20 hp Honda eng.

[russau]

I had one of these running awhile back that I got from my brother and wanted to buy / install a BIG pump (500 GPM)on it and was wondering if this would be a quick sell. well at that time I really didn't have to money to buy the pump from Keene. I ended up selling that engine. Now I have another chance of getting another Honda engine and was wondering if I should or not . The Keene 500 GPM pump is $650. alone and not including shipping. Id love to have this on a pontoon boat for some un-named river! I need to get a coin to toss to see if itll be heads or tails!

[micropedes1]

Russ, I have done what you are contemplating. You will find that the shaft is too short. I have added a threaded extension, but it is a pain to get it true to the existing shaft. Better I think to upgrade to engine with threaded shaft.

[LipCa]

Do they even offer a 20 hp with a threaded shaft?

[russau]

Well the auction is next week and IF I can get that engine cheap enough I may try to do this. BUT I don't have ANY need for it or the strength to move it around anymore! I am thinking of an investment! How attractive of a deal would this be for someone wanting to build something ?? Now "if" I had a pontoon boat it would be different for me!

[micropedes1]

Russ, I took a piece of round 1" stock and threaded it on my lathe (1x20NF, I think). Then center drilled it and tapped it 7/16 x 20NF. Then I parted it off in approximately 1 inch pieces. Then I threaded a 7/16 tapered head cap screw thru the parted piece and into the end of the output shaft and checked with impeller mounted to make sure that the distance to the engine face was the same all the way around. Once certain that the impeller was running true, I tapered the contact between the threaded piece and the shaft and welded them together in stages, making sure that I did not get the shaft too hot and ruin the seal in the housing. Assembly of close-attached pump might require washers to space the housing out far enough to obtain the correct clearance and to compress the seal spring on the pump. The only other alternative is to grind the end of the now-threaded shaft so that the impeller is a proper fit.

Lots of work unless you have the right tools. Lots of headaches even with the right tools. There is enough clearance between the large 6 inch impeller and the volute on the big Keene pump so that you can run with .006-.008 inch of wobble in the impeller if you do not get it quite right. Rough on the motor's bearings though.

[russau]

Thanks for the tip Glen!

[dickb]

I would think you could machine a stub shaft for the pump and turn it into a pedestal pump and drive it with a flex coupling. Way easier mechanics and serviceable.

Dickb

[Hoser John]

I really like the 18hp Vanguard series with the highly modified remachined high dome pump made especially for that engine. No modifications/lovejoy connectors needed- John