spirittea

1988 XJ 4.0 the engine seems to be a rebuild runs like a top
clean as can be inside and out last week it started boiling over LARGE!!! so i decided to overhaul the whole deal thermostat-waterpump-fan clutch- serp belt-i even replaced the secondary elec fan to my dismay im still back to square 1
{my first thought was i got ahold of a bad NEW THERMOSTAT}
while i was insalling the elec fan i noticed both tanks on the rad were hot the grids were not.
can yall comfirm my thoughts that ive got a plugged rad???

Rainycity

That would be my guess.

spirittea

i flushed the system n seemed to find some air pockets.
it stayed cool 4 a day daqy 2 it redlines again i hopeing i was sold a s#!t
thermostat
and the rad seems to have flow unless it just messing with me

cherokee country

yes try replacing the radiator it basically is the last part you have not changed. i speak from expierience (96 jeep country 4.0) over heated daily in the summer. i would run the heater to help keep the engine cool...try that when its 95 out. i replaced all the parts you mentioned except the electric fan.still over heated so i dropped 150$ on a stock type radiator and installed...over heating problem went away.
I notice my jeep will heat up during the summer still at idle, until the electric fan kicks in at 215 degrees or so. it cools right down and just keeps cycling that way. i think its because of the mechanical fan can only cool half of the radiator. so the electric fan cools the other half as needed. besides 4.0 s run at about 210 anyway even with a 195 thermostat in it. jeep did not design the best cooling system for the cherokee or maybe we should blame renault for thier involvment.
oh yeah when i replaced that radiator i pulled the tanks on it and had a radiator shop check the tubes....40% blocked . you should have seen the goop that came out. good luck

spirittea

if its just half plugged. i can pour fluids in it and still think thiers flow
and im in Ohio where its neon cold out right now.
ive got the elec fan wired into the ign just cause in **** that way.
but i dont like xtra draw on my power .if i can square this deal away i need to fix that
im prolly gonna take ur advice AND get another thermostat cause im convinced auto zone sold me a POS<the **** thing again
i really have to stop shopping there

trapper

I was just told that CLR was a great way to un-booger a cooling system.

detach top and bottom radiator hoses.. let drain to its new level.. reconnect bottom.. pour 1/2 a jug in the top hose.. reattach.. fill the system.. then let run for an hour or two.. then flush the system A LOT to get all the crap out..

try searching CLR / radiator flush or CLR / cooling system flush

better than tearing it all apart and if it dosent work.. you will anyway

good luck

truckntractorhick

test ur new thermo with boiling water!