1991 briarwood 4.0 185k

The other day it was about 95 or so out i was on the highway keepin it between 70 and 75 mph. the highway i was on has about 10 or so miles of petty steep grades. So on these inclines i hit the trans power button just so i dont have to floor it to stay at 70. Jeep always gets a little warm when driving like this but this time i started to worry when the gauge was really close to line before red. Then i looked out the review and she was blowin white/gray smoke pretty bad but when the road leveled out and the jeep cooled off it was fine again.
also the road i take to get to work is about a mile of very steep grade. jeep gets up that pretty good but when i park i back in so the rear end is up a little and the temp gauge will start climbing about 220. other then long inclines i dont really have over heating problems. thermostat is new low/upper hoes, rad is new and has clean coolent. water pump doesnt seap.

so anyone got any ideas for me what i can do and is the smoking thing when it gets really hot something i need to be concerend with?

 

White smoke usually means water or coolant getting into the combustion in some way. Maybe a small head gasket leak. Could be as the water temp/pressure rises above normal on these inclines it is making its way past a small gap in the gasket which otherwise it doesnt?

 

right only smokes when its real hot. so besides rebuliding the engine cause of gasket, what will help keep it from getting hot like that? high flow waterpump? and whats the deal with the rear being up higher then the front when parked the temp starts climbing? oh once while parked like that i reved it engine hard a few times to see if thermo was stuck or something and it blew smoke.

 

no ones got anything else for me on this?

 

Do a compression test to confirm or rule out a head gasket.

 

did a compression test today. First thing i notice were all 6 pugs where white from being to hot and they only a year old proble 6 months ago i started using 89 at the pump and am getting better mpg now so dont know if that could be it or not. I did replace the plugs and jeep started up nice and sounded smooth at idle again. but im thinkin the plugs well be white again in no time.
well test went:

cyl 1crank 7cranks

1) 90/150
2) 90/140
3) 95/150
4) 115/165
5) 115/170
6) 90/150

from what the books says high compression is from carbon build up...looking in side the holes looks like carbon is in all cylinders i guess in side 4 and 5 it was a little darker in there and the plugs were a little worse.

so what do these numbers mean to u guys? and still whats up with over heating like that going up hills, assuming its the root of all my problems.