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Hey Everyone,
I've got an 11' BobCat Tunnel hull w/40HP Tohatsu 2 stroke. The boat came with a manual jack plate & at some point someone put a hookey-dookey power trim unit on it I guess. The transom had about a 6" x 4" hole in it, I assume for the power trim cylinder. The hole had a rubber boot on it to minimize swamping the hull, but honestly, it looked totally stupid & unsafe so I eliminated it. I've owned other larger recreational outboards with power trim & figured I could get by without it on this one until I got used to it.
Upon my initial runs in the boat the darn thing wouldn't get on plane. So I lowered the jack plate & tucked the motor in all the way. Got it to plane, but there's too much hull in the water. So I started moving the motor away & was able to get more hull out of the water, but had a hard time planing. The other problem I'm having is that the RPM & speed is not there. I'm only putting out about 3600 RPM under load (I'm getting easily over 5000 on the trailer) & 35 MPH tops. So I've tried propping down, from a 13 cleaver 3 blade to an 11 3 blade SS, almost no improvement. As the boat transitions from cavitating to on plane, for about 2 seconds the RPM shoots up, you can feel a thrust in MPH, then as the hull planes, the prop must be setting back into denser water, & drags the RPM back down. So I think that the power trim needs to be there to get the prop into looser water (if there's such a thing) that allows the prop to slip a bit & increase RPM.
I believe this motor should be capable of about 5500-6000 RPM & about 50-55 MPH. If you have any ideas, advise, or anything that can make me feel slightly scared as I drive this thing, I'd be happy. Right now it's as boring as an old Sea Doo.
So if you think I'm on the right track with the power trim, what brand, year, make, model have you guys used on this Tohatsu application. I was thinking of buying one of those aftermarket power trim units, but was concerned that the increase set back these units create would possibly add to my problems, keeping in mind that my jack plate already adds about 4" of set back. What do you think?
I've got an 11' BobCat Tunnel hull w/40HP Tohatsu 2 stroke. The boat came with a manual jack plate & at some point someone put a hookey-dookey power trim unit on it I guess. The transom had about a 6" x 4" hole in it, I assume for the power trim cylinder. The hole had a rubber boot on it to minimize swamping the hull, but honestly, it looked totally stupid & unsafe so I eliminated it. I've owned other larger recreational outboards with power trim & figured I could get by without it on this one until I got used to it.
Upon my initial runs in the boat the darn thing wouldn't get on plane. So I lowered the jack plate & tucked the motor in all the way. Got it to plane, but there's too much hull in the water. So I started moving the motor away & was able to get more hull out of the water, but had a hard time planing. The other problem I'm having is that the RPM & speed is not there. I'm only putting out about 3600 RPM under load (I'm getting easily over 5000 on the trailer) & 35 MPH tops. So I've tried propping down, from a 13 cleaver 3 blade to an 11 3 blade SS, almost no improvement. As the boat transitions from cavitating to on plane, for about 2 seconds the RPM shoots up, you can feel a thrust in MPH, then as the hull planes, the prop must be setting back into denser water, & drags the RPM back down. So I think that the power trim needs to be there to get the prop into looser water (if there's such a thing) that allows the prop to slip a bit & increase RPM.
I believe this motor should be capable of about 5500-6000 RPM & about 50-55 MPH. If you have any ideas, advise, or anything that can make me feel slightly scared as I drive this thing, I'd be happy. Right now it's as boring as an old Sea Doo.
So if you think I'm on the right track with the power trim, what brand, year, make, model have you guys used on this Tohatsu application. I was thinking of buying one of those aftermarket power trim units, but was concerned that the increase set back these units create would possibly add to my problems, keeping in mind that my jack plate already adds about 4" of set back. What do you think?
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