Novak Conversions Jeep Wrangler TJ engine mounts

Radiator fan hitting shroud

H

Hnk

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My radiator fan in my 99 4.0 is knocking the fan shroud at the 6 o’clock position when started in cold weather (~20° or below). The knocking stops once the vehicle is warmed up. I can manually stop it by barely pushing down on the shroud to give the fan clearance. It also appears that my coolant reservoir is pushing against my power steering pulley at times. The pulley has rubbed a hole into the reservoir. It’s not touching all of the time.

I have no idea how long the reservoir has been making intermittent contact with the pulley. The problem with the fan hitting the shroud is new, and it only does this in the cold and until warmed up. I can’t make sense of the scenario.

I haven’t made any recent changes to the Jeep.
 
I had the same issue, but mine was a result of not using the correct mounting holes after I had removed it. Obviously that's not your issue. I don't know why it would be temperature dependent, but I'm wondering about your motor mounts & transmission mount.
 
Check your engine mounts. Check to make sure all the bolts are on the shroud...very common for folks to get lazy and ignore a few. Check your water pump bearing for play...does the fan wobble, it's riding on that bearing.

IMG_20260126_121456.jpg


-Mac

P.S. Completely unrelated but if you have worn out rubber parts... completely common after 25 years... replace your crank pulley...it has a rubber core.
 
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I had this same issue and it ended up being due to worn out motor mounts that allowed the fan to start hitting the bottom of the fan shroud. Fresh motor mounts put it back where it belonged.
 
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IF you have an automatic transmission; you can test the engine mounts by placing the transmission in D, hold the brake and apply a little bit of gas pedal.
IF the engine tilts too much then the engine mount rubber is separating and the mounts need to be replaced.
I would inspect the transmission mount too.
 
Given the age of the mounts that makes sense, and I’ll be chec
GregBelleville said:
I had this same issue and it ended up being due to worn out motor mounts that allowed the fan to start hitting the bottom of the fan shroud. Fresh motor mounts put it back where it belonged.
Click to expand...

Hey there, motor mounts seem like a consensus among answers so I’ll be checking those today. When you say you had the same issue, did yours also stop once it was warmed up?
 
Hnk said:
Given the age of the mounts that makes sense, and I’ll be chec


Hey there, motor mounts seem like a consensus among answers so I’ll be checking those today. When you say you had the same issue, did yours also stop once it was warmed up?
Click to expand...

No, in fact it took me quite a while to diagnose that it was the fan hitting the bottom of the shroud that was making the noise I was hearing. It would typically only happen when I was taking off from a dead stop. Finally the fan had enough and cracked the fan shroud which I noticed and then made the discovery that the motor mounts were shot.

I replaced the motor mounts and the trans mount with the Anchor brand kit on Rock Auto.
 
GregBelleville said:
No, in fact it took me quite a while to diagnose that it was the fan hitting the bottom of the shroud that was making the noise I was hearing. It would typically only happen when I was taking off from a dead stop. Finally the fan had enough and cracked the fan shroud which I noticed and then made the discovery that the motor mounts were shot.

I replaced the motor mounts and the trans mount with the Anchor brand kit on Rock Auto.
Click to expand...

Thank you!
 
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Novak Conversions Jeep Wrangler TJ engine mounts
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