I/O (Sterndrive) Conversion to Outboards

tpenfield

tpenfield

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I got the 5 gallon pail of VE resin, but the delivery person must be holding my 1708 cloth hostage or something. Awaiting a ransom letter. . .

Meanwhile . . . I have taken a look at the transom. Flatness, height, bolt positions, etc.
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Honda-BF350-Flatness-1.png
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Flatness: I am thinking that I could use the cut-out pieces of Coosa from the transom along with some fiberglass putty to make/form a flat area (red dotted line)

Transom/Engine Height: By my best measure . . . the top of transom is 30.5" above the planing surface at the mounting point of the outboards. The spec. of the shaft length is 30.1" . . . making the ventilation plate a wee bit (0.4") above the water stream. There is a 'rule of thumb' when extending the outboard on a bracket . . . 1" of engine height for every foot of bracket extension. I asked about the science behind this 'rule of thumb' on another forum and a bar-room brawl ensued. :ROFLMAO:

My splashwell bases block the lower position on the top series of holes. That should not be a problem, as the upper holes are what matters. FYI - The BF350 gets 2 top bolts on each side (i.e. 4 bolts) and then 2 lower bolts in the slotted area.

In my on-water testing after 'splash day', if it looks like I need to raise the engine, I can probably get 0.5-1.0" inch without any problem.
 
alldodge

alldodge

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tpenfield said:
I got the 5 gallon pail of VE resin, but the delivery person must be holding my 1708 cloth hostage or something. Awaiting a ransom letter. . .

Meanwhile . . . I have taken a look at the transom. Flatness, height, bolt positions, etc.
.
View attachment 415305
.
Flatness: I am thinking that I could use the cut-out pieces of Coosa from the transom along with some fiberglass putty to make/form a flat area (red dotted line)

Transom/Engine Height: By my best measure . . . the top of transom is 30.5" above the planing surface at the mounting point of the outboards. The spec. of the shaft length is 30.1" . . . making the ventilation plate a wee bit (0.4") above the water stream. There is a 'rule of thumb' when extending the outboard on a bracket . . . 1" of engine height for every foot of bracket extension. I asked about the science behind this 'rule of thumb' on another forum and a bar-room brawl ensued. :ROFLMAO:

My splashwell bases block the lower position on the top series of holes. That should not be a problem, as the upper holes are what matters. FYI - The BF350 gets 2 top bolts on each side (i.e. 4 bolts) and then 2 lower bolts in the slotted area.

In my on-water testing after 'splash day', if it looks like I need to raise the engine, I can probably get 0.5-1.0" inch without any problem.
Click to expand...
Maybe discuss with NA but I'm thinking the drive height might benefit higher

Why

Using Crap----erall insight, they have the motor height higher than bottom of hull. The forward power is good, reverse not so much. The motors are set back further so water will come up prior to making contact
 
P

Pmt133

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I watched a guy from bluewater talking about mounting height, he was saying every 10 inches back from the end of the running surface they move them up an inch or so as a "rule of thumb" Since the running surface is being extended here, they may not end up being "up" all that much.

I'd imagine you want the AV plate around the surface. My drive is completely buried at wot but I can't easily fix that... tis a wee bit more difficult with an I/O.
 
redneck joe

redneck joe

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Ah, forgot about that. I've only mounted one outboard.


And side note, my seemingly stupid questions are all asked thru ignorance (or as in the above forgetfullness) but as with all my life I've always been the one to ask rather than pretend im cool and all that sh.t so others don't feel stupid for asking questions.

This thread is highly technical and I will retain about 5% of what I read here but others may gain more than me. My first post on a boat forum in 2005 or so was about a bayliner boat on tht. I was roasted without mercy. After my initial embarrassment I decided to be the one to ask stupid questions so others did not have to feel what I felt 20 years ago.

So, answer my stupid questions.
 
Last edited:
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Pmt133

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redneck joe said:
Ah, forgot about that. I've only mounted one outboard.


And side note, my seemingly stupid questions are all asked thru ignorance (or as in the above forgetfullness) but as with all my life I've always been the one to ask rather than pretend im cool and all that sh.t so others don't feel stupid for asking questions.

This thread is highly technical and I will retain about 5% of what I read here but others may gain more than me. My first post on a boat forum in 2005 or so was about a bayliner boat on tht. I was roasted without mercy. After my initial embarrassment I decided to be the one to ask stupid questions so others did not have to feel what I felt 20 years ago.

So, answer my stupid questions.
Click to expand...
There's no stupid questions sir. The dumbest are simply the ones never asked.

Went through this at work a few weeks ago. I'm not an electrician by any means but ours rewired a VFD cabinet and we were not getting any control of the VFD through the system. He starts ripping apart his wiring thinking he wired it wrong and I just go "what if it isn't wired wrong but rather the loop for the data isn't complete and its only doing what it can do not what its told to do." Sounded dumb at the time but came to find out the next afternoon that there were a set of latching relays for the soft start (not documented of course) that also completed the signal loop and were preventing it from relaying the run signal. Simple repin of 1 wire was all it took. And then I felt pretty good I was on the right track that it was just doing what it was told.
 
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