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This is a dumb question but I’m new to the business

Sakran

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I’m trying to change a belt a
On a 310 cat pump. I can never get it right enough though. I pull has hard as I can then tighten the bolts in the back it’s not super loose but it’s not where it want it to be. Is there a technique to do it correctly. I saw one guy use a come alone but the way these are positioned it’s not possible.
 

washnvac

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Remove the belt, then pull the pump forward a bit. Tighten bolts, then spin belt back on. (Be sure breaker is off before you do this, though. Do not want you to lose a finger)

I never loosen bolts when putting belts on. You just spin old one(s) off, and spin new one on.
 

I.B. Washincars

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Remove the belt, then pull the pump forward a bit. Tighten bolts, then spin belt back on. (Be sure breaker is off before you do this, though. Do not want you to lose a finger)

I never loosen bolts when putting belts on. You just spin old one(s) off, and spin new one on.
I did basically the same. If I had the pump loose for some reason, I would pull it as tight as I could by hand and tighten a bolt or two. I would then roll the belt off, move the pump forward about 1/8" and roll the belt back on. This was usually good, but if you don't feel it's tight enough, play with the amount a little bit until you're satisfied. It's not very critical.
 

MEP001

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I’m trying to change a belt a
On a 310 cat pump. I can never get it right enough though. I pull has hard as I can then tighten the bolts in the back it’s not super loose but it’s not where it want it to be. Is there a technique to do it correctly. I saw one guy use a come alone but the way these are positioned it’s not possible.
Get one of these:


Most of the time I can hook the claw under the manifold and the head will reach down to the front of the stand. I can push down on the hammer with one head and tighten the front bolts with the other.

Another option is finding a prybar with the right bend to it where you can push back against the pump near the pulley using the front bolt on that side to pry against. It works better because the pry bar will keep the head of the bolt from turning.

There's a pulley spreader tool you can buy, but I haven't found one that's sturdy enough to get belts tight enough in this application.

IMO if you can get the belt on by slipping it over the pulleys, you're using the wrong belt. An A-width belt will go on this way, a B-width will not, and you really should be using a B-width if you want them to last. The right belt will last at least ten years.
 

edredtop

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Too tight can be fatal for bearings.

Way back before tensioners, I was changing an automotive belt on a power steering unit and my old man asked me:
"The next time you do this job, do you want to replace a bearing or a belt?"
The obvious answer is a belt.

Bearing replacements are a time consuming job compared to a belt replacement.
A tad too loose is far better than a tad too tight. Don't overdo it..
 

MEP001

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Too tight can be fatal for bearings.

Way back before tensioners, I was changing an automotive belt on a power steering unit and my old man asked me:
"The next time you do this job, do you want to replace a bearing or a belt?"
The obvious answer is a belt.

Bearing replacements are a time consuming job compared to a belt replacement.
A tad too loose is far better than a tad too tight. Don't overdo it..
The bearings on car wash pumps and motors can handle being so tight that the belt will "twang." The belt will last longer if it's tight because slipping wears it out quickly. Cars are completely different - that's why nearly all of them now have tensioners that you don't adjust.
 

MEP001

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I never had any trouble rolling a B belt on and off. Mine were on Mark VII system and were relatively long (B-51 IIRC), which probably helped.
Mine are B-38. There's no way I'm getting them on with them as tight as I like them. They usually stretch anyway, so putting a new belt on not quite tight enough will have it slipping in a month.
 
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