Farmall Cub Radiator Replacement

R

RunningRed

Well-known member
Hey fellas, I finally got around to working on the Cub to get it setup for winter. I got the old radiator off without breaking any bolts. They weren't very tight at all, barely hand tight I'd say. Problem is I have 5 short bolts and the rest are longer. Where do the short ones go? Should I reuse the old bolts even though they appear to be in good shape? I cleaned up the holes with a tap and ran a die over all of the bolts. Also is there anything else I need to check for replacement while I have the front torn down? There is a little bit of end play and wobble from the fan but I don't know if there is a bearing or bushing in there to replace.
 

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I've replaced old bolts with stainless to save the next owner any trouble, TM sells a set. They should all be the same length to hold down the radiator supports and the front and back strips. I'd guess that the shorter ones were replacements. You should have eighteen that are 7/8" long.
 
There's nothing wrong with reusing the old bolts, just make sure the short ones are replaced with some the correct length. Don't over tighten the bolts, that can smash the gasket and deform the flange on the radiator.
 
RunningRed said:
Also is there anything else I need to check for replacement while I have the front torn down?
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Hi,
Check the fan belt tension, and the generator, or alternator belt tension.
The fan belt looks loose in your picture, but it's hard to know in a picture.
Over the years they have made belts for the fan with or without cogs. Either one works.
Below is a page from the 1950 Cub operator's manual telling how to check and tighten the belts.
Do Not turn the nut at the rear end of the fan shaft, it can break the casting that holds the fan hub.
Turn with a wrench on the 6 sided place just to the rear of the gen pulley.
Hold the nut at the rear to keep it from turning, if needed.
If the belts look old, it's a good time to replace them.
https://farmallcub.club/rudi/farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Cub Owner's Manuals/McCormick Farmall Cub Owner's Manual 1950/Page 27.jpg

Below is a listing at TM Tractor Parts for a new fan belt.
Don't buy too short a fan belt, it can make the gen or alt pulley on the fan hub too low.
The new fan belts I have bought at Case IH make the fan shaft a little under half way up the slot that holds the fan. They don't use the lower half of the slot, except to lower the hub down, to loosen or replace the belt.
I don't know if this belt is the same length as the Case IH belt, I would suppose it is.

The gen or alt belt should be a length that the bolt isn't out near the end of the adjuster, so the belt can be tightened in the future, without removing the hood, and having to replace the belt then.

I would remove the bolts, and use a long straight edge on the housing where the radiator goes, and be sure it is flat.
They have said on here the housing can be pushed up in that area from the coolant freezing.
 
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RunningRed said:
There is a little bit of end play and wobble from the fan but I don't know if there is a bearing or bushing in there to replace.
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The fan shouldn't have any side to side play in the bearing. It sounds like it is worn some.
If the hub is the original style it doesn't have a regular bearing, it is a hub with a hole, that goes on a shaft. The shaft and bearing are about 3" long.
I would oil the fan hub, if you haven't lately. If it is low on oil it can make the bearing wear, or the fan can seize.
Below is a page from the 1950 Cub owner's manual telling how to oil it.
The hub uses oil, light motor oil is good.
I put new oil in a clean pump oil can and squirt it into the hub.
https://farmallcub.club/rudi/farmal...k Farmall Cub Owner's Manual 1950/Page 28.jpg

If you are removing the belts, it's a good time to remove the fan and hub assembly, and you can drain most of the old oil out of it. Just hold it with the rear of the hub down, and the oil should run out. The hub has no oil seal at the rear. If you catch the oil in a clean can, you can see what was in it.
 
Glen said:
The fan shouldn't have any side to side play in the bearing. It sounds like it is worn some.
If the hub is the original style it doesn't have a regular bearing, it is a hub with a hole, that goes on a shaft. The shaft and bearing are about 3" long.
I would oil the fan hub, if you haven't lately. If it is low on oil it can make the bearing wear, or the fan can seize.
Below is a page from the 1950 Cub owner's manual telling how to oil it.
The hub uses oil, light motor oil is good.
I put new oil in a clean pump oil can and squirt it into the hub.
https://farmallcub.club/rudi/farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Cub Owner's Manuals/McCormick Farmall Cub Owner's Manual 1950/Page 28.jpg

If you are removing the belts, it's a good time to remove the fan and hub assembly, and you can drain most of the old oil out of it. Just hold it with the rear of the hub down, and the oil should run out. The hub has no oil seal at the rear. If you catch the oil in a clean can, you can see what was in it.
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The fan when it's cooled has just a little wobble but I was thinking last time I ran it when the tractor was up to temperature, I was messing around with the tractor when I parked it and I remember grabbing one of the fan blades and it wobbled a lot. I wonder if I could machine up a new shaft and bushing for it? I don't know if I can because I have never seen it off the tractor.
 
Barnyard said:
How can you tell?
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On my computer the belt looks like is bulging out to the sides from the crankshaft pulley, it's so close to the pulley it's hard to know. It might not be loose, if it's just the picture making it look that way.
I think if the belt is snug it goes straight up from the pulley.
 
RunningRed said:
I wonder if I could machine up a new shaft and bushing for it? I don't know if I can because I have never seen it off the tractor.
Click to expand...
They make new replacement fan hub assemblies nowadays, with sealed bearings.
There is a picture of the Bearing, they call it in the manual page I posted at post 9 above. The Bearing is also a hub like piece.
I think the shaft has to have a spiral cut in it, for oil to go to the inside of the bearing.
Below is a page from the Cub parts manual showing the fan hub.

Below is a picture of part of the assembly.
 

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To clean the material in the air cleaner, when the air cleaner is off the engine, cover the outlet for the pipe to the carburetor, turn the air cleaner upside down, with the oil cup off, and pour in a cup or so of kerosene. Put the oil cup on, with it empty, and shake the air cleaner in different positions.
Remove the cup and dump out the kerosene, if you dump it in a clean drain pan you can see what was in it.
If it is really dirty, repeat using the kerosene.
Remove the cover from the carb pipe connection when done.
 
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