Fan Blade Rubbing NX4510HST

[Username Taken]

Here are some photos and this area is where it is hitting the fan shroud. Something is torquing in order for the fan to hit the shroud. The fan is hitting the shroud at the 1 - 3 o'clock position on the shroud. I'm going to have to recheck all the bolts everywhere to make sure that they are tight. The radiator does not move at all. The pictures are of two different blades.

On some Cummins 6.7's the fan shroud will actually get sucked into/collapsed into the fan somewhat when it's hot and the engine is working really hard. It has resulted in some catastrophic cooling failures while towing heavy loads.

I might be way off-base but it's something to consider. Those fans are stouter than people think. They can move some air.

Not aware of any easy solutions if that's your problem. Maybe a new shroud but that would probably be spendy. Maybe some 'farmer engineering' might be in order. Keep the shroud, though. The radiator won't work right without it

 

[JimR]

On some Cummins 6.7's the fan shroud will actually get sucked into/collapsed into the fan somewhat when it's hot and the engine is working really hard. It has resulted in some catastrophic cooling failures while towing heavy loads.

I might be way off-base but it's something to consider. Those fans are stouter than people think. They can move some air.

Not aware of any easy solutions if that's your problem. Maybe a new shroud but that would probably be spendy. Maybe some 'farmer engineering' might be in order. Keep the shroud, though. The radiator won't work right without it

I don't see any movement in the shroud at all. Maybe I can tweak it by loosening the bolts on the shroud and trying to pull it closer to the radiator. Another thing I thought of was this. The engine was replaced roughly 300 + hours ago. I know for a fact that the fan was fine before the motor was changed. I wonder if I loosen the radiator mount bolts and tweak it over to the right 1/8 of an inch if that would cure the problem. It is hitting on the upper right hand side. I probably should also check the upper and lower clearance of the shroud. Maybe they forgot a spacer under the radiator if it is not centered. The cold weather is keeping me from playing around working on it. I might also be able to tweak the motor over a little bit to center the fan if the radiator can't be tweaked. I think it can wait until Spring.

 

[JimR]

Nice day today and a good day to figure out the problem with the fan. No bolts are loose anywhere. I found that the top of the radiator is in a good 3/8". I also noticed that the right hand oil cooler line going to the front cooler appears to be tweaked outwards. I removed that line and tweaked it back straight again. Then I put a 2 foot long breaker bar into the vertical holes for the radiator support and bent them forward. The picture will show how much I gained by doing this. How this got bend backwards is beyond me. I then decided to try and change the fan blade without removing anything in front of it. I did get a few scuffed knuckles but got the job done. Here is how I did it. I left the alternator belt tight. Raised the loader and turned the front wheels all the way to the left. I tucked myself down between the tire and tractor and got to work. I lined up the first bolt by turning the fan and put it at 3 o'clock. I used a long 10mm combination wrench to break the bolt loose. Once loose I used a 10mm Craftsman offset ratchet wrench to spin the bolt out. Using my right hand I was able to get in between the blades above the bolt and take it all the way out. I turned the next bolt to 3 o'clock and did the same. The same goes for the last two. Push the fan all the way forward and remove the pulley. It will come right off without loosening the alternator. Tweak the fan towards you and slide the spacer off. Then remove the fan. Putting it back in was much easier. When installing the hub I had to pull the bolts back a bit on the fan blade. Slide the spacer hub on and put the pulley back in place. Don't forget to line up the pulley holes with the water pump holes using a small punch or a short bolt. Once you get all the bolts started the rest is a breeze. Line up the first bolt at 3 o'clock put your right hand under the fan blade aimed at you and left hand with the 10mm ratchet wrench in above that blade. Hold the wrench on the bolt using your right hand and tighten the bolt up using your left hand. Turn the fan bade 1/4 turn and do the next bolt. Do the same for the last two bolts. I then tightened all the bolts real tight using my longer combination wrench. I hope my long explanation helps somebody that has to do this fan blade fix in the future.

 

[hornett22]

Glad you got it figured out and squared away. Probably a lot cheaper than replacing the radiator.

 

[JimR]

Glad you got it figured out and squared away. Probably a lot cheaper than replacing the radiator.

The new fan was under $75 shipped with tax. A new radiator is over $1,000.

 

[JimR]

Update on my new fan. As of yesterday my fan has yet to hit the fan shroud. I believe the problem was the radiator being tweaked backwards at the top is why the fan was hitting it. I have been using my tractor extensively since installing the fan. If I see any change I will update this post.