Fan Hitting Shroud

[otterby]

I have an '85 K2500. The original engine was a 454 but was replaced with a crate 502 quite a while ago. Over the past few years I've heard the fan hit the shroud occasionally but it stopped after a while. I could see where the fan was close to the left side of the shroud and had touched and there was a good gap on the right side. Now all the sudden the fan is hitting the shroud on the left side almost constantly and makes a lot of noise, but not always. Everything looks good, tight and straight. The motor mounts look good and I really don't see where there is any way to adjust the shroud the the left to center it on the fan. Something is obviously out of whack but I just can't figure out where. Any ideas?

[mongocanfly]

Sounds like motor mounts...have someone brake torque the truck while you watch the engine,with the hood raised...from the side,... and see if the engine lifts...

[73kay]

I have had similar issues. Check your fenders are square along with the core support. Also check the fan shroud itself is centered. Lastly just verify you have the right shroud and fan. Hope that helps.
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[Mathew21]

I would recheck the motor mounts and core support mounts.

[Getter-Done]

Every thing that was mentioned above needs to be double checked

Also just for the odd chance

Check the Frame around the (steering box)

If it is cracked or Broken ?????









.

[4u2nv]

I have seen it happen , check your tranny mount , if it's gone bad there is enough flex there to shift up through even if the engine mounts are fine.

[otterby]

Looking closer at the motor mounts I think that is the problem. They are difficult to see but the rubber looks deteriorated. I'm going to go ahead and replace the motor mounts and transmission mount since they are all probably original to the pickup. Does anyone have experience with the polyurethane mounts? I'm looking at the ones from Energy Suspension. They cost a little more but look like a much better mount.

[Pontiac1976]

I like and have used Energy Suspension. The Trans mount I all was use rubber there. Just to give a little buffer on the trans case. The Motor mount you have to use the old clam shell from the GM drill the two rivets out put in the polyurethane mounts and zip tie or rivet together.

Every thing that was mentioned above needs to be double checked

Also just for the odd chance

Check the Frame around the (steering box)

If it is cracked or Broken ?????

All good but just make sure the shroud sitting in the bottom clip or bolt in the right spot. this is the only one I did not see.( since the motor was changed)

[otterby]

So this thing is really throwing me for a loop. Replaced the motor mounts and transmission mount and there was no improvement. The frame is good around the steering box. The front end is square. Measuring off the bumper it actually could move a little in the opposite direction I need to get it away from the fan, so that’s not it. There isn’t any adjustment with the shroud. When I measure across the shroud opening to the center of the water pump shaft it’s an 1/2 inch off. So either the radiator support needs to move 1/2” to the drivers side or the motor needs to move 1/2” to the passenger side. What am I missing?

[4u2nv]

OK last idea I got , replace the fan !!!!!! Is it a flex fan ???

[otterby]

Originally Posted by 4u2nv

OK last idea I got , replace the fan !!!!!! Is it a flex fan ???

Unfortunately I think that's where I'm at. I'll probably just replace the fan with an electric setup. The fan in it now is stock which is why this is driving me nuts. Something is out of whack but I just can't figure out where.

[Pontiac1976]

Did you check the bottom of the shroud to make sure the spring clip
that it slide in to holding it in the right place or if it has the clip that the bolt mounts to is not broken,( this means the top clips bolt in clips ) or in both cases the pop out of place. or do you have the clutch fan on it or the clutch is wore out. And you should be able to see that by motor running looking at it. only one more thing some hit the front of your truck pushed the rad support in a little. other thing but think you would have seen it water pump shaft, one fan blade bent, rad support rusted drop down,

[Pontiac1976]

If your thinking electric fan setup, this electric might a nice up grade for your 502 should take care of all your cooling needs. https://bowtieguy.proboards.com/thre...l-electric-fan

[otterby]

Originally Posted by Pontiac1976

If your thinking electric fan setup, this electric might a nice up grade for your 502 should take care of all your cooling needs. https://bowtieguy.proboards.com/thre...l-electric-fan

Thanks! I've actually got a two fan assembly from a Windstar laying around so I'm gonna try it first. The truck has a MSD Atomic so I can control two fans with it.

[Dead Parrot]

Odd thought. The K frames are noted for cracking where the steering box bolts on. The core support is forward of the steering box. If your frame is cracked at the box, the nose of the truck might be enough out of position to cause the fan to shroud contact.

[otterby]

Originally Posted by Dead Parrot

Odd thought. The K frames are noted for cracking where the steering box bolts on. The core support is forward of the steering box. If your frame is cracked at the box, the nose of the truck might be enough out of position to cause the fan to shroud contact.

Double checked the frame around the steering box and its good. I cant find a single thing wrong so I'm going electric. Gonna do a set of fans from a 2000 Ford Windstar and it looks like they'll fit nicely. Has anyone else on here used these fans in their squarebody?

[Pontiac1976]

about 12-15 year ago those where the good dual fan worked well seen a few at the drags. If your rad is the smaller style rad small block fit ok. If you have the big block large rad 73-80 and 81-87 tall but not as wide it may not fit the rad as nice. To get best cooling you may need to make a shroud adapter funnel air throw hole rad. https://bowtieguy.proboards.com/thre...nting-brackets This show the break down of the rads in LMC