How To Convert A 3/4″ Crankshaft To 1″ On A Small Engine

In this video I show you how to easily convert a 3/4″ crankshaft to a 1″ shaft. This is a convenient way to re-power equipment that requires a 1″ shaft.

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40 thoughts on “How To Convert A 3/4″ Crankshaft To 1″ On A Small Engine

  1. Hi there! I just swapped a 22hp b&s with a 20hp b&s on riding lawn mower turns out the 22hp had a 1" 3/8 and the 22 has 1" shaft can i find an adopter for that where i can use the same clutch and drive pulley?

  2. Awesome stuff. I need one of those. I just bought a brand new Tecumseh HMSK 100 and the shaft is 3/4 " my pulley is 1"

  3. Hello don my name is Dan and I'm looking for. A rebuild kit for a tecumseh snow king engine as it broke a valve from running it to hard and I can't seem to find one in the internet the model is lh358sa
    thank you,

  4. LOL $55.00 each… Hell Guys you can get these shaft adapter at "The Big Bearing Store" Online for $7.98 each all Day!

  5. Hi Donny , want to put a 15/16 blade adapter/pully on a 7/8 crankshaft thinking of installing 1/32 shim material inside adapter and slide it over the crank, locktight then drill for offset allen screws (3). What do you think .

  6. Ideally I'd like to have the slot for the inner groove and outer groove be 180 deg apart. That big open slot seems like it would be a weak spot.

  7. Nice video. Can you go from 3/4 in. to 7/8? Have seen some kits on ebay for doing that but it would be nice to get more than one source.

  8. Is there a good way to extend the crankshaft a couple inch's extra? Do u carry any products that do? Any good advice?

  9. Are these adapters available to convert a tapered generator engine shaft to a straight shaft? I just junked a running 13 HP Honda due to a bad stator which I was quoted $1,000 to replace!!!

  10. do you have a part number for that shaft or who (company got it from) i work for midwest power equitment and have to do that exact change thanks -nick

  11. Dony, I have a Briggs and Stratton with a 1" shaft. It's iut of a Sears suburban, I want to order an original pulley as I don't have one. The catch, The pulleys are 1 1/8 inch.. What do I do? I can't find an adaptor

  12. Hello Donny. You provide excellent info and I appreciate it. I have an MTD Chipper/Shredder 242A645. It has a Briggs 5HP engine and the motor snapped the connecting rod. I tried to fix but the cylinder has deep scratches. I had bought a Harbor Freight 6.5HP motor to put on it and the shaft was quite a bit smaller. This video has me hopeful that I can adapt it to fit. My question is since the shaft diameter is smaller, do you think it would snap from the load of the heavy flywheel and the debris being put into it? I understand your just giving advise and I wont hold you responsible, but you have way more experience and knowledge to make that educated guess.
    Thanks in Advance,

  13. Very much enjoy all your videos! I have the opposite problem, I need to fit a 3/4" pulley on a 1" shaft.  What kind of sleeve can I buy to make the crankshaft smaller?  ;^)

  14. Great vid – thanks
    Question: I need to convert a 3/4 by 1 inch shaft to a 1 inch by 3 5/32 inch shaft. Is there a converter sleeve?

  15. J'ai la même poulie sur un moteur Briggs and Stratton  8 hp d'une souffleuse Toro 826 ( qui a manqué d'huile ) et mon problème est double: first, je n'arrive pas à sortir cette poulie, j'ai essayé avec un puller,  j'ai chauffé, je ne sais plus comment faire! si vous avez un truc infaillible, j'aimerais bien le connaître. Second, j'ai un bon moteur de pressure washer 206 cc Brig. Strat.  dont j'aimerais savoir si je peux la mettre su la souffleuse Toro 826?

  16. I don't think I have seen those sleeves before. Nice that you put a SnoKing on it and not a Chinese clone. Keeps it looking more like an original Ariens. They sure throw snow.

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