Elevator Cable tension

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Larry E
Posts: 23
Joined: Mon Sep 30, 2019 1:06 pm

Elevator Cable tension

Post by Larry E »

Good day all.
I am about to change the tension in the elevator cables (1953 170B) - they are a bit loose and the control Tee chain sprocket is about 1.5 inches aft of the firewall with the elevator full nose down (the rigging instructions say it should be 1/2 inch aft of the firewall). As near as I can figure, the lower cable at the rear bellcrank needs to be shortened to move the control tee closer to the firewall. So the upper cable would be lengthened first, then the lower shortened.

My question to those who've done it:

What is the easiest way: Crawling back through the fuselage; or adjusting the turnbuckles through the 3 inch inspection hole above the rear elevator bellcrank.

Any suggestions or hints (or indeed anything) would be appreciated. I'm tall, old and have bad shoulders and have never crawled past the rear of the baggage compartment in any Cessna. I'm thinking it might get uncomfortable...

Thanks
Larry
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ghostflyer
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Joined: Mon Apr 21, 2008 3:06 am

Re: Elevator Cable tension

Post by ghostflyer »

Elevator cables are a primary control and I would be using a a/p or a IA to do the adjustments/replacements . Elevator cable system has a number of components that have to work together and be rigged together. Personally I would get some one authorised to do the job as you could pull a muscle or hurt yourself. We are not all 21 these days and I am including myself in that bracket. Plus how old is your cables? If older than 10 years I would be putting in brand new ones. Especially the elevator cables. They might look good to you but to a trained eye and some one with experience with this area things could be ugly and not be apparent to you.
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c170b53
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Joined: Mon Apr 22, 2002 8:01 pm

Re: Elevator Cable tension

Post by c170b53 »

Access to the turn barrels is through the aft fuselage tail access hole. Not a nightmare job but the calisthenics involved will probably leave your tongue hanging out your mouth at the end. I prefer using a wire when adjusting cables but this job will be one handed so a clamp will work best. If you cable tension is low then tighten the cable in the direction you wish to move the column. After that its tightening equally if cable tension is still low. Once correct tension is achieved, the control must hit the travel stops. That’s the basics but having outlined the objective, I’ll just wonder why is the tension low? Is there something going on in the run?. For any control your want to double, the double check hence the norm is two licences, one guy does the work, the other does the independent check, both sign the work.
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
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Larry E
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Joined: Mon Sep 30, 2019 1:06 pm

Re: Elevator Cable tension

Post by Larry E »

Thanks for your input Jim.
This is the method my mechanic said he would use, but he also appreciates the wisdom and experience of the "Type Clubs". There will be double checks and double signatures.
Larry
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