2006 70hp yamaha trim tab

[99yam40]

makes you wonder what the other part # looks like.

Your old one looks like it has some life left in it, but it would be best to notch the new one while you can compare it to your old before it breaks. Just an opinion

[Jason2tpa]

Ive ordered numerous parts from boats.net, some of which had a superseded part #. This becomes more common the older the engine gets. But from my understanding, when a part # has been superseded its done so by the yam oem manufacturer. Boats.net as well as other yam oem distributors simply follow the oem manufacturer guideline for that specific part that has been superseded. So if you were to order using the original part # that has since been superseded by a new part #, they send you the superseded part.

Sure, human error in the distribution warehouse does occur. But if boats.net sent you the correct superseded part I find it highly unlikely it's the wrong part. Something else is going here.

I see you confirmed the correct prop is being used on your engine, but how about the correct hub kit, spacer, and washer. If any of these prop essentials are installed but are the wrong size this would offset the proper position of the prop when mounted. I'd double check these. Perhaps the previous owner installed the wrong hub kit, then had to knotch the anode because it's inexpensive compared to a hub kit.

[Jason2tpa]

Also, what is the more likely situation here:

*The part you received IS correct for your engine and you're supposed to knotch it yourself?

OR

*The part you received IS correct for your engine and some other factor has caused the prop to mount to far aft?


Highly unlikely the oem manufacturer requires the operator to jimi-rig a new part, a part indicated for your engine model. Just my 2 cents.

[Jason2tpa]

70TLR motor. Prop diameter is about 13-1/2".
Prop: Michigan Wheel, Avenger 103163 - 13 3/8 x 15

According to michigan wheel website, the avenger prop is obsolete. The prop model number you listed (103163) has been replaced by prop model 993143, the apollo series. Ironically I have this prop.

I'm thinking this issue is hub related, the previous owner having a obsolete prop could have installed the wrong hub kit for the engine. Like I mentioned in previous post I'd check the part # of the hub kit. Then contact michigan wheel directly, make sure the hub kit is intended for the 103163 prop.

[robert graham]

Your old trim tab looks fine to me...it's supposed to show signs of corrosion so it's doing it's job....why replace it???

[TownsendsFJR1300]

+1 ^^^.

Should you end up modifying that tab, I would suggest all your cuts are rounded and filed smooth. Less chance of cracking fatigue and that big flat part
where it was cut is no where near hydrodynamic (like pulling a brick behind you).

And adjusting (the original hacked one) it to help with steering would be about useless with a large frontal area vs a sharp edge...

I lost about MPH on the top end just adding a Skeggard (which fits very tight to the skeg)

[Jason2tpa]

That skeggard is soo sweet. I was in west marine the other day and saw one on the shelf. The price shocked me, but what the hell right. Only live once. Might as well have your skegg looking good and protected at the same time.

[TownsendsFJR1300]

That skeggard is soo sweet. I was in west marine the other day and saw one on the shelf. The price shocked me, but what the hell right. Only live once. Might as well have your skegg looking good and protected at the same time.

Buy it direct from Skeggard, it's a bunch cheaper and I had mine custom made.

The drain hole STOCK is in the front. I wanted it at the rear. He had to put the drain hole on the side, just about at the very back tip. This is so it'll drain as the pic shows and I didn't want dirt / crap crammed into a front drain hole.

Back to the thread...

[99yam40]

I just wear my skegs down in the mud and sand around here so there is less drag

[greglwake]

Talked to the marina that put the on the prop. He said they had to grind the tab because this prop has a bigger rake than the original prop. The 70TLR Yamaha has a shorter base than the bigger Yamaha motors.

Thanks everyone for your help! Happy New Year!

[Jason2tpa]

The prop must have a whole lotta curved rake to interfere with the anode. Standard rake for props is 15°. Yours must be near or at 30°, which is more common for high performance props. Boats with these high angle rake props regularly experience cavitation and ventilation. The high rake angle blades are able to grab more water in this situation verses standard rake props.

Just curious...why are you using a prop with such a high angle of rake?

[greglwake]

Jason,
Just bought this boat used last year and didn't know much about the different props. The guy who had the boat before me said he upgraded the prop a few years ago. The guy I talked to at the marina said it is a great prop.
This is all a learning experience for me.
Greg

[Jason2tpa]

Jason,
Just bought this boat used last year and didn't know much about the different props. The guy who had the boat before me said he upgraded the prop a few years ago. The guy I talked to at the marina said it is a great prop.
This is all a learning experience for me.
Greg

Gotcha. Depending on the weight of your boat, too much rake will cause excessive bow lift as it relates to throttle and trim position. If you find your bow will porpoise at low speeds and/or with small incriminats of trimming up from engine full down, then you'll now know the culprit.

[greglwake]

Thanks Jason for your input, I will see how the boat handles regarding trimming and changing of speeds. Won't be putting boat in water until spring.