Flo-Torq hub kits for Yamaha

[Pescadora]

This is cross-posted from the Prop section because it is pertinent to Yamaha engines. Moderaters, please forgive it this breaks a rule.

I've been exploring the use of the FT IV hub for my 2005 F150 yam to solve a vibration problem at idle. I've found a source for the parts but they are not returnable, which means you have to do your homework before plunking down the cash.

In the pictures they sent me, it looks like the inner splined collar which rides on the output shaft now extends fully through the delrin insert. The thrust washer appears to have its own collar which rides inside the forward end of the splined collar. In this rig, the forward half of the Delrin spacer engages the square cavity in the prop, while the back half does not. The back half engages only the output shaft. The two halves are mated with titanium rods molded into both sections.

Under power, the titanium bars flex, in effect acting like torsion springs which absorb vibration. The design won awards in the plastics industry.

But the questions for me remain:

1. Do the Yam F150 and the Mercury Verado have identical splined output shafts on the their respective gearcases.

2. Are the thrust washers for both engines are the same.

My engine came from the dealer with a FT II hub kit and a Merc prop but I don't know if that kit was Tam specific. IF the answers to 1 & 2 are both yes, then the FT VI hub kit is a bolt-on.

 

[Ray Neudecker]

Re: Flo-Torq hub kits for Yamaha

No to both questions. The Mercury kits for the small shaft Mercury works fine on the Yamaha. the Verado shaft is larger.

 

[rodbolt]

Re: Flo-Torq hub kits for Yamaha

actually there are some other differences as well.
would it be to easy to order the correct hub kit for your yamaha and be done with it?

 

[Pescadora]

Re: Flo-Torq hub kits for Yamaha

It's my understanding that FT IV kits will be made only for Mercury outboards.

If so, I'm out of luck.

 

[rodbolt]

Re: Flo-Torq hub kits for Yamaha

I have them at the shop for J/E, Yamaha,suzuki and honda.
most likly there are a few more.
michigan wheel makes the kits as well as brunswick.
follow the torque spec carefully, if its loose the hub tends to split.
the larger the motor the worse the splitting.
why would you suspect the prop only at low speeds ?

 

[Pescadora]

Re: Flo-Torq hub kits for Yamaha

You have FT IV hub kits for Yamaha F150? Superb! This is the first indication I've had of existance of said kit since learning about the design, even after a LOT of Internet research.

Stainless props exhibit a randomly occurring periodic vibration on my motor. During this period, the motor sounds like one or more cylinders is cutting out. Careful analysis by my dealer certifies the engine as okay and this happens only with heavier stainless propellors and only at idle.

The head mechanic hypothesizes that a big 4 cyl like the F150, because it has less power "pulses" than its V6 cousins, develops the rattle I've described due to normal play in the gearcase dogs. The FT II hub may or may not be adding to the problem.

A FT VI, with its spring-loaded dampening, might eliminate a mildly annoying, sometimes happening, problem altogether.

Interesting this never happens when trolling, albeit I troll at just above idle. It also never happens when first putting in gear. It comes and goes when the boat is moving 3-4kt with the engine idling. Minimum load on the propeller.

In the final analysis, I can live with it as is. But if the FT IV works, all the better.