Excessive dust from new belts

[slash007]

I just installed six new pumps and new belts on each. So far after two weeks I noticed that there is a large amount of black dust coming from the belts. The sides next to the pumps are almost covered in black dust. Is that normal for new belts? If not, what is the likely cause? I am using B44 belts I got from Kleen Rite. I didn't want to change anything until I had an idea of the cause and if I should be worried that it will continue and the belts will break soon. Thanks.

 

[MEP001]

It's not normal - the belt is too loose.

 

[slash007]

Is there a rule to how tight the belts should be? They seemed ok, but I wasn't sure how tight to go.

 

[I.B. Washincars]

I agree with MEP. On most equipment it's pretty hard to tighten the belt by yourself. I usually get it as tight as I can by hand, then snug up a bolt or two. I then roll the belt off the pulley, loosen the pump back up, scoot it forward 1/8" (maybe a bit more), tighten it back down, and then roll the belt back on the same way I rolled it off. As long as it's tight enough it's not terribly critical. I've been doing it this way for decades and have never damaged a pump or motor doing this.

 

[HCW]

Is it happening on all six? Get a straight edge and make sure pulleys are aligned. Possibly cheap belts. I use gates or ac delco.

 

[MEP001]

Depends on the brand on how tight to get them from new, some will "set in" and have to be re-tightened in a week or two, some don't stretch at all. I've been using the Gates poly-cog which don't seem to stretch much, the Dayton from Grainger are so bad that if you tighten them where there's almost no deflection at all they'll still be loose enough to slip after a month or so.

When there's not a motor adjuster to make it easier, I like using a crowbar prying against a bolt on the pulley side of the pump and pushing on the crankcase near the bearing. That makes it easier because you can pull with one hand and reach under the stand and tighten the nut with the other while the crowbar keeps the bolt head from turning.

You can't really overtighten the belt without a tensioner, so just get it as tight as you possibly can, or roll the belt on as I.B. suggested. I don't like doing this with shorter length B-belts, but wear heavy leather gloves and turn the belt onto the motor pulley while you turn the pump pulley and you won't get hurt if you're careful. If you have a tensioner, you should get maybe 1/2" deflection with a B44 belt. Again, it's hard to overtighten it - you won't hurt the pump or motor bearings.

 

[washnvac]

Are both pulleys designed for B size belts? Could be one or both pulleys require a more narrow belt.

 

[slash007]

I'm pretty sure both the motor and pump are designed for the B size belts, but I'll double check. I know the pump is for sure. I looked at them and it seems that they might slightly be misaligned (motor and pump) but I don't really have room to move one or the other much, so I'll put a straight edge and see what I can do. All pumps and belts were new, I might have to re-tighten them as well. I appreciate all of the suggestions and will try some of them tomorrow. Don't know why I bought the KR belts, I used to always use the cog type. Luckily belts are pretty cheap either way.

 

[2Biz]

You can easily make your own belt tensioner out of a turnbuckle from the hardware store and two pieces of 1/2" plywood. Get a turnbuckle that has looped ends so you can bolt the loops to the pieces of plywood. You'll have to measure and cut the plywood accordingly. Cut a "Vee" in the ends of the plywood so they fit in each pulley. It sure helps to hold tension while aligning with a straight edge. It worked for me when I put all new belts on 6 years ago. Haven't touched them since!