Strange behavior from my YPVS servo

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Matty
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Strange behavior from my YPVS servo

#1 Post by Matty » Sun May 13, 2018 3:25 am

I'm getting a strange rapid oscillation in the YPVS servo at the tail end of it's cycle when the ignition is turned on, If I twist the pulley home it ceases.
Does anyone know what is causing this?

Image20180512_125150 by Matthew Leahy, on Flickr
I'm not a complete idiot...some parts are missing.

begbie
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Re: Strange behavior from my YPVS servo

#2 Post by begbie » Sun May 13, 2018 8:40 am

Sounds like your pv cables do not have enough slack.

Matty
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Re: Strange behavior from my YPVS servo

#3 Post by Matty » Mon May 14, 2018 4:50 am

Thanks Begbie, I'll double check them.
I'm not a complete idiot...some parts are missing.

MK
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Re: Strange behavior from my YPVS servo

#4 Post by MK » Mon May 14, 2018 7:14 am

Something got stuck and the jerking you see is the strategy to overcome it.
Check if the bowden cables pull out easily and if the valves rotate easily in their cylinder bores.
The latter one can be cured with using pliers to move them until it gets easier.
Bye
Martin

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phildu31
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Re: Strange behavior from my YPVS servo

#5 Post by phildu31 » Wed May 16, 2018 7:16 am

Does it occur with cables removed ?

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2smoke
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Re: Strange behavior from my YPVS servo

#6 Post by 2smoke » Thu May 17, 2018 12:04 am

Are the YPVS cables routed correctly between the rear pipes?
Colin

Matty
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Re: Strange behavior from my YPVS servo

#7 Post by Matty » Thu May 17, 2018 4:52 am

Thanks for the input folks, I'll check all this on the weekend.
I was initially thinking it might be a problem with the potentiometer in the servo or a problem with the controller but it makes more sense that it's a mechanical issue.
I'm not a complete idiot...some parts are missing.

Matty
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Re: Strange behavior from my YPVS servo

#8 Post by Matty » Sat May 26, 2018 4:29 am

So, disconnected the cables at the servo, servo operates as it should, disconnected the cables at the bell crank, the cables are free and operate smoothly, rotated the power valves manually about a dozen times, sprayed some lube on the linkages re-assembled and re-adjusted the cables and now eveything works just fine.
Thanks for all the suggestions folks.
I'm not a complete idiot...some parts are missing.

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