jeepxj412

On my way to my college finals the jeep started to overheat (its been doing that a couple times due to a bad radiator) and I live 5 miles away from the school. it over heated 3 times and died on me twice while at stoplights. could the overheating make the jeep die out on me? and I lost a LOT of HP after it died the first time. is there more in my future other that a new radiator? I do plan on getting all new hoses and thermostat as well. if my temp gauge goes to 260 and it was wanting to break past that.

Donnie_K

check for oil in the coolant, check compression. There is an automatic shutdown on some of these for when they overheat. better get that radiator fixed asap. and maybe a new thermostat too.

jeepxj412

ok cool I just was making sure there was a chance of an automatic shutdown. no oil in the coolant either.

99PurpleHaze

Mine overheated (in the red) on the interstate this summer and before I could get over to the shoulder it had cooled back down but never died and it blew my head gasket. You may not notice coolant/oil mix right away, I'd take it to a local shop and get them to do a head/block leak test just to be sure...

jeepxj412

well i JUST replaced the head gasket a month a go so lets hope the head isnt warped or anything like that

jeepxj412

ok well heres an update. I just got outa class and filled my radiator up with coolant. started up just fine and started going and the jeep started bucking along like it was about to die again. now i did drive it just under 2 miles after it started overheating the last time due to the fact that it was rush hour and there was no where to pull off to. could that have damaged the engine internals at all? i have to get it towed back to my house tomorrow to work on it. so I need to know what im getting myself into.

tjwalker

Your overheats could have blown a headgasket or cracked a head.

You really need a solid diagnosis here. I'd start with a compression test on all cylinders. Low readings on 2 adjacent cylinders indicate a blown headgasket.

You really, really, really do not want to overheat any engine!

robertj

If nothing else, you really need to learn to stop driving when it overheats. You don't keep trying to get to your destination when it gets too hot. You pull over and shut down the engine. You can baby it back home if you let it cool off and drive for a bit, shut it down, repeat. then figure out why it's overheating and fix it. If not, park it. Trying to force it to where you're trying to get to is going to blow your motor. If it shuts down because it's too hot, you've got serious issues. Don't be offended, but I feel bad for your XJ. And, YES, you definately could have damaged your motor.

spiceman

those i6 4.0l are very lenient when it comes to overheating compared to most engines. for those poor folks that are still using the pressure bottle... those fkkkers overheat all the time.

i wouldn't freak out too much over it. its possible that you can blow a head gasket or crack the head somehow but like i said... these motors take the overheating abuse pretty well...

1991Jeep_Man

It may be possible that the sudden loss of HP you felt was the result of the piston rings 'semi-siezing' against the cylinder walls. Someone on the forum had a similiar issue: when he pulled the engine apart, I think 3 of the piston's rings had literally tried to melt against the cylinder wall. And I don't care how tough the 4.0 is, no engine is going to handle severe overheating 4 times (twice to the point of shutting off) and not suffer internally. IMHO, I think you seriously messed up your engine.

brutalxj

My jeep has been pegged way over red to many times to count! Every time it happened to me I was on the verge of being stuck. The 4.0 is an amazing motor but not all of them are in the same condition. If it dies its telling you to stop driving it until you fix it!! Don't you have a friend you can get a ride from?

Ender

wow yeah, I've overheated before (darn pressurized coolant bottle). The 4.0 is def tough, but this guy sounds like he has pushed his too far....

spiceman

lol sry you're wrong

1991Jeep_Man

Really ? Where is your info to back up that statement? Unless you've found some engine made of titanium-alloy or something, then I am right. The 4.0 can easily handle the occasional slight overheat (maybe not the 0331 heads though), but when you completely burn the thing up to the point of cutting off twice, then theres no way that SOMETHING hasn't suffered internally for it.

tj40

I agree with jeep man, I would shut it down for now on with any car when it starts to creep into the red. The only thing in your favor is that its all cast iron. Well block and head that is..... Try over heating a 3.8 ford v6 one time and see what happens.