Another overheating thread

I've had it with my 00 XJ. I've replaced water pump, flushed the radiatior due to sludge, replaced t-stat, and finally today installed a ZJ fan clutch. Still overheats if you let it sit more than a 2 minutes with out moving. As soon as you drive it drops to normal temps. Coolant is a gross brown color. Always has been even after a good flushing. What the hell do i do next?
-B_palmer22

Keep flushing with distilled water every week untill it is clean. It is probably still full of sludge. Flush, fill with distilled water only, drive for a week, flush, fill with distilled water only, drive for a week, keep doing this untill it is clean after the week. Only then refill with the proper coolant mix.

I'd just replace the radiator...You can go round and round with the cooling system, but if the radiator is bad, nothing will help other than a new radiator.

ParadiseXJ said:

I'd just replace the radiator...You can go round and round with the cooling system, but if the radiator is bad, nothing will help other than a new radiator.

Click to expand...

I agree with this. Do a bunch of flushes and I'd use a flushing additive at least once, maybe twice. THEN replace the radiator.

Be aware that any overheat leaves you at risk for a cracked 0331 cylinder head. The factory head has a casting defect between cylinders 3-4 which has a tendency to crack upon an engine overheat.

Take it to a GOOD shop and ask them to flush it for you.Stop playing with it.During the summer our temps are around 110 to 118 every day and mine doesn't over heat running the AC.(on or offroad)I have a stock setup in my 89 with a closed unit, you know the one they say doesn't works.My temps 195 to 200 and i think 200 is hot.I did this 5 years ago so it is time to do it again.
Peace of mind is cheap if you ask me.

Radiator has been completely flushed in the last 3000 miles. im starting to suspect its the head. However, it doesnt eat coolant. It always has kinda run rough.

Flushing the rad works OK - up to a point. If the rad core is badly clogged then nothing
beats taking off one of the tanks and "rodding" out the core. Only a qualified shop is
able to do this right. Get some estimates, and weigh the cost against getting a new rad.

Agree that if the Radiator has been clogged just going w/a new/better than OE radiator.

Why spend the money trying to fix/flush this one and just apply that to the new radiator.

Had to replace several coolant related things on my '01 XJ and adding a new 2-core all aluminum radiator really helped. Next step for me will be hood vents/louvers to allow the heat to escape during slow speed driving or idling. Those pre-cats on my '01 XJ are like huge ovens and there is just no place for the heat to go to escape on my rig currently when idling in traffic.