Watercooled / Radiator Help Needed, Radiator not consistant temp... Options

[pankopp]

Hello everyone,

I am having a few issues with my Renegade conversion for the first time and cannot get my head around it. I recently did some work on my EJ22 Subaru motor involving oil pan replacement and a few changes to the intercooler setup, nothing major and nothing that should have affected the cooling system. (IMG:style_emoticons/default/dry.gif)

My issue is that the car starts and warms up perfectly fine, but after it gets to operating temp (~185*) the thermostat opens, heats up the radiator, circulates coolant, and turns the fans on.

Everything sounds normal, but after driving for about 20-25 min. I notice that the fans haven’t turned off ever since they initially turned on. Temperature stays around the normal operating level, may climb a little at a stoplight, but all seems normal.

When I park, I have been checking the radiator end tanks and on the passenger side with the inlet and outlet coolant passages and the fan switch, the tank is very hot. The opposite side with no connections, just air release screw, is cold (ambient temp).
It’s almost like the radiator is only flowing half the volume, as in passenger side half, not top to bottom half.

Temperature outside her this morning was 54*, so there should be no issues. I have bleed, burped and refilled the coolant just as I have in the past. When I open the air bleed valve on the top drivers side of the rad. very little, to no air escapes, just coolant.

Any ideas or recommendations would be a huge help. Thanks in advance!
-Andrew

[Jeff Hail]

I have seen a lot of double pass radiators. A lot! and never one plugged.

1) Make sure ALL AIR is burped and purged from the core and remote top tank. Fill it cold, engine off with upper hose disconnected. Jack up the front end so the core is higher than the top of the engine. Reconnect the hose, top off as needed and let it run (front end up). Keep checking for air bubbles. Slow vent to purge.. you want coolant to push the air out. Turn it off, set car on level ground and check it again for operation.

2) Double pass radiators take a little more to pull coolant through them. If the pump is in good shape move to the next item

3) Thermostat in backwards? No? proceed to next step.

4) Get another thermostat. If its hot on one side and cold at the outlet it isnt flowing. Thermostat is bad. Pretty common issue.