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Still overheating???

C

cobrasatellite

NAXJA Forum User
Location
Corsicana
So i was sitting at chase bank and all of the sudden my hood started pooring white smoke. I killed the motor and poped the hood passanfers side liner was wet. The upper radiator hose wasnt even hot so i suspected a thermostat, i replaced the thermostat at chase and started to refill radiator and fluid starts hitting the ground. Got out y flashlight and found a 6inch crack on he passangers side radiator. Trailered it home. Today i changed the Radiator brand new 1 and put in a remanufactured water pump (it was in stock and 19.99) replaced everything and let it sit for about 4-5 hous started it up and let idle. After about ten minutes it started creapin past 210 twords 220. Have a small leak from the water pump and thermostat housing. New gaskets on both and gasket sealent. Why am i still overheating? please help

1993 country
automatic
2 wheel drive
4in lift
dana 35 front axle in place (4wheel conversion)
hi flow air filter boxed off from engine bay (had for 4 months)
 
take it somewhere and have your system flushed. you may pay for it, but sometimes that can beat the frustration. overall, it seems as if you've done a lot on your own, so now with the pieces in place it should be an easy fix.
 
No point in flushing something that is leaking. You got to fix the leaks. Make sure you clean off the gasket surfaces really good. Use a small putty knife or gasket scraper that has a nice smooth blade. Get it perfect so you don't have to do it again. Unfortunately, you have the possibility of a head gasket leak or similar. Fill it all up with coolant and start up without the radiator cap. Watch for air coming out of the radiator. If you can get a coolant system pressure tester use that to check for leaks. Them pump it up and start the motor. Large pressure fluctuations (needle jumping back) and forth indicates head gasket.
 
I will be pulling it all back off tomorrow morning and putting in new gaskets. I guess maybe i missed somthin when cleaning the old gaskets. Ill see if i can get a pressure tester on it after i replace the gaskets. Thankfully there appears to be no water the oil when i checked it. (multiple times) Ill see how much my shop will charge me to flush it once ive redone everything, again.
 
Dump the coolant, fill with water, gallon of white vinegar, run for a few minutes, cap off, dump, flush clear, dump, flush clear. Let cool off, remove all the brackets including the PS pump so you have a clean shot at the WHOLE face for pump mounting. Clean it off good, take a few towels and soak up the water in the block so everything is dry. Using a small bottle of Indian head gasket cement coat the back of the pump or gasket, stick the two together, let it set up for a few minutes, coat the back side of the gasket and let it set for a few, install the pump. I actually do use a torque wrench and since I've started doing that found I have less problems than using the 'feels right' torque settings in my wrists and elbows.
I went through two gaskets trying to sneak that pump around a slightly loosened power steering bracket, now I just take the bolt off the side of the block so I can move it out of the way.
As for a rebuilt pump, never ever had any luck with them.
 
x2 on not having luck with rebuilt pumps... at the shop i work at we only use rebuilt if the customer absolutely insists on it or it is the only option.

Also make sure to check the fan clutch.
 
Check your lower hose to ensure it has an internal spring to prevent it from being sucked closed under pressure. Like was mentioned, check the fan clutch. If there's evidence of fluid leaking from the hub or if it spins easily by hand, replace it. Is your auxiliary electric fan kicking on at 190-ish?? If not, replace the sending unit for it. If the problem persists, there are aftermarket 3-core radiators, high-flow water pumps, and hood vent options that many of us on here have done. XJs are designed to run hot, and they tend to be prone to overheating if any part of the cooling system isn't working properly.
 
Ok so i finally got it all worked out..Kinda the leaking on pump was due to bad silcone.. awsome huh? so after fixing it i had a drip from the thermostat housing 3 gaskets later i robbed the thermo housing off my 91 parts jeep. After installing it and letting it dry i started it up and no leak. BUT THERES NOWHERE FOR THE THERMOSTAT TO GO. I looked at the old radiator and saw its sensor was there so i removed it and placed it where the plug was in the new radiator. I jumped the wires to old thermo hook up and the temp guage works but now i got a check engine light. If i plug the old sensor in the light goes away. what can i do to make this work?? Is the only option another thermo housing with the place for the sensor?
 
I'm confused.

On the Renix you have the Coolant Temperature Sensor (sends signal to ECU) on the driver's side of the engine block under the manifolds, the Temperature Guage/Idiot Light sender on the driver's side rear of the head, and if you have an eFan the temperature sensor for that is in the radiator.

