ProV 150 lower unit rudder ?? speedo port issue too

[MikeD]

on the lower unit there is a small rudder flap that looks to be adjustable and probably has something to do with the steering. not sure what its for or how to adjust it (or even what its called). right now its set all the way to the drivers side, how do I realign it and what sort of effect should it have? I've tried moving it by hand but it won't budge, didn't see a jam nut anywhere for it so I'm stumped.

And the tiny little port in the lower unit for the speedo, its blocked up and I'm only able to get a small piece of wire into the hole about 1/4" or so, how far back does the port go before it turns upward? thinking that working a small drill bit by hand in the hole would help clean it up, but don't want to cause damage...

any online parts explosion available? online microfiche?

any help greatly appreciated

[Ken]

Mike,
You can go to the online parts catalog (above) to see a diagram of your outboard.
The "rudder" is called a trim tab for the outboard. It serves two purposes. One, it counters the torque steering of the prop, and, two, it is also a sacrficial anode.
The trim tab is adjustable - it is held in place by a bolt that is accessable right under a plastic cap located just above the cavitation plate and at the rear of the lower unit (see diagram). You will have to use a metric socket and extension to get to it. Loosen just enough so that you can move the trim tab by hand. Do not over-tighten. For a right handed prop, the trim tab needs to be adjusted to the right -i.e. the trailing fin of the trim tab needs to be moved to the starboard side. Should be adjusted far enough to the right so that when you let go of the steering wheel it won't immediately turn to the starboard. There are four or five alignment "notches" just above the trim tab - I have mine set on "two".
Since the trim tab is made of zinc, it also serves as a sacrificial anode to help save the metal of the outboard from electrolysis. Check it from time to time - should show signs of pitting to indicate that it is doing it's job. Replace when this pitting gets bad enough.
The speedo pickup hole can be cleaned out with a small diameter drill bit - start with the smallest you have and slowly work it into the hole - twist it by hand so that debris will come out. You should be able to work it all the way back - about two inches. Then go up to the next size drill bit and do the same. Do not use a drill bit that is the least bit bigger than the hole.
Good luck [img]smile.gif[/img] ,
Ken K