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dcso408

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"i have 1988 sunbird cudy with

"i have 1988 sunbird cudy with a 1989 110johnson the boat is heavy with the 105lb kicker motor hanging of the back and it doesnt want to plane, it has a 13X19 prop should it be different with the extra load?
ted"
 
"Ted, can run a prop calculati

"Ted, can run a prop calculation for you but need some info - length/model of the boat would really help.

And was the outboard a "refit" - most sunbird cuddy's have I/O's up in the 200-220 hp class...."
 
"Ted, ran some numbers for you

"Ted, ran some numbers for you and while the 19 pitch is a little much, you are not severely over-propped.

My calculator kicked out a 15 pitch if you tend to run "heavy" (near max capacity) and a 17 pitch otherwise.

If you have a tach onboard, you should be looking for about 5200-5300 rpms running wide open. If you are getting somewhat less than that, for every 1" less pitch you run compared to your current 19", you would see an increase of about 200 rpms.

So I would tend to suspect that the boat not getting on plane is not entirely due to the prop. Since you have added extra weight to the stern (kicker) you may simply have to adjust your trim from what you were used to, to get the bow to sit back down properly and get the lift at the stern.

Alternately, a hydrofoil or trim tabs may do the trick if adequate compensation can not be achieved with trim alone..."
 
Ted I have a 19 foot Olympic f

Ted I have a 19 foot Olympic fiberglass V hull with a hard top and it had a 1987 Johnson 110 on it. I had to run the 14 x 17 pitch prop on it. Your boat sounds a little heavier than mine so Graham is probably right on with the 15 pitch prop.
 
"thanks,
i ordered a hydrafoi

"thanks,
i ordered a hydrafoil and i'll going to get a 15 pitch prop, i just think its just to heavy now with all the fishing gear for the 19"
 
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