'77 Johnson 115hp.

How do I set the trim tab vane on the lower unit?
It's easy to physically loosen, set, and tighten. However, what I'm asking
is where to set it, how to know if it's the right setting, etc. I seem to
remember it's some kind of trial and error thing, but I don't know what to
look for. Please give me a quick crash course in the care and feeding of
that thingee.

"RB" wrote in message
...
'77 Johnson 115hp.

How do I set the trim tab vane on the lower unit?
It's easy to physically loosen, set, and tighten. However, what I'm asking
is where to set it, how to know if it's the right setting, etc. I seem to
remember it's some kind of trial and error thing, but I don't know what to
look for. Please give me a quick crash course in the care and feeding of
that thingee.



Just center the torque tab and run at cruising speed to see which way the
boat wants to track.

If it tracks to the port side adjust it in small increments counter
clockwise (looking from above) until the boat tracks straight (or clockwise
if it wants to track towards starboard). Make sure you adjust in small
increments, it usually doesn't take much.

On mine ( which was an outboard - but the same changes are necessary)...My
boat ran to the starboard (right) when idling along. I moved the trim tab so
that it pointed to the left (port) to correct the right-handed drift. I
thought of it as a sailboat's rudder. Opposites work.
--
RichG
http://groups.msn.com/CarolinaSkiffOwners
"RB" wrote in message
...
'77 Johnson 115hp.

How do I set the trim tab vane on the lower unit?
It's easy to physically loosen, set, and tighten. However, what I'm asking
is where to set it, how to know if it's the right setting, etc. I seem to
remember it's some kind of trial and error thing, but I don't know what to
look for. Please give me a quick crash course in the care and feeding of
that thingee.

Good answers. Thanks.

It's possible I need another coffee, but I think the two answers from Joe
and RichG are actually incorrect. I'll try not to screw this up, but here's
what I think I know.

1/ The tab isn't for low speed use, it's for planing speeds.
2/ You move it the "wrong" way to make it do the right thing. The reason
for this is that it steers the outdrive, not the whole boat. So, if your
boat, on plane, steers to port, you want it to steer more to starboard (to
go straight), so that means the outdrive has to turn to starboard, but that
means the front of the outdrive is now aiming more to port (because you push
the stern to port to turn the boat to starboard...), so to use to the little
trim tab "rudder" to steer the outdrive that way, and because that little
"rudder" steers the "stern" of the outdrive the same as a big rudder steers
the stern of a boat, the trim tab's trailing edge is turned to port to make
the outdrive aim more towards port (which we call turning the outdrive to
starboard).

There, that wasn't so hard. A few points:

Turning the outdrive to port would be clockwise, from above. That's the
opposite of what Joe said. (Awfully sorry, and I hope I'm getting this
right.)

If your boat turns to port, turning the trim tab to port initially looks
wrong. That's because, as said, it's to turn to the outdrive, not the whole
boat.

Turning the trim tab to port is actually making it aim to starboard, but the
nomenclature of rudder usage dictates that we use the side towards which we
swing the trailing edge. (Dontcha' just love this?)

====

Charles T. Low
- remove "UN"
www.boatdocking.com/BDPhoto.html - Photo Contest
www.boatdocking.com
www.ctlow.ca/Trojan26 - my boat

====

"RB" wrote in message
...
'77 Johnson 115hp.

How do I set the trim tab vane on the lower unit?
It's easy to physically loosen, set, and tighten. However, what I'm asking
is where to set it, how to know if it's the right setting, etc. I seem to
remember it's some kind of trial and error thing, but I don't know what to
look for. Please give me a quick crash course in the care and feeding of
that thingee.

"Charles T. Low" wrote in message
news
It's possible I need another coffee, but I think the two answers from Joe
and RichG are actually incorrect. I'll try not to screw this up, but
here's
what I think I know.

Nope, I think we're saying the same thing (you and I).
If the boat tracks to port, you turn the tab counter-clockwise (looking from
above) to compensate.
Turning counter-clockwise turns the tab towards port.

If I explained the "fix" incorrectly, then I apologize, ...........but
......Joe's clarification seems to agree exactly with my rudder analogy.

All I can say for sure...is that the "opposites" method fixed my running to
starboard problem!

If you are running to Starboard,..and want to go to Port..(actually back to
neutral), you "point" the fin to starboard..and vice versa...
--
RichG
http://groups.msn.com/CarolinaSkiffOwners
"

Ah... haaa! After re-reading my OWN explanation...I can see why I probably
confused some people.

It is my use of the word "opposite".

I think we are all saying the same thing, but using different words (with
mine perhaps the most unclear).... sorry.

I guess it comes from sailing with a tiller for so many years.
--
RichG
http://groups.msn.com/CarolinaSkiffOwners

I accept that I did indeed need another coffee before my reply yesterday.
And at one point I said "outdrive" when I meant "trim tab," for example.

So, everyone agree on this? Boat pulls to port. Want to have it self-steer
more to starboard (to go "straight"). Require swinging (trailing edge of)
outdrive to starboard. That requires turning trailing edge of trim tab to
port. That is _clockwise_ when viewed from above - I am going to be stubborn
about that. Would a schematic help?

Charles

====

Charles T. Low
- remove "UN"
www.boatdocking.com/BDPhoto.html - Photo Contest
www.boatdocking.com
www.ctlow.ca/Trojan26 - my boat

====

Nah..no schematic needed here.

Boat goes to Port...
You want it to go straight..
Point the tab to Port.
OK here.
--
RichG
http://groups.msn.com/CarolinaSkiffOwners
"Charles T. Low" wrote in message
...
I accept that I did indeed need another coffee before my reply yesterday.
And at one point I said "outdrive" when I meant "trim tab," for example.

So, everyone agree on this? Boat pulls to port. Want to have it self-steer
more to starboard (to go "straight"). Require swinging (trailing edge of)
outdrive to starboard. That requires turning trailing edge of trim tab to
port. That is _clockwise_ when viewed from above - I am going to be
stubborn
about that. Would a schematic help?

Charles

====

Charles T. Low
- remove "UN"
www.boatdocking.com/BDPhoto.html - Photo Contest
www.boatdocking.com
www.ctlow.ca/Trojan26 - my boat

====