got a 1990 cherokee that runs hot quick i took the therm.out, flushed it out, done a compression test and no water in my oil. about 5 to 10 min. after idleing it starts going back into my ress. with a stream as big as the hole. was wondering what yall thoughts r bot it. thanks in advance.
p.s. it starts bubbling out the ress.

 

head can be not good is there knock in the vale cover

 

radiator clogged?

 

did you do a fluid change

 

1990 isnt that renix with the closed pressure system? Did you burp it well after taking the t-stat out etc?

 

it can be water pump

 

Mine ran hot because my coolant bottle was leaking.Fix it and now it dont get hot anymore.

 

check the pump remove and inspect it ,,mine run hot and the blades on the impellar were gone I guess they just rusted away ,,new pump from the zone and prob. was solved its abt a 2 hour job...

 

Aint there like a weeping hole on the water pump that when it starts to go bad it will leak?

 

jeep85
is this the knock your talking about?
Mine does this and gets hot like 220-230 after 15min of driving