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I need a belt for my Borgeson PS pump.

Whats the proper way to measure for belt length?
 

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If you already have a worn belt and need to replace it, use any method shown here..

Otherwise, as suggested run a flexible tape (not string) around your pulleys.. remembering, that belts are measured on the Outside Diameter.

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If you already have a worn belt and need to replace it, use any method shown here..

Otherwise, as suggested run a flexible tape (not string) around your pulleys.. remembering, that belts are measured on the Outside Diameter.

Sent from my SM-G950F using Tapatalk
If you have the old belt, bring it with you to the store :)
If you don't, then best bet is the cloth ruler.
 

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I use a piece of twine and scrap fuel line hose. Make a "noose" on one end of the twine. Thread the scrap pieces of fuel line hose onto the twine then loop it around the pulleys so the fuel line sits in between the sheaves. Thread the "free end" through the "noose", pull to get it taut and mark the twine where it exits the "noose" with a Sharpie, masking tape, etc. Lay the twine out lengthwise to measure and you'll be damn close.
 

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I'd use a piece of cotton (or whatever) clothesline rope. Just wrap it around the pulleys and, when the extra length meets the cut end, just mark it and measure it. Or, if you have an old belt that is too big, cut it and do the same thing. Then you can take it to any parts house and measure it against a new belt.
 

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Important to note that you should do your measuring with your accessory closer to the crank pulley in its adjustment range, rather than at the far end of its range - or you'll have trouble tightening the belts correctly.

When I was building my car, I just used a piece of string and added an inch to get me in the ballpark, then played the "How many times can I go to NAPA in one day" game and traded in belts until I got one that was perfect. Now I just save the part numbers since I know my current belts work.
 
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67 coupe, 69 Sportsroof, 86 hatchback
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I don't know about "proper" but I have a small selection of old belts. I get one that is too long and cut it. Loosen the accessory as much as possible and wrap the belt. Tighten the belt as much as possible and clamp the cut ends with a pair of vice grips and adjust the accessory all the way out. Back in again and try to shorten the belt a smidge if I can for a more precise fit. Take my clamped belt to the parts store, ignored the funny looks and comments and say "gimme one of these, but just a tad shorter". DIY measuring always seems to get you a belt that's a bit long. This method works a lot better with serpentine belts so you don't have to ask for a shorter one with those.
 

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Attached are several pictures of what I have used since I picked it up at a Swap Meet in the early 80's. This is the "proper" way. However, before that, I used two nails, one at each end of the belt, driven into a 2 x 6, and then the OD of the belt measured with a cloth tape.

Bob

Autolite V-Belt Ruler (2) -.JPG
Autolite V-Belt Ruler (3).JPG
Autolite V-Belt Ruler (4).JPG
Autolite V-Belt Ruler (5).JPG
 
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