Throttle creep

Throttle creep

Postby Nick » Sat Mar 03, 2012 10:56 pm

The throttle on my 260B started creeping out last year so that I would have to push it back into place. I have adjusted it several times in the last year. Now it does it continuously so that now I must constantly hold it in place to maintain the setting for cruise power. It can not be adjusted any more. Any suggestions? Anyone have access to a drawing that illustrates how the mechanism is desinged to keep it from doing this? Thanks. :?
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Re: Throttle creep

Postby N3322G » Sun Mar 04, 2012 12:54 am

Nick,

I just addressed this on my twin but don't know if you have the same style power quadrant - are they levers or push and turn?

Also the service manual is online under the tech tab if you want to read it.
Pat

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Re: Throttle creep

Postby 9089P » Sun Mar 04, 2012 2:38 am

Hi Nick,

Well you don't have the same arrangement as PJK if your 260B is stock. I assume you have the original throttle cable. If I recall correctly, from experience long ago, there is a washer type arrangement inside the adjusting nut you have been tightening which puts drag on the shaft and I believe one part of the assembly is made of leather(?). The leather eventually wears out and the drag assembly no longer works. It would seem this could be rebuilt.

An alternative, which I did, is to replace the throttle cable with a vernier type throttle which by design is always locked in the position you set and also allows for very fine adjustments. McFarlane supplied mine (in fact all 3 cables) and I think they make a superior product.

Good luck, Don
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Re: Throttle creep

Postby MULEFLY » Sun Mar 04, 2012 3:14 pm

Agree with Don... checking the locking mechanism... but I replaced the throttle cables on my 260B with cables from McFarlane
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Re: Throttle creep

Postby DAVEG24 » Sun Mar 04, 2012 5:32 pm

If you have the throttle quadrant type of control, I don't know how to fix. If you have a push /pull throttle, the fix is easy. Unscrew the friction lock, wrap a small piece of leather around the shaft, and re-install the locking control. It's simple, fast and effective. I'm not a big fan of vernier controls for the throttle, as they inhibit quick changes. Some like that feature, but I prefer to have more control. Just my opinion.

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Re: Throttle creep

Postby 9089P » Sun Mar 04, 2012 11:20 pm

Hi Dave,

I disagree with the thought that vernier throttles inhibit quick action. In panic mode the vernier hold is easily overridden as if it wasn't there. At least on mine it is and there wasn't any damage as a result.

Don

PS the quadrants did not come in on the singles until the C model.
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Re: Throttle creep

Postby DAVEG24 » Mon Mar 05, 2012 12:00 am

Hi Don,

You're right about the throttle quadrant and when it came into use. I should have checked that. I know that vernier's can be bypassed by pushing the button, but most people that I flown with that have verniers use the vernier function, which is slow in my opinion. Remember, this is just my opinion and has no bearing on those that use and like vernier controls. I also think it depends on whether you are running a carburetor or fuel injection. For a prop, there is no other way, also my opinion. At one time I considered changing over to a vernier throttle, but after flying with one decided I liked the original better. I guess it's a personal choice type of thing, with no clear, definitive answer.

How are things in California?

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Re: Throttle creep

Postby 9089P » Mon Mar 05, 2012 3:27 am

Hi Dave,

Absolutely it is personal preference. We had an ordinary March day here, 74F, light and variable, 40% humidity and cavu.:-). With that , wish we were flying to Alaska this year but building a home in Moab, UT and that is cutting into the fun travel time. Mostly going up and down the state for fun. Hope all is well with you all.

Don
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Re: Throttle creep

Postby Andrew Foster » Mon Mar 05, 2012 3:57 pm

Webco has the part you seek
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Re: Throttle creep

Postby Nick » Tue Mar 06, 2012 3:47 am

Thanks for all of the replies. Lots of good info. :)
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