Mechanic? Mechanic??? Hell no, try and fix it yourself!

There are a lot of things it could be. Coolant level, radiator cap, thermostat, etc, etc. What have you checked so far?

 

"Mechanic? Mechanic??? Hell no, try and fix it yourself!" LOL! When someone mentioned at 260 the head gasket is in danger I figured I better take care of this rather than using the heater fix!
Coolant level is 1.5 above the add line. There is no visible leakage. When engine is off I check the fan rotation and it turns with some resistance but doesn't freely turn. I don't see where the temp sensor is so I can check it for looseness. We just moved and the Haynes manual is in the garage somewhere!

 

... We just moved and the Haynes manual is in the garbage somewhere!

Fixed your glaring typo

Glad it worked out for you :thumbsup:

 

I've got a Haynes manual, but the more I look at it, the more I don't like it. Do yourself a favor: buy a hamster, put the Haynes manual through the paper shredder, and then use it for Hamster bedding.

You might have a water pump going bad on you, but check the thermostat first, though. Your radiator cap is intact and functional, yes?

 

Do a pressure test on the cap and radiator. Have you flushed the system?

 

Not sure what functional means with the cap but its not leaking. Cant remember when I last flushed the system. Is that a service they offer at Valvoline ? I think that was done before last winter! No probs with this vehicle and the radiator was replaced about 3 years ago. My stupidity if I should of flushed this sooner!
I just ran over to the bank and back no prob but idled in the drive and suddenly check gauge and needle was on 260 very quick. Jumped out and the fan was on but the radiator didn't feel hot. Jumped in and crancked the heat on and no effect. Revved the engine to about 2000 rpm and no effect. All very quick I turned engine off. Now when I checked the radiator was hot (perhaps it was hot before but not on the very top where I checked) and there were drips of oil coming from the seal below where all the cogs come out of the engine front in other words the front seal of the engine block. I've seen this leak before but never on the ground I'm thinking that points to much heat!. After about a minute I turned it on and the guage is normal.

 

It sounds like a bad thermostat. I would go thru the cooling system, i.e. flush the radiator and heater core, replace the cap and thermostat, and maybe even do the water pump. Make sure there is no mud or debris in the fins of the radiator as well.

 

I ran into a similar issue the other day. Was driving in 90* weather and looked down to see a check engine light on and the needle just into the red. I freaked out and with only 1 mile till home, i kept an eye on the gauge. About a half mile from home, the needle jumped right back down to about 220*. It wasnt fast sweeping but from red to 220* almost instantly. This is the only time ive seen this since i purchased my 1997 4cyl a couple months ago. Any ideas on that?

 

Thanks everyone for all the advice! Turned out to be a bad thermostat. That was replaced, the coolant was flushed and changed and the fan belt was a little worn and replaced. The oil was changed because of the high engine temps before the repairs.

 

So mines beginning to do the whole temp spike thing... Everything seems to be fine though but I stopped and turned it off and a crazy loud *** bubbling sound was coming from the radiator.. Just flushed and did all that last week too.. Hmmm any suggestions.. And yea I read through y'all's ideas and everything seems fine..

 

Beachjeeper1223 - So mines beginning to do the whole temp spike thing... Everything seems to be fine though but I stopped and turned it off and a crazy loud *** bubbling sound was coming from the radiator.. Just flushed and did all that last week too.. Hmmm any suggestions.. And yea I read through y'all's ideas and everything seems fine..

Be sure you have topped off both the radiator and the reservoir. Oftentimes after a flush you need to top it off after running it a bit. If the coolant in the reservoir was boiling (crazy loud bubbling noise?) then it is likely your pressure cap malfunctioning.

 

Well I let everything cool. And it's almost dry in there.. Pretty sure I got a leak somewhere but just don't know where exactly cause I can't see a single thing.. I just got the jeep a couple weeks ago and I'm trying to do everything I can myself.. But I'm gonna be honest it would be a lot easier with some guy help lol. I have a lot I'm doing on it... New spark plugs new serpentine belt new tires(35s) rewire my hella lights since the idiot before me messed them up and now there's a short somewhere.. And now I guess a new radiator.. Ugh the struggles of doing it alone... And having all my guy friends constantly busy.. Least I know what I'm doing for the most part..

 

I'm late to the party, but am having the same issue. put in a new radiator cap, new superstat thermo, and inline flushed the coolant. Still have the same problem. Runs between 192-215(?) at the highest, then jumps up kissing the redline. turn on the heater and after 30 seconds it 'pops' down to 220 again, quickly, like if you were reading a electrical circuit and the current suddenly changed. a guy at Jeep Beach said he had the same problem, that it was vapor lock and stalls his engine, but mine runs fine during the episode. any other thoughts?

 

Did you get to the bottom of this problem? I have the exact same symptoms on mine

 

Did you actually create an account here just to post this?