Cooling System Problems any Idea on how to make it run cooler?

[5spdcherokee]

Ok well from what I've heard the Cherokees run a little on the warm side some times. I have a 90 5spd Sport and well it runs ok well it runs and that's about all it does then get hot and over heats. I've come to the conclusion that the head is probably warped after repalcing the head gasket and thermostat it still over heats and smokes like a SOB. The smoke smells like anti freeze so I'm pretty sure the head is screwd. Ok well I want to know if there is any modifications I can do to keep this thing cool in the future after I get a new head on it.

Thanks Chase

 

[Bounty__Hunter]

You can upgrade the radiator to one with more rows, add hood vents, throw a pusher fan in front of the radiator, make sure air is bled from the coolant system properly, convert to an open coolant system like on later model XJ's, etc.

Lots out there to do, once you tackle the problem of getting coolant into your cylinders.

 

[Saurian]

Where are you located that it's so warm, you're overheating so badly... Not to say it's exactly been a cold winter anywhere, but still... Got several suggestions that may help, don't know how strong your area of automotive expertise is, so forgive if I'm being redundant

OK, besides the obvious head problems, overheating... First and foremost, have you taken it wheeling through any mud, or water then dusty road? The radiator setup on the Cherokee allows for so much mud to get in there and turn into a solid block once heated, pretty much totally restricting your cooling system, if the air cannot pass through the radiator, you're pretty much guaranteed to overheat.

Are your fans working? One is a belt-driven fan with clutch, the other, an electric... Spin the belt one (with the engine OFF, of course). If it turns really freely, your fan clutch is probably toasted, if there's some stiffness or resistance, you're in good shape... As far as the electric one goes, to test if it is working, pull the wire off the temperature sensor on the thermostat housing with the engine running. You will throw a Check Engine light, and the electric fan should start running, if it does not, there's a problem in the power supply for such.

What kind of coolant are you running? A 50/50 mix is preferred, straight up coolant will NOT perform anywhere near as well as the mix... And never ever mix the orange GMC Dex-Cool coolant with standard green coolant, with the exception of that "Mixes with anything" stiff, your coolant will turn into a delightful jelly like substance, which is not good for cooling. If you're getting air into the system, either through a leak, or a faulty radiator cap, this will make you overheat as well. The cooling system depends on a certain amount of pressure to regulate the boiling point, and keep you from cooling, rather than superheating the coolant.

And failing all that, how long has it been since you've backflushed the cooling system, if there's a bunch of sludge and such trapped in the heater core, or anywhere else in the system, it'll be causing it to not cool as well...

You're not gonna be able to do much, though, till you get the head repaired... Hope it's just the head, and you didn't crack the block. Best of luck to ya

 

[jakbob]

i know i had heating probs with my 95 xj...it had a 4cyl but i upgraded to a larger radiator and replaced my water pump...that could also be the prob...

 

[5spdcherokee]

Where are you located that it's so warm, you're overheating so badly... Not to say it's exactly been a cold winter anywhere, but still... Got several suggestions that may help, don't know how strong your area of automotive expertise is, so forgive if I'm being redundant

Ok well I never siad it was warm were I live, I'm in ohio and I just bought the jeep. I've checked everything that is pretty much common sence. When I replaced the head gasket, the 3rd and 4th cylinder were partially layin full of anti freeze and you could see on the head gasket were it was burnt. So like I said I replaced the head gasket it ran fine for a little while then started acting up again. So I'm pretty sure it's the head. Cooling mix is 50/50 and I have control over the electric fan because the last owner sniped the wires on it and so I just took the easy way out and wired it to a switch on the dash so I know it's on. And yes it's blowing/sucking what ever you want to say, the right direction. The clutch fan is fine that was one of the first things I checked. The only thing that I havent done is flushed the system. Made sure the little cap on the colant tank was tight. Like I said I just bout it about a month ago. Never messed with jeeps only Chevy and Dodge's. The coolings system is new to me on these things I'm used to the regular cap on the radiator style system.

 

[Saurian]

Do you have that mysterious closed cooling system? Meaning, is there a cap right there on the radiator, or just the one on the overflow tank... If it's the latter, you've just left my area of knowledge in the dust...

With mine, when it started overheating so bad, the coolant flush helped it out a lot. That, and getting all the mud out of the radiator, it still runs a little warm in the summers, but then again, there's still a lot of mud in the radiator...

Best of luck to you with this, I'm sure someone on here has the answer

 

[Bounty__Hunter]

His should be the closed coolant system, no radiator cap.

 

[5spdcherokee]

Yep It's the gay closed system.

Thanks though for the help.

 

[dingus]

sounds like you have a cracked head

 

[LBR]

Replace the lower radiator hose with a new one. They can collapse internally (water gets between 2 layers of rubber and swells the opening closed) and starves the water pump of coolant, but still looks and feels OK. LBR

 

[jakbob]

yeah but would that cause coolant to build up in the cylinder?

 

[LBR]

My reply was for the overheating issue LBR

 

[jakbob]

When I replaced the head gasket, the 3rd and 4th cylinder were partially layin full of anti freeze and you could see on the head gasket were it was burnt. So like I said I replaced the head gasket it ran fine for a little while then started acting up again.

well we know its not the hoses, if his head is warped, its warped...just need a new one...

 

[dingus]

if it isn't warped too bad, you can also take the head to a machine shop and they can shave it down for you. with a smaller combustion chamber (higher compression ratio), you might even see some power gains!

 

[NCjeeper]

im having the same problem. it used to run at about 210 constantly... suddenly one day it jumps from 210 to near 280 in a split second, and started doing it more and more. i replaced the thermostat and gasket. it ran like normal for a day or two and then it's done it twice since then. when it overheats i can hear a light noise from near the thermostat housing, but i think that's just the water boiling in the metal housing... the radiator cap hisses, but not any louder than the housing. light steam comes from the left hand (passenger) side of the radiator, but its only done that recently. im really not sure what it could be.... i replaced the thermostat and gasket myself. my auxiliary fan doesnt come on. i didnt try what Saurian said yet about trying the wire because im not at home..but i will. i cant get it to turn on for the life of me. ive tried putting the heat on defrost. no luck. my serpantine belt's a little loose... im sure that could have something to do with it, but its only started squeaking a bit within the past few days.... about a week after replacing the thermostat.. god help me

 

[NCjeeper]

lol oh and btw i have a 99 xj sport

 

[NCjeeper]

i added some "radiator stop leak" and it doesnt steam anymore. its not leaking anywhere. i had an obd-II test done and it came up with two errors, auxiliary emissions, trans range sensor, and coolant temp. circuit high input. where can i find these that maybe are a little cheaper than going to the dealership or advance? advance couldnt find the auxiliary emissions i need on their computer. any suggestions?


thanks

 

[5spdcherokee]

Well I had a pass run on it then had it magnafluxed and found 2 cracks on the #4 cylinder so I just went a got a new engine. Yes I said a new engine. with less miles and no cracked head. $300 for the engine or $175 for a new head. I opted for the engine.

 

[NCjeeper]

fixed! radiator fix leak, addatives, another thermostat, 180 degree this time, flushed the radiator, reset all the codes, wired the fan to auto on when the engine's running with a switch so i can shut it off when i want.

 

[90growler]

Some body told me that you could upgrade the water pump as well with a dodge high perfomance WP. My brother had an XJ that overheated and some mechanic installed one and it is fine now. Don't know what WP he did it with.