I then checked the fan connector (the one coming from under) with the key on and it had 0.16 volts. I then turned on the a/c even though it don't work and it still tested 0.16. Does mean anything? Did I do it right?

Here is the plug connector I tested:

4WD4EVER

This should get you going:

http://www.lunghd.com/Tech_Articles/..._Diagnosis.htm

Btw, I believe you're going to have to get the fan clutch issue resolved before the electric fan will function as designed. The electric fan is designed to kick on when a/c is on.

Here's a way to test the fan clutch safely:

http://www.jeep4x4center.com/knowled...-diagnosis.htm

Chick-N-Picker

Okay I will give that a check but I do t think there is nothing wrong with that but heck I don't know. It's worth checking.

I thought it was the electric fan because I only start to run hot if I sit with it running or drive at very low speeds. As long as I keep air blowing through the grill it runs 210 or less

4WD4EVER

Flush old coolant, replace thermo w/ OEM if possible (it has a better design than aftermarket), check fan clutch and then go from there. Keep it logical.

Chick-N-Picker

I will do all these because it needs a good flushing any way I suppose. And tstat is not a big deal. I'll also check the fan clutch.

But how will that fix my electric cooling fan? I'll still run hot unless I keep it in the wind.

I'm going to flush radiator today.

Bobolink

I don't notice that anyone has answered your question about the relays.....so I will. It makes no difference on your '89. On the Renix, all four relays are the same and are interchangeable. Your diagram is correct ... A/C clutch relay in front, O2 sensor heater relay at the rear.

Chick-N-Picker

Here is how I was going to flush the radiator.

Go out and drain all the water in from the plug.

Put plug back on. Full it water.

Crank engine. Go unplug drain. And continue to pour water in the as it flows out.

I was going to do this for about 20-30 minutes. Is that a good way to flush it?

extrashaky

FYI, that test doesn't always work. Mine passed the spin test just fine, yet my fan clutch was bad.

The only truly reliable way to test the fan clutch is to remove it, move the spring 180° to lock the clutch and reinstall it to see if it fixes the problem. By the time you do that, you might as well just replace it while you have it off.

4WD4EVER

It won't "fix" it but if the fan clutch is not functioning correctly it can throw off the timing on your electric fan when you use the a/c.

Who knows, it may be the thermal switch on your radiator that's causing the electric fan not to work properly but you've got to make sure the rest of these components is working correctly. They all work together as a system.