How HOT can it get?

[BARILLMS]

Whats the MAX temp. the 4.0 can get up to before you starting doing damage? I boilled the $#!& out of mine this past weekend.

[87manche]

that really depends on a lot of factors.

let's just say that the 4.0 is an all cast iron motor, and will take a lot more heat than an all aluminum motor.

I boiled mine over, needle was off the guage, I'd guess 280 before the coolant tank popped.

 

still running that same motor a year later.

[pingpong]

Depends... i would definatley keep an eye on your oil and coolant for the next few days.

 

Side note why did you over heat it

[BARILLMS]

I have an electric Ford Taurus fan, and it quit working. I wasn't aware that it wasn't on. It was the maiden run for the old MJ. It blew the inline fuse in the beginning of the trail ride.

 

It was 90 degrees and no breeze. I basically drove the damn Jeep around then entire trail ride with the temp between 240-270.

 

I was stopping every 20 minutes or so, and letting it sit in the shade and cool down. It was hot.

 

Finally, at the end of the day, it finally started boiling and steamed off.

Then I realized my fuse was blown, and direct wired my fan up on High speed setting and it ran at 210-220 all the way home.

 

I started it up last night, and it sounds fine...

I'll take it for a test drive this weekend and see if she's ok or not.

[DirtyComanche]

Wouldn't worry.

 

 

I buried my temp gauge, then it built so much pressure it blew the block heater out of the block...

 

 

The engine quit running about 30 seconds after that. Figured I'd let it cool off.

 

 

I still run that motor in my MJ.

[Oizarod115]

wouldnt worry...

 

i ran my jeep at 260 for 6 months or better before i wised up that the gauge was right.

 

this includes many 100 mile trips to my brothers house with the gauge toying around in the red. :roll:

 

still run that motor been 10 months or so since i cooled her off.