Matronics Email Lists :: View topic - Prop not cycling during run up

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Prop not cycling during run up

Matronics Email Lists Forum Index -> Yak-List

View previous topic :: View next topic

Author Message

thomasg(at)infosysnetwork
Guest

Posted: Wed Jul 13, 2011 11:19 am Post subject: Prop not cycling during run up

Recently the time it took for me to see RPMs drop when cycling the prop back during run up increased. It use to be almost instantaneous, but then I noticed 6 -10 seconds. Today cycling the prop had no affect other then seeing a quick,  slight drop in oil pressure when pushing the prop forward.



The prop acts normal otherwise,  getting up to red line on take off and cycling while in flight. 



This is my first CS prop, so this is all new to me. I don't see anything leaking, but after flying I have a very light oily residue on the prop which is barely noticeable. 



Any ideas/thoughts?



CJ/Housai 285

- The Matronics Yak-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Yak-List

talew(at)bellsouth.net
Guest

Posted: Wed Jul 13, 2011 12:51 pm Post subject: Prop not cycling during run up

I had a similar problem on my cj years ago . The sleeve on the prop cable near 

the governor

was slipping . I tightened it up and cured the problem . 

There is a screen on the governor that you may want to check also .

Terry



---

- The Matronics Yak-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Yak-List

wlannon(at)persona.ca
Guest

Posted: Wed Jul 13, 2011 9:00 pm Post subject: Prop not cycling during run up

Thomas;



Terry's suggestion is very likely the problem.  Not uncommon on the CJ.

Have someone move the RPM (prop.) control through full travel while you 

check for any movement of the copper cable housing where it is clamped 

approx. 8" or so from the governor.

Any movement will mess up the RPM setting.



Walt

---

- The Matronics Yak-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Yak-List

dsavarese0812(at)bellsout
Guest

Posted: Thu Jul 14, 2011 4:45 am Post subject: Prop not cycling during run up

Both excellent points Terry.   Many people do not check the prop 

governor screen periodically.  If it becomes gunked up, no oil can pass 

through it to the prop hub piston assembly.



If the screen is clean and the cable sleeve is secure, remove the prop 

hub dome and piston and see if you can move the counterweights by hand.  

They should move freely with some amount of resistance.  But definitely 

they should move to full coarse pitch and back to fine pitch freely.  If 

they don't, you will need to remove the prop blades from the hub, then 

remove the hub from the engine.  Disassemble the hub completely and 

check the  flat bearings (2 on each side) for pitting and flat 

spotting.  You will be able to see flat spots on the bearing rollers and 

corresponding races where the bearing has been binding.  If the bearings 

look good, clean, re-grease and reassemble the hub and bench test for 

smooth operation of the counterweights.  Check the phenolic pieces 

inside the large castellated nuts and replace the seals that go around 

the phenolic pieces.   LIGