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Is the general application that you put a 25" shaft on a 25" transom? I'm getting a Sea Pro SV2100 that has a 25" transom with a pocket tunnel. The dealer is pushing a Yam VMAX 200 EFI OX66 because it is a 2003 inventory item, and cheaper to me too, but it has a 20" shaft.
The boat I drive now is 25" to 25" with a tunnel. Need a little help here.
Thanks. I agree that it should be a 25 over 25. I'm waiting for the dealer to explain to me why he didn't say it was a 20 when we ordered the boat. I understand that it was really my fault for not checking on the shaft length in the first place and assuming it was 25. But before I clamped down on the dealer, I wanted to find out if anyone heard of a 20 on a 25 transom. I'm new to this forum but really enjoying reading the comments. I have learned more about boats and motors by reading the 4 forums,Texas Fishing Forum, Louisiana (Rod and Reel), Florida Sportsman and THT, that I have subscribed to in the last 3 months, than I learned in the previous 8 years that I've owned a bay boat. Most of you are from Florida and my fishing is done around Port O'Connor, Texas, about 35 miles south of my home in Victoria, Texas.
Thanks. I agree that it should be a 25 over 25. I'm waiting for the dealer to explain to me why he didn't say it was a 20 when we ordered the boat. I understand that it was really my fault for not checking on the shaft length in the first place and assuming it was 25.
I disagree. If the dealer ordered you a boat that calls for a 25" OB and specified a 20" OB for it he is either negligent or fraudulent.
Nothing good can come from having a 20" shaft motor on a boat that calls for a 25" shaft. Don't see how it could even begin to plane.
I'm with Canazes9 - I bet you have a jackplate and that is why the dealer put the 20" on there. I've seen that happen before. I don't know much about the pros and cons of doing that but when I bought my 2300V a couple years ago, they had just gotten a 2300 tunnel with a 20" Merc on it with a Jackplate.
It is going to have a Bob's jack plate, 6". The concensus of the opinions I am getting from you gentle people is that it should be 25 on 25, tunnel or not. Right?
A local, fairly knowledgeable, dealer told me that ....for every two inches of set-back ( jackplate etc.) you should RAISE the motor one inch. This statement was on a non-tunnel hull, however. If you have a 6 inch set-back, it may be that the shorter by five inch motor shaft is really only short by two inches. That may, or may not, be made up by the mounting of both the jack plate and the motor itself, on the jack plate. Seems like a long talk with your dealer and his installation man is called for. I've had the other problem.. a 20 inch shaft on a 15 inch transom. When I added a CMC-PT35 tilt & trim, it setback the motor, and my dealer raised the motor to it topmost positon and it worked out just fine. Hope it works out, one way or the other. RichG
With all due respect to your dealer that's not always true - can be, not always. My earlier post was only in reference as to whether or not that combination could be made to work - it can. Do I think it's the way to go when buying new - absolutely not - get the benefits of the 25" shaft, if the motor is setup right on the Bob's plate it just gives you more options. The dealer is wrong and it is his responsibility - I would not accept a new hull like this.
Friends, here is the latest. I really wish I knew more about this subject so I could argue with the dealer about it with more confidence.
Get this. After telling the dealer yesterday that I was not happy with the 20" shaft, for all of the reasons discussed here (flexibility, mfg. specs, etc.), the dealer says that the motor will be too deep if it is a 25" motor because this is a V hull!!! That really got me. The web page for the SV2100, as we know, calls for a 25"o\\b. I guess if I had ordered an HPDI, which only comes in 25" and 30" at 150 h.p.and higher, that the shaft would have been too long.
Then he said because of the tunnel, the transom is in essence a 20" transom. I told him that I was not concerned about the distance from the top of the transom to the top of the tunnel cut.
I'm not looking for an argument with the dealer. Am I misunderstanding something on this? I told him I would be there at 8:15 in the morning, about a 2 hour drive from my home, but I do want to get this right. I have, in essence, sent this same message to the manufacturers rep and asked him to contact me about it, too.
Any ideas or suggestions? It's o.k. to call me a Dumb A__ if I deserve it, just tell me where I'm wrong.
I think you can cut to the chase by calling Sea Pro and speak with them. They will be able to concrete this question.
I like the majority in this forum feel a 25" is without a question the motor to go on that transom. Call them today. It will most likely cost less than five bucks to call them and wow the best five bucks you could ever spend.
You will be better prepared to discuss this with this dealer. If Sea Pro says "NO" to the 20" shaft they will most likely be very interested in who has misrepresented their documented engineering design. If they say sure no problem then at least you will have the hull designers input. If anyone factually knows what that hull can take as far as shaft size, they will know
Once you get it on the water and find out the performance is poor it will probably be way too late. Therefore I personally feel to not call Sea Pro would be misrepresenting this questionable situation and on a very costly endeavor. It's your money. To the best of your ability, do it right the first time, you won't regret it!
Transom size and shaft size 
