Roaring fan after changing Thermo housing

[Brandon Brooks]

Hey everyone,
Like the title says I just replaced my thermostat housing. I put the new Dorman assembly in and bled the air as best as I could tell. The problem now is at lower RPM, under load, especially with the AC on, I get a roaring that I assume is the fan. I say assuming because I can't really get it to do it when it's parked. Also, the system is holding coolant and the temperature holds steady right in the middle. Anyone have any idea what the problem could be?

 

[Brandon Brooks]

Ok I've also checked the fan and it's spinning with some resistance so the fan clutch seems fine. Just the fan surge under load with a corresponding loss in engine power. It only happens with the AC on and only after about ten minutes of driving. If anyone has any ideas ifI really appreciate it.

 

[974X4BLACKSPORT]

Sounds like a bad fan clutch.

 

[michael loibl]

Fan clutch should tighten up a bit with AC on, and under load at low RPM by design. Of course, if it’s doing so more than it was in the past, I would be curious as well. There’s a good chance you still have a little bit of air pocket in the coolant, and that could be causing the electronically controlled fan clutch to engage more aggressively

 

[F SANE IL]

i had fan roaring cause there were still some air trapped in the system.