VeroWing
Petty Officer 2nd Class
- Joined
- May 16, 2009
- Messages
- 150
I recently purchased a pair of 2002 Tohatsu 115/140hp 25" outboards to use on my 22' Grady White Seafarer. I removed a single 200hp Johnson 25" outboard. I am presently completely rebuilding transom area inside the outer fiberglass hull before installing engines.
I have search all twin installation info both here and elsewhere and it would appear that 26" center to center is the right number to shoot for when mounting engines. If I do these numbers and mount engines in those locations, then the cavitation plates on engines will be three (3") below bottom of hull. Seems to me that this would create a lot of drag and be inefficient I'm not sure but engines look as if a 5" section can be removed and maybe a shorter shaft and shiftrod can be obtained to make engines 20" shafts, which will put cavitation plates 2" above bottom of hull when installed. This probably will be a problem too.
Another choice I may have, although a somewhat more complicated one, would be to raise the notched area of the transom 3" which will make the cavitation plates flush with bottom of hull. I would have to fiberglass and gelcoat a 3"x54" section above the existing notch area, but as stated above, the transom is being rebuilt, and is presently stripped down to only the exterior fiberglass shell.
I'm sorry for being so long-winded, but I need to give all the info so I can get some good advice and opinions from others here. So what do you think, mount motors as is, with cavitation plate 3" below hull? Change shafts, shiftrod, and remove 5" section making 20" shafts, and making cavitation plates 2" higher than hull bottom when installed? Raise notched area 3" on transom that is currently apart?
All opinions and advice is greatly appreciated. Thanks, Mike.
I have search all twin installation info both here and elsewhere and it would appear that 26" center to center is the right number to shoot for when mounting engines. If I do these numbers and mount engines in those locations, then the cavitation plates on engines will be three (3") below bottom of hull. Seems to me that this would create a lot of drag and be inefficient I'm not sure but engines look as if a 5" section can be removed and maybe a shorter shaft and shiftrod can be obtained to make engines 20" shafts, which will put cavitation plates 2" above bottom of hull when installed. This probably will be a problem too.
Another choice I may have, although a somewhat more complicated one, would be to raise the notched area of the transom 3" which will make the cavitation plates flush with bottom of hull. I would have to fiberglass and gelcoat a 3"x54" section above the existing notch area, but as stated above, the transom is being rebuilt, and is presently stripped down to only the exterior fiberglass shell.
I'm sorry for being so long-winded, but I need to give all the info so I can get some good advice and opinions from others here. So what do you think, mount motors as is, with cavitation plate 3" below hull? Change shafts, shiftrod, and remove 5" section making 20" shafts, and making cavitation plates 2" higher than hull bottom when installed? Raise notched area 3" on transom that is currently apart?
All opinions and advice is greatly appreciated. Thanks, Mike.
