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My 91 Cherokee is overheating. I checked the compression and it is 120 to 130 lbs in all cylinders except #1 is 100 lbs. When the engine is running and hot the upper rad hose never feels like it has fluid in it, it is easy to squeeze shut.There is no smoke coming out anywhere. My oil does not look like it has water in it. Could my rad be clogged? does it sound like a head gasket?

Thanks  

change your radiator cap....

when you take it off.. look at the bottom...  the center disc in the middle of the rubber gasket..  about the size of a dime...

see if it hangs free... if it does ... replace it with one that does not... some are spring loaded...   some are not...

the spring loaded versions have solved the problems many times..

warning..     you might want to change all your cooling system hoses...  the upper and lower radiator hose.. the various bypass hoses and heater hoses...

when cars run for a long time without cooling system pressure.. the hoses take a set... a relaxed set...  when you put the system back under pressure.. they quit.. the hard way.. they explode.. sending all the expensive green stuff out onto the ground...

i worry about the low compression on the first cylinder.. but test it warm later..

the problem with it is...   the water pump pushes the coolant back around the cylinder walls in the block..   upward through the back of the head.. forward through the head...  to the thermostat housing on the front of the head...  when there is no pressure.. the coolant can boil... sending gas bubbles forward... the front of the head usually gets the worst of it...  

I own a 2001 Oldsmobile Aurora 4.0 V8 and it seems that we can never keep enough coolant in.  The other day, I was dry on coolant so my husband and I added some.  After the coolant was added, we were driving around for about 1 hour and when we stopped and turned the engine off, all of the coolant drained like a waterfall from the bottom and spilled everywhere.  The car is not over heated yet though.  I had an opinion that this was not worth fixing and to junk my car.  I do not want to do that if it is avoidable.  PLEASE HELP!!      

You may as well, be having trouble with the radiator cap not keeping the proper pressure, your system is designed to capture fluid from expansion (as the water system gets hot)it flows into a reservoir, that reservoir is usually ware the cap is, it should be kept about half full. as the warmed fluid expands it fills the canister, as the engine cools the fluid is sucked back into the radiator. This is the reason why the cap is so critical on the newer water systems(coolant systems).  If you have a mechanic you trust ask them to do a pressure test on the cap, for the price of a cap just go buy one, they are not expensive.
Though you said water flushed from the bottom of the car?  you may have a radiator with a crack in the bottom tank,I think your is new enough that it may be the plastic type(tank)they do crack, again if you can a simple pressure test will make that determination for you. The over flow may drain so that it just seems to leak from the radiator. any how the thing dose not have the type price tag that will cause you to junk the car, go to rock auto .com and look it up. good luck.