help installing small ribbed belt

[MstrCarpenter]

Recently had a small Husky air compressor given to me. previous owner thought an air line was disconnected inside because it ran but didn't pump air. Spent about 10 minutes to pop off the cosmetic housing to reveal a broken belt. Cool! That's an easy fix. Even has a part number on the original belt; "PJ307". Got the replacement "4PJ307", *(I assume the 4 relates to the 4 ribs.) and I've just spent over an hour trying to get that belt on. AARG! it seems like the belt is too small but the original appears to have been smaller. There's a pulley on the crankshaft about 3.5"dia. and one about .75" on the motor shaft with only about .25" between them. I don't see any way to move the shafts closer together as the bearings for both are in the same casting and I can't roll the belt around the larger pulley without it coming off the small one. Both belts have little to no stretch but somehow, someone got it on. Any tricks or advice? I'd rather throw the whole thing in the dumpster than spend another hour on it.

[barryvabeach]

Recently had a small Husky air compressor given to me. previous owner thought an air line was disconnected inside because it ran but didn't pump air. Spent about 10 minutes to pop off the cosmetic housing to reveal a broken belt. Cool! That's an easy fix. Even has a part number on the original belt; "PJ307". Got the replacement "4PJ307", *(I assume the 4 relates to the 4 ribs.) and I've just spent over an hour trying to get that belt on. AARG! it seems like the belt is too small but the original appears to have been smaller. There's a pulley on the crankshaft about 3.5"dia. and one about .75" on the motor shaft with only about .25" between them. I don't see any way to move the shafts closer together as the bearings for both are in the same casting and I can't roll the belt around the larger pulley without it coming off the small one. Both belts have little to no stretch but somehow, someone got it on. Any tricks or advice? I'd rather throw the whole thing in the dumpster than spend another hour on it.

Have you tried soaking it in boiling water for a few minutes, then using gloves, see if that gives enough stretch.  We use that to put bandsaw tires on and it can help.

[MstrCarpenter]

Have you tried soaking it in boiling water for a few minutes, then using gloves, see if that gives enough stretch.  We use that to put bandsaw tires on and it can help.

Barry, I thought about that but didn't have a quick easy way to boil water in the shop. I didn't dwell on it because the belt(s) are reinforced. I did try to stretch it over a small hobby vice by opening the jaws and didn't gain anything. I did do a search for "installing a small ribbed belt" and there were several videos on how to install the same belt on similar compressors. Glad to see that I wasn't the only one with this problem. I had the right idea but starting with the belt on the bottom of the pulleys is supposed to be easier to prevent it from rolling off the smaller drive pulley. We'll see if it works.

[barryvabeach]

Barry, I thought about that but didn't have a quick easy way to boil water in the shop. I didn't dwell on it because the belt(s) are reinforced. I did try to stretch it over a small hobby vice by opening the jaws and didn't gain anything. I did do a search for "installing a small ribbed belt" and there were several videos on how to install the same belt on similar compressors. Glad to see that I wasn't the only one with this problem. I had the right idea but starting with the belt on the bottom of the pulleys is supposed to be easier to prevent it from rolling off the smaller drive pulley. We'll see if it works.

Good luck, and if that works, you might want to post back with the concept.  Wonder how they do it at the factory where the assemble the compressors.

[Cooler]

The old refrain:  Google is your friend.  

This video gives instructions on the replacement of that belt.  This guy must have struggled with it before he figured it out.

https://www.youtube.com/watch?v=-Bb2LdU-nPE

[barryvabeach]

The old refrain:  Google is your friend.  

This video gives instructions on the replacement of that belt.  This guy must have struggled with it before he figured it out.

https://www.youtube.com/watch?v=-Bb2LdU-nPE

Nice post - without using the screwdriver, I don't think that would work - wonder how long it took to figure that out.

[MstrCarpenter]

That was one of the better ones I watched. I put the belt on the pulleys, leaving the "un-mounted" portion off the back of the large one. Then I put a round shaft screwdriver between the belt and motor to keep it on the small pulley as I rotated the large one. I needed both hands to hold a rod in an opening while I used a lever to rotate the large pulley. No way could I turn it by hand. It went right on. Less than two minutes. Can't believe I spent an hour trying from the front side, thinking there has to be an easier way, but still didn't consider trying from the back! Anyway, it runs pretty quickly right up to 160 P.S.I. 'til the safety release trips. Now I have to figure out the pressure switch. They're cheap enough to only be sold in two packs. I'll clean what I have before I order them.

B.T.W. There's a Bostitch oil-less compressor in my shop that needs brushes. The cast alum. body is a little beefier, but all the parts look identical to the cheap Husky. It's running the same belt number, the heads are the same and the piston ring looks original. Bostitch's "new piston and ring assembly" makes it the same as the Husky though.

[wood2woodknot]

Although Google seems to have solved the problem, I wonder if a thin coat of dish detergent on a section of the belt ribs might give enough "slip" to get things together. Maybe this is way out there, but it has come to my rescue a number of times in the past getting things to mate up. The soap will dry without leaving an oily surface.

[MstrCarpenter]

Although Google seems to have solved the problem, I wonder if a thin coat of dish detergent on a section of the belt ribs might give enough "slip" to get things together. Maybe this is way out there, but it has come to my rescue a number of times in the past getting things to mate up. The soap will dry without leaving an oily surface.

I have to admit I did eyeball the can of PB Blaster a few times. I didn't think of soap though. I know I wasn't at 100% mentally, but oh boy, was I getting pissed!