21" transom and 25" shaft help

[madharchod]

i have a issue if some one call solve it ,the transom is 21" and some drongo ordered 25" extra long shaft two motors ,they are 115hp and while i was away on holidays they went ahead and put the motors on the boat and tested it,now the motors are used so the company wouldn't take it back and putting the engine right up ,we still need two more inches before we can get the boat to run at WOT which is 6500-6800 rpm at the moment we are getting max 5300rpm
need help here should i put jacking plate or what as the owner doesn't want any welding on his boat especially on the transom
pls help

[99yam40]

Jack plate is the answer, plus the set back may help also

[rodbolt17]

to my knowledge Yamaha doesn't make an engine that operates above 6000 RPM.

either rebuild the transom or jackplate it.

[BQUICK]

In the end it may be a better setup with the long motors. They will sit higher and get less splash.
I think he meant 5500-5800 rpm. Unless he has cut the rev limiter and wants screamers!

[madharchod]

my typing error RODBOLT mate the old age is getting to me as i have started too many holidays recently leaving the business to young fellas to run ,now they cant cope ,its supposed to be 5500 to 5800rpm instead of 6500 to6800rpm

[rodbolt17]

I got ya there .

the current crop of young techs leaves a bit to be desired in my opinion.

however at least they can still see.

I would move the engines up 5" and run them.

[madharchod]

no worries bud
i have to order two jacking plates from USA as this new customer has become a pain in the hind side complaining and winging all the time ,i have assured him i will look into his problem myself
thanks a lot bud