We have a 96 Cherokee that has issues with overheating, It would get to the red line, so we'd have to turn the heater on to cool it .Hubby has replaced radiator, radiator cap, heater core, thermostat. He also took out the non functioning a/c for more air circulation, he put the correct pulley on it, when he removed the a/c.he did the work and it ran ok but would blow coolant out the overflow reservoir when the motor was turned off.. So he bought a burping kit and that helped, and we replaced the radiator cap ( again) because we thought the new one might be faulty. Seemed like it worked, for a few weeks ,no overheating.
Now it is overheating again. It is fine on the faster roads, but when we get to the woods where we drive slower, or go up hill it overheats and the coolant blows out into the expansion tank when you shut it off . He took the thermostat out to see what happens, and it still overheats.
Does this seem like a head gasket? We haven't done the leak test, don't have the kit yet. The weird thing to me is that it is not loosing any coolant, the oil isn't milky either.
What else could it be?
i hate to have to buy another rig for going into the woods, but we have to get this thing figured out. I want to take it to a mechanic, for a look by a fresh set of eyes, but Hubby doesn't want to, and just wants to give up.
Thank you for any advice!

 

Oh forgot to add he hardwired the fan also

 

Here is everything to replace or check for the cooling system, in no particular order.
1. New or flush radiator.

2. A good 195 degree thermostat.

3. Make sure the system is completely filled with coolant. make sure the heater is running when filling it. Make sure the reservoir is at the correct spot.

4. Make sure the system is full with no air....haha.

5. A new water pump may be necessary even if no leaks are visible. The blades can rust and not being propelling the coolant correctly.

6. A fan clutch. Helps keep it cool at lower speeds...wink.

7. The E-fan should kick on at a little passed 210 on the gauge. If hot wired kick it on around 210 and you should be good. Mine is hot wired as well.

8. Make sure the system is completely filled with coolant....haha.

9. How old are your upper and lower radiator hoses. They apparently can get so worn out they suction closed on them selves.

10. Fan shroud?.....some say this helps them run a little cooler because it helps the air funnel directly over the radiator. Though many, including myself, run no fan shroud for years with no problem. That being said I do believe it could help in some small way but doubt this would be your problem.

11. Make sure you have a good radiator cap. You already said you have tried 2 and doubt both are bad.

I think that covers everything. I would guess your problem is the system is not completely full or the fan clutch since you said that is happening when at slower speeds or stops. Since your radiator and cap are new, if all the other stuff checks out I'd change the water pump.

I think I covered it all.

 

I'm leaning towards the fan clutch too. If it were overheating at higher speeds, I'd say it's probably a head gasket. But since it's only at low speed it's probably because it's not getting enough airflow.

I also don't have a fan shroud. It fell off one day and made a hell of a racket. It's been in pieces in the cargo area for over a year now.

 

We do have the fan shroud, so that's not it.
I don't know about the fan clutch... when he is in a mood to talk about it I will ask.
I mentioned the water pump the other day and he didn't want to talk about it. I get it, he's put in a lot of effort to get this thing fixed. That heater core replacement was a sight to see! Wow.

 

Fan clutch was replaced within a year. Water pump was replaced a few years ago, the same time as the radiator. Maybe we should check it.
It's always ran hot in the hot weather, in the past we could run the heater and it would be ok.

 

The cooling system on these should be kept working at 110% efficiency so it should be kept in top shape. It's not that expensive to replace the whole system and other than the heater core it's not a hard job at all.

 

What parts are you suggesting we replace again?
thank you

 

Yes! This is what that looks like. Note that there were ZERO external signs that this water pump was bad.



Fins gone. Not moving much coolant. Just enough to fool you!



Yes, I think you did!

Almost!


crowinghen, don't fall for the trap of trying to "upgrade" your cooling system. We have quite a few members here who live in very hot climates who run stock systems and have ZERO problems with overheating, even in slow traffic in the summer.

We have seen countless people come on this forum with overheating problems who have spent many hundreds of dollars putting in uber-cool aftermarket upgrades, and still have problems. This is because they did not troubleshoot methodically and find the real problem.

The stock system does a great job when it is in good working order. You just need to find out what's wrong.

I'm betting on the fan clutch or the water pump, and no, you do NOT need a "high flow" water cooler!

 

I second checking the fan clutch as it's simple to check. If he went super cheap on the replacement water pump, the blades might be gone. I've seen a rash of cheap chinese parts only lasting a few years, although with the water pumps they usually start leaking first.

 

I've read two different things about the fan clutch-
if it freely spins its broken
if it freely spins it is fine
what is the best way to check the fan clutch?
thanks!

 

It should turn with resistance. Imagine turning a fan in pudding. It should be harder to turn when hot.

 

The truth is, it's hard to tell. I'd just replace it.

 

(Pudding! Dean Winchester does a little dance)

Cold, you shouldn't get much more than a few rotations trying to spin it by hand. Hot, less than a rotation. But at this point, instead of continuing to guess, just replace it.

 

First slight overheating problem I had after getting my '96 was due to the fan clutch. As far as testing goes they can be good,bad,or in-between.
In 2016 the radiator developed a crack so I replaced it. Also:
-water pump
-radiator cap
-all hoses (eliminate the heater control valve in the heater hose. Plug off the vacuum line to it).
-thermostat (housing was fine)
-water pump inlet tube (I used 5/8"hose barb x 3/8" npt brass fitting instead)

I also went a replaced the idler pulley and belt.