wilhelm combi redux

[utupua4]

Thanks Wilhelm.

If ,by the sleeve, you mean the exterior of the shaft that is visible
between the combi/engine and the stuffing box. Yes, this moves
forward and backward and reflects the engine revolutions.
Visually from the cockpit floor opening everything looks good. If
the the prop feathering mechanism cannot travel the full distance
necessary to move the mechanism from reverse through neutral
into forward perhaps inner control rod has slipped or gone out
of adjustment. As it is I can go in reverse as per normal at the
appropriate engine speeds. In neutral the prop is feathered
properly. Advancing the leaver to forward increases engine
revolutions but does not feather the prop into forward. If I must
adjust the combi control rod can it be done at the combi/engine
side.

PS
When you suggest a repair while in the water, you imply working
in the engine room. If you are suggest adjustmentsrepairs to the
prop hub in the water......well ....the water on Lake Champlain is
50 F. I'm not made of the stuff to spend any time in water at that
temperature. Living in Florida, that constitutes a nice COLD drink
enjoyed in the cockpit after a sail where the temperatures have
been in the 90's

Waiting for a warm day

Best regards
Antonio

 

[wxt8981]

Hi Antonio;

The sleeve does not drive the prop. The prop is driven by
what you call the inner inner control rod (which is the
shaft!)

I guess the only way to find out that the sleeve changes
the pitch of the prop is to move the lever and see the
prop moving from fethering to forward all the way. But that
does require somebody checking the prop- outside! And as
you say- no fun on Lake Champlain.

Wilhelm, V-257

 

[wxt8981]

Antonio

it's the "inner control rod"... not 'inner inner'
My mistake

Wilhelm, V-257

 

[wxt8981]

Antonio;

the more I think about your problem I think there is a good
chance the sleeve has unsrewed itself from the prop. Try to
turn the sleeve; if it moves around, but the prop stands
still, then it is unscrewed (remember: left threat). The
reasoning is because your prop was entangled in the rope,
that could have enough force to unsrew the sleeve at the
prop. The sleeve does not drive anything- it only controlls
the pitch.

Wilhelm, V-257

 

[chris20636]

Wilhelm/Antonio,

If the control tube has unscrewed inside the prop boss, then I can see how pushing the control tube aft, would push against the gear that would pitch the prop one direction. However, I would think that trying to go back to neutral or the opposite direction, i.e. moving the control rod forward again, nothing would happen, since the control rod would just move by itself. So I'm wondering how he would be getting back to neutral. I would think he would be stuck with just one pitch on the blades.

The basic idea is that the inner drive shaft provides a fixed length from blades to engine. You then slide the control tube forward/aft to change the pitch of the blades. Since he can change some pitch, then I'm thinking that,

1) The shaft moved which changed the fixed length portion of the system. However, if that happened then I would think the neutral position would change. Has it? In this case the throttle handle may not be pushing the control tube enough to get to the forward pitch position. With this scenario, the control tube forward/aft movement should coincide with the prop pitch movement. However, if you can make the control tube slide forward/aft, without the prop changing pitch, then something is loose.

2) Is it possible that the prop bolt has broken or been stripped out? The prop boss is prevented from moving forward on the shaft by a tapered fit. It is prevented from moving backwards off the shaft by the prop bolt. Might it be possible that the prop boss is sliding off the back of the shaft, if the prop bolt is damaged? Without being on my boat right now to play with the controls, I can't imagine if forward control would lead to pushing the prop boss backwards or not.

3) The shaft could be loose. If that was the case then I think you would be able to see the gap between the propeller boss and the stern bearing change as you tried to change pitch.

Just throwing out some ideas.

Chris
V2933 Renee

 

[wxt8981]

Hi Cris;

you're right in about all points. My thought of the prop
being disconnected from the sleeve would just do what you
wrote: the sleeve would move out, but when returning, the
pitch would remain.

However, the shaft could have loosened at the engine's end
(don't think at the prop, unless the bolt broke), and that
would make the distance from the motor to the prop
different, resulting in producing an incomplete pitch-move.

The same could be true if the sleeve moved inside the
controll box; that would be the easiest thing to fix.
Antonio just has to loosen the bolt holding the sleeve at
the controll box and check the 2 rings that hold the
sleeve.

Whatever it is, I feel with Antonio.. and wish him well. I
have taken apart these things so many times and as a
suggestion for Antonio: if he has to haul-out the boat,
make sure to get all these 0-rings necessary to keep the
water out!

Wilhelm, V-257

 

[wxt8981]

Hi Antonio;

I hope you don't get tired reading my comments. I gave it
another thought: I don't really think the shaft could be
loose at the engine's side. The key holding the shaft isn't
very long, and if the shaft is beyond the key, the engine
no longer would drive the prop.

You "may" have only a very minute problem: Check the
movement of the control (from the cock-pit to the
control-box.) There are notches outside and at the control
box indicating where neutral is. Be sure the control lever
lines up with the notch- it should be neutral at the prop.
If not, the control lever can be reset. You don't have to
go into the water- just run the engine and when you feel
the prop is in neutral, all notches should line up.
However, to check the pitch (either forward or reverse),
you may have to dive down.

Wilhelm, V-257