# Briggs lawn mower blade height



## lanche (Jun 8, 2005)

I'm building a mower out of some spare parts I have. What I used is a 7 hp briggs off of a pressure washer and put it on an old deck. The problem is the crank is shorter so Im looking for a longer blade hub. Does anybody know if they make different lengths or are they all the same 1.25 in


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## paulr44 (Oct 14, 2008)

Standard crank length for mower engines for years was 3-5/32. Any hub extension that you could find would probably be not designed for such use, and of a metal that would probably fracture easily upon a blade impact given the extension length and relative shock forces involved with a blade impact. As no one had responded, it's likely because there's a safety issue here preventing a helpful response.

Unless you had a machine shop make an adequate extension that would be deemed sound given the potential forces involved with blade impact, you're putting yourself and anyone in the vicinity at risk with anything less.

Most blade hubs extend beyond the crank end about 1/4" or so. Given that, perhaps you can understand why as hubs are usually a powered (sintered) metal or aluminum.

In short, as a professional I can't condone it, and wouldn't advise it. Change the crankshaft, or get a different engine.


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## lanche (Jun 8, 2005)

I can appreciate and understand any safety issues and I would never build something I thought would be unsafe. The reason I'm asking is the tecumseh blade hub was about an inch longer than the briggs and that's really all I need but yes it has to be safe.. thank you..


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## paulr44 (Oct 14, 2008)

Don't know of any crank extensions off hand for use with a mower. Only thing I can tell you that may help is that Sensation used to put a crankshaft support plate under the deck to help prevent bent cranks...if you do use an extension their support plate or similar should help the safety factor. Their plate mounted with the engine mounting bolts, and was basically a saucer shape design made of aluminum.


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