Bertram31.com General Bulletin Board

Re: shafts and props

Posted By: Randy Cootes
Date: Friday, 11 March 2005, at 12:34 p.m.

In Response To: Re: shafts and props (Rich H)

Carl,
We did a GM 453 (110HP) to Cummins 6BTA (300HP) diesel-to-diesel conversion and upgraded the shafts from 1-3/8" to 1-1/2" AQ22 on a 1972 31 FBC. The 6BTA's fit perfectly coupled with a Z-F IRM220A gear with little to no mods. We did have to make custom wet exhaust elbows from Monel 400 and a custom FG wet exhaust system on the port engine to clear engine boxes, but made no mods to bulkheads or major components. Swinging a 20"x23", 4-blade you'll be looking at 34 kts WOT and a 26 knot cruise while averaging 1.5 nm/gal; not too bad compared to the old 17 kt WOT with the old GMs.
Good luck,
Randy

Messages In This Thread

shafts and props
Carl -- Thursday, 10 March 2005, at 10:51 p.m.

Re: shafts and props
Capt Patrick McCrary -- Friday, 11 March 2005, at 1:36 a.m.

Re: shafts and props
phil -- Friday, 11 March 2005, at 7:50 a.m.

Re: shafts and props
craigmac -- Friday, 11 March 2005, at 9:15 a.m.

Re: shafts and props
Rich H -- Friday, 11 March 2005, at 12:05 p.m.

Re: shafts and props
Randy Cootes -- Friday, 11 March 2005, at 12:34 p.m.

Re: shafts and props
carl -- Friday, 11 March 2005, at 12:45 p.m.