Lawnmower engine shaft sizes

[DLausche]

I need to replace the engine on my walk-behind lawnmower. I'm seeing some places describe 1" shaft and others describe a 25mm shaft. These appear to me to be the same diameter (or very close). Are the blade adapters & belt pulleys sized 25mm vs. 1" interchangeable or not? Thanks



-Deon

 

[CSnyder]

Deon, what kind of mower do you have?



Chris

 

[DLausche]

It's a Scott's 21" mower with swivel front wheels. Cheaper to replace the engine than the whole mower. It is made by Ariens in Wisconsin and I really like this mower.



-Deon

 

[KBennett]

I don't know the answer to your question but 1 inch is 25. 4mm, . 4mm=. 016" so it would be pretty close. They may just be rounding to 25mm.

 

[DLausche]

I found the answer to my question yesterday and figured that since I asked the question here I should probably share the answer as well...



25mm and 1" are definitely different sizes and the blade adapters and pulleys are likely not interchangeable. The answer I received was in response to a question to a vendor of Briggs & Stratton engines. He indicated they (25mm & 1") are indeed different sizes. Most small B&S engines (i. e. for a lawnmower, etc. ) have either a 7/8" or 25mm shaft size. However, engines 8HP and above have a 1" shaft size.



-Deon

 

[KBennett]

Thanks for clarifying

 

[Dieselnut59]

Does your mower use a horizontal shaft engine or a vertical shaft type? I want to re-power a lawnmower similar to the type you describe. I have a brand new Yanmar 6. 5 horsepower horizontal shaft air cooled diesel engine that I would LOVE to use on a good lawnmower.

 

[DLausche]

Does your mower use a horizontal shaft engine or a vertical shaft type? I want to re-power a lawnmower similar to the type you describe. I have a brand new Yanmar 6. 5 horsepower horizontal shaft air cooled diesel engine that I would LOVE to use on a good lawnmower.

Mine is a vertical shaft mower - the common kind of walk behind type mower. A Yanmar Diesel would be way cool on a mower but I don't know of any type of small mower that would work with a horiz. shaft engine. I don't have a large enough yard to warrant any type of serious lawn cutting machine.



Let me know if all else fails and you can't find a use that there Yanmar you have. I could take it off your hands and put it to good use on my Snowblower here.



-Deon