NotMatt
NAXJA Forum User
- Location
- Wenatchee, WA
Pulled the radiator off my Comanche to make it easier to track down a power steering leak, and replace the alternator at the same time. I got to thinking about the ZJ fan clutch upgrade that lots of people do with a Napa fan clutch...
So I pulled the stock mechanical fan and clutch combo off the shelf that I removed from my 4.0 YJ when I put an electric fan on, and lo and behold... the YJ fan clutch fits on the MJ/XJ fan, appears to be identical to the ZJ clutch from pictures I've seen on google images, and fits behind the radiator with about 3/4" to spare as well.
Now, I'm not so sure it's really done anything for my cooling... it's getting to be colder up here, so and my rig never really has had a problem idling for long periods, but I CAN tell a difference in noise that tells me the fan clutch is locking up a little more than the stock one I pulled off.
So, just another option I guess if you happen to have a six cylinder YJ fan clutch sitting around.
And, finally... a wild-azz educated theory check guess... the fact that the YJ and ZJ fan clutch has more fins on the front side of it compared to the stock one which is flat, does this translate into the clutch itself "soaking up" more heat from the engine bay, in turn making it transfer more heat to the fluid inside, thus making it lock up sooner/harder than the factory XJ/MJ one, or am I just crazy? Or is it the heavier duty spring on the front?
So I pulled the stock mechanical fan and clutch combo off the shelf that I removed from my 4.0 YJ when I put an electric fan on, and lo and behold... the YJ fan clutch fits on the MJ/XJ fan, appears to be identical to the ZJ clutch from pictures I've seen on google images, and fits behind the radiator with about 3/4" to spare as well.
Now, I'm not so sure it's really done anything for my cooling... it's getting to be colder up here, so and my rig never really has had a problem idling for long periods, but I CAN tell a difference in noise that tells me the fan clutch is locking up a little more than the stock one I pulled off.
So, just another option I guess if you happen to have a six cylinder YJ fan clutch sitting around.
And, finally... a wild-azz educated theory check guess... the fact that the YJ and ZJ fan clutch has more fins on the front side of it compared to the stock one which is flat, does this translate into the clutch itself "soaking up" more heat from the engine bay, in turn making it transfer more heat to the fluid inside, thus making it lock up sooner/harder than the factory XJ/MJ one, or am I just crazy? Or is it the heavier duty spring on the front?
