200 more hp (and a shit load of torque) should get you something!
Please post pics of each step along the way. Are you not sure its going to fit?
2.5 gearing and will be going with 1-3/4" shaft with new wet tube,
couple of questions Larry was thinking about going dripless on the packing do you think I will need a cutlass at each end or the tube? and my feed water outlet for the old tube came from my exhaust will that be sufficient it has 4" exhaust and plenty of water to keep the old one cool
NO! only one cutlass bearing at the tail end or wheel end of the shaft. Cutlass bearing that close to the transmission is not a good idea. The shaft will be held in a mush to tight of tolerance. Ailment will be very hard. In addition with the bearing that close to the gear the shaft starts to work. The process is call kneeing the metal. Over time with the shaft being kneed by the front bear it will break at the coupler.1.75 shafting & one rear bearing is all than is needed. More is not better. As for the dripless the PSI is the best choice. Just make sure you get a good water feed to the bearing. Do not remove a zinc for a water feed. High a plug high in the system to feed the bearing.
I repowered 31 jc w a 315 cummins 2:1 zf gear 23 by 24 inch 4 blade wheel drip less water out of wet exhaust 16-17 knot cruise 20.5 at2800 rpm that yanmar should run great in there good luck!
Correct gear for you & nice size wheel. The 315 Cummins turns much slower that the 315 Yanmar so even with the small est wheel you will be turning it faster so your speed should be the same. Keep in mind that the Cummins is rated at 2800 & the Yanmar 3800 RPMs. 1000 RPMs is a big difference. YOU vessel only has a shaft speed of 1400 RPMs which explains the larger wheel. The Yanmar with the 2.5 has a shaft speed of 1520 RPMs. That 120 additional RPMs explains the smaller wheel by about 3" of pitch. Which puts my EST of a 23 X 19 pretty close.I repowered 31 jc w a 315 cummins 2:1 zf gear 23 by 24 inch 4 blade wheel drip less water out of wet exhaust 16-17 knot cruise 20.5 at2800 rpm that yanmar should run great in there good luck!
the yanmar will fit nicely in the compartment, I just started stripping the motor for removal on Saturday and doing the usual garbage can full of wires and junk from a repower on sunday