I Rebuilt my fan pulley on my 26. I put new bushings, an new bolt, a new felt washer and retainer. Problem is that when the fan turns the bolt turns, if you tighten the nut too tight it won,t turn at all. if you loosen it the bolt comes loose their is no place to put a cotter key. I bought all the parts from Langs. Do I have to ream the bushings,the old bushings were not that bad. I have grease it. I am stumped.
The hub should turn freely and have some end play on the shaft. Also the 26-27 fan does not use a cotter pin, if you have a hole in the shaft for a cotter pin you must have the wrong shaft. I rebuilt mine last summer and the aluminum pulley did not hold the new bushing tight, the bushing ended up spinning on the hub. I bought a different aluminum hub and rebuilt it with roller bearings and added a shaft seal.
There is a step in the shaft and when you tighten the nut that step is all the way back. The shaft is then tight and the fan should be free to spin on the shaft. Maybe the bushings need to be faced?
I have never seen the two steel sleeves you have pictured. Also, the original bushings are longer than what you have pictured. Do I see an O ring? Originally they used a felt washer, and a steel cupped shaped washer at the end.
I cut the length of the bushings down and opened up the ID to use them only as a trust surface. The "steel sleeves" are needle bearings, and the "O-ring is a high speed shaft seal. The MTFCA engine book shows how to add needle bearings to a fan hub, but the bearings are too long to fit in a 26-27 fan hub. I improved the idea by finding shorter needle bearings and I added an oil seal. The seal is made by SKF for a .625" shaft, and a .812" bore, the part number is 6105. The needle bearings are Torrington B108OH.
Are you sure those Torrington bearings aren't part number BH1008? "H" for heavy, 10 for 10/16" shaft (5/8") and 08 for 8/16" wide (1/2")
I will double check the part number on the box, but as I remember B is for roller bearing, 10 is for 10/16th's shaft dia, 8 is for 8/16ths length, and OH is for oil hole.
Could be Jeff. I've been wrong WAY more than once.
B-108OH it is - I looked it up on the internet catalog.
The Torrington B-108 (no oil holes) should work fine also since the oil holes in the shell of the B-108OH (not visible in the picture above) will be covered by the hub when installed.
My apologies for interjecting my confusion.
I agree. Seems to me the MTFCA engine book describing how to do this had a bearing with an oil hole. But clearly the oil hole will not do anything and so it is a matter of what bearing is readily available. For that matter, a B106 or B106OH would probably work OK too.
I agree that the 3/8" wide bearing would probably be OK, but only if the shaft that they ride on is hard enough and the belt is kept sufficiently loose.
Since the hardness of the shaft is somewhat immaterial when using journal bearings (bushings), I rather doubt it is really hard enough for very long life using rolling-element bearings so the longer the rollers (needles) are, the better.
Agree, that is why I went with the 1/2" long bearings. For the rear bushing I opened up the ID so it will not ride on the shaft since it is not running in oil due to the shaft seal. As I think about it now I wounder if I even needed that rear thrust surface. I have never worn out a felt seal so I probably would not wear out the aluminum hub either.