New prop hitting trim tab

[Dave Blaber]

Good day, I have changed my props from Aluminum 13 1/2 X 15-K to Apollo s/steel 13 3/8 X 15 on my 60hp high thrust 2007 four strokes, now the prop touches the trim tab, very slightly, see pic, is there another trim tab I can fit to suit these high performance props, thanks Dave

[greasyshaft]

You got the thrust washer the right way?

[DennisG01]

That's already a 'set-back' trim anode. Can't really get anything that's going to be further back. As mentioned above, check to see that it's mounted correctly. If it is, one option is to grind a little of the trim anode away, but it's going to more likely to break off given where the grinding is. I'm not sure whether being that close together will cause some cavitation, though.

To be honest, though, the difference between an aluminum and an inexpensive SS prop in terms of performance is going to very negligible -- especially on a smaller engine. Part of the problem, sometimes, is that the SS weighs much more than aluminum and smaller engines don't always have enough torque to spin-up the prop fast enough to take advantage of the benefits that an SS would offer. Depending on what you want, there might be better ways to accomplish this.

[Dave Blaber]

Thanks Dennis, I noticed the aluminum prop came very close to the tab, I have ground away +- 3mm off the tab, prop turns ok now( see pic ) , there is still a lot of meat left on the tab and filed it to a point to give smooth water flow. I will give it a try on the weekend and let you know how it goes, thanks Dave.

[TownsendsFJR1300]

You never answered Greasyshafts question.

Do you have the "Thurst washer", that goes on the prop shaft, BEFORE the prop, in the correct orientation?

Installing in the wrong direction will kick the prop out farther..

[Dave Blaber]

Hi, yes the thrust washer is the correct way, it slots into the housing behind the seal and the beveled edge is up against the shaft, the only way I can see this working is grinding the zinc as I have done, testing on Saturday will let you know, thanks Dave

[DennisG01]

Dave, just a general suggestion for the future. Whenever you make some kind of cut like that and are worried about the piece's integrity, don't make a "square" cut - meaning, avoid an inside angle like you have. That will create a weak spot where a crack can form and lead to breaking. Instead, make it a "rounded" inside edge. It can be a relatively small radius, but round is better than square. Now, in this case, it's a cheap part so no big deal - just a suggestion for later.

[Dave Blaber]

Thanks Dennis for the advise, I have ordered new zinks, I cut those in a bit of a rush, and ground a little too much away, I will take more time grinding the new ones, cheers Dave

[99yam40]

I believe they make some without the skegs for better clearance,
With twins running in different directions the prop torque may cancel and not be needed.

But I do not know that for a fact