yamaha f100 efi downgrade to f90

[jasoncallej]

Hi all I have a problem with the Malta marine authority I have boucht a yamaha F100 efi 2012 and they did not to register it on my 16ft rib as they told me that the boat builder specs are 60 hp now I decided to buy another rib 17.5ft but the builder specs for it are maxximum 90hp and they don't want to accept the 100 on it. Now I want to aske you if there is a way to down grade the f 100 to f 90 I know that they are the same but I need to do somthing to show them that the motor have been downgraded to 90. Thanks guys and sorry for my spelling mistakes.

[almetelo]

According manual parts diferent cylinder head assy, Camshaft1 and ECU besides a few minor as thermostat etc
A simple but expensive ECU change may work but how they know the motor is with 90HP? They will do a dyno test?

I understand your problem... In Portugal we are getting the same "problem" since a few years ago...

My OBE 470 Fisher is rated 25HP max and are around a few with 60 enduro and a lot with 40 hp and today thats completly impossible.

Good luck

[boscoe99]

Try and fool the authorities. Sort of. Kind of.

Make up your own restrictor plate to be added to the intake system. Somewhere ahead of the throttle body. Try and convince them that the restrictor plate is going to be reducing the maximum HP by 10 HP at least. Maybe more.

You can cite Yamaha as having done this on other models. Tell them about NASCAR (hope you have heard of them) who use restrictor plates on race cars to lower the maximum HP.

Another thought. Yamaha lists the maximum HP at 100 at 5500 RPM. Tell the authorities you will install a placard on the help that restricts the WOT RPM to 5300 to get the HP down.

Is there any way to register the boat without a motor being installed? By telling the authorities it will be used with oars maybe? If they register it sans a motor, then install the motor later.

Or, talk to the boat builder to see if they can issue you a one time approval to install and use a 100 HP motor on the boat on the basis that you will not run the motor at wide open throttle.

[Timbuktu]

Needs a new decal good luck

[jasoncallej]

This is my problem that here in malta there are boats registerd before the entry to the EU That they don't have any certifications so they can install any hp like 16ft with 115hp and 18ft with 225hp. My boat is all redy registerd with a 60 hp and when I installed the yamaha100 and went to do the change of engine they wanted a servior report and the busted reportet me that I was going to be overpowerd and now there is nothing to do as they have all ready have my history. But now I dicided to sell my rib and buy another new rib but its specs are 90hp maximum and the certification canot be udjusted to 100 because normaly the maxximum hp of a boat it will be 90 or 115 hp next week I will speak to yamaha dealer may be he will find me a solution as I realy want to keep this motor it is my first yamaha and I realy love it

[Timbuktu]

You may want to try to contact the Rib boat company and get them to write you a cert letter for your HIN, there is a chance that a knowledgeable engineer may write you a letter certifying a motor that is the same weight as the 90 for the rib. It's worth a shot.

[jasoncallej]

I have tride with the agent of the rib but he told me that
he can't do it now as told before the other new rib is certified
To 90hp and even this maker can't do this modifications
I will have to buy a rib that have certification for 115hp and I will
be coverd

[almetelo]

Try the manufacturer of the rib not your local dealer and explain your situation... tell you really love the rib but economically is easyer trade the rib and not the motor and that for now you can't go for the next model and you have to sell the rib... use some pretty words when talking about the rib lol
Other option is contact your local yamaha dealer and ask for a statement saying that you motor is underpowered (even if not and even if you have to pay for this)
Here in PRT some local dealers do that... Some in fact have a restrictor on the intake or something else but others not...
As in Malta I guess is not offered a F90 for sale but just F80 and F100 you have to add a air intake restrictor that is used on F80 (a few say just removing that restrictor youŽll have a F100 but isn't (here we go again) and a F80 ECU. Try to convince you local yamaha dealer do the statement that with the that air restrictor you are with 80HP and not 100HP. Even If you have to buy that restrictor and show the autorities the invoice of purchase and open the intake to show them the restrictor on the intake (of course after survey you'll remove it...) with good will may be not hard to solve (my 2 cent)

I can post the manual parts with diferences if this may help.

Because of that and other things related we have:

Yamaha
F40Fisher=F60
F50Fisher=F80
F60Fisher=F100 and F115
F100Fisher=F150
and latest I found on a local community of fishermans was a F30Fisher=F70
At the moment Yamaha just sell them for professional fishermens.

Honda have
BF30PRO=BF50
BF50PRO=BF75 or BF90

Suzuki also to the same lol

I know in Spain they use the same system.

My motor is F50Fisher=F80 (that then I upgraded for F100) because my Sessa Key Largo 16 is limited to 65HP so I had to go on this way because I wanted to keep the boat (yes, at the moment with 100HP in my case I may be a little over acceptable but isn't your case)

Yes is a fraud and they know but before we had so much restrictions we didnŽt had this and the goverment is losing money in taxes! and Yes, we need rules but in my point of view some are really stupid... as the lowest marine licence limits the power of the motor to 40HP while with a drive licence we can drive any car like a Porche or a Ferrari with no power limits and that is not a problem!!!

[jasoncallej]

Yes that is as you said but this is a way of money making you buy a boat that can take a 60hp that can load 900kg including motor but when it come to a little rough sea you will not be able to go on plane so yo will have to upgrade the motor and boat and that is how it goes on and on that is why they don't want me to use a big outboard on my rib so if you need more power you need a bigger rib that is the responce I got. And the maker does not accepet emails from me and the dealer it is better for him that I buy another one but I will have a try againe as you said almetelo

[jasoncallej]

Hi all I have tride to ask the company to give me permition but they refused now I wish that you tel me what is the meaning of the serial no of my outboard as I got confused under yamaha there is 6D9 and the model F100DET I know f is for four stroke

[boscoe99]

Hi all I have tride to ask the company to give me permition but they refused now I wish that you tel me what is the meaning of the serial no of my outboard as I got confused under yamaha there is 6D9 and the model F100DET I know f is for four stroke

The model is F100DET. And yes, the F in a Yamaha stands for four stroke.

Then there is the primary ID. It will read something like 6D9L 1018900.

6D9 is the prefix code for a model F100DET. The next letter L will stand for the shaft length. L being a 20 inch shaft. The numbers denote the serial number.