So, I know things changed with the HO, I believe the Coolant Temperature Sensor (send signal to ECU) was relocated from the block to the thermostat housing. Your eFan temperature sensor is still in the radiator, and the Coolant Guage/Idiot Light sender is still at the rear driver's side of the head.
 
Im starting to figure that out. It looks like i need another thermo house to get this to work right. Is there a fitting that will let me put the sensor in the heater line? i dont know if i can find a house around here.
 
Well, your 91 thermostat housing should have one port for the ECU/PCM sensor, you have the sensor in the radiator to operate your eFan, and on the driver's side rear of the head is your temperature gauge/idiot light sender.

If you are wanting to add another sensor/sender, HESCO makes a thermostat housing with two sensor ports.
 
So i went and got a correct thermo housing today and installed it. I have no leaks and the system is filed. Still overheating
what i have one:
New waterpump (not remanufactured)
New radiator
New therostat 195 deg f
Newthermostat housing
New dent in passangers finder (bad temper)

ANY IDEAS???
did work in driveway 98deg outside less than 10 min and guage was just under red
 
Last edited:
Ok, your 93 is essentially "self-purging" of air bubbles, unlike the earlier closed systems.

Things that make you run hot:

Wrong coolant mix--50/50 good.
Insufficient amount of coolant--air trapped in system.
Not enough pressure--bad cap.
Reduced air flow through radiator or blocked core. REPLACED RADIATOR
Bad fan clutch.
Bad eFan (if equipped).
Bad eFan sensor (if equipped).
Radiator/engine block filled with crud.
Failed thermostat (stuck closed/partial opening).
Loose accessory belt.

You have covered the radiator.

Do you have the eFan and is it coming on?

Have you checked the fan clutch, it should be locked up once the air flow through the radiator reaches 170 degrees, when locked it should not turn without turning the shaft. W/o the fan clutch operating properly you won't have enough air flow for cooling at idle/low speed driving in town.

Have you tried parking nose-up with the radiator inlet at the highest point to let any possible air trapped in the system to escape?
 
Last edited:
cobrasatellite said:
So i went and got a correct thermo housing today and installed it. I have no leaks and the system is filed. Still overheating
what i have one:
New waterpump (not remanufactured)
New radiator
New therostat 195 deg f
Newthermostat housing
New dent in passangers finder (bad temper)

ANY IDEAS???
did work in driveway 98deg outside less than 10 min and guage was just under red
Click to expand...

Pressure cap, should be an 18lb cap not 16lbs.
 
I used pre mixed 50/50 prestone
ran water through the ner radiator and it seemed to flo out well.
e fan turns on with ac only, is that correct?
I flushed the block while all components were off.
Ill try the nose up in the morning. i can pull up on ramps for that.
I kno the clutch fan should lock up at a sertin temp but how do i tell if its good or bad?
 
The fan will roar on cold startup and then quiet down after about 20 or seconds as the fluid in it distributes itself around, then as it gets hot it should start getting louder as it engages and then quiet down as it starts to disengage.
 
cobrasatellite said:
The cap i have is 16 lb its been on there since i got it months ago never had a issue before, but could that be it?
Click to expand...

I've seen it cause problems, thats one of the reasons they put a cap tester in the stant pressure testing kit. I replace my pressure caps every other year on all 4 jeeps.
 
ok well i broke the belt tensioner bolt so after i replace at in the morning ill pick up a 18lb radiator cap. park on ramps and see how it does.
Can i add a fixed flex fan if the clutch fan isnt workin properly?
I have a few of those from hot rod projects.

(after 16 pages of searching the last page told about flex fans....cork screwing throug the radiator in water... ill save those for my hot rods i guess)
 
Last edited:
Never been a big fan of those, never had good results, if the fan clutch is bad replace it with a HD ZJ from a 97 or so ZJ with a 4.0, it's a better clutch, about $45 or so from napa. When I refill my systems I let them run without a cap for about 10 minutes and watch the coolant in the neck, you can see the air because the coolant tends to look like fizzy green soda. Also make sure your overflow tank has new coolant in it, otherwise the system will suck air back in. On the first refill I fill the overflow bottle to between the cold and hot mark. Couple of days later it's usually dead on.
 
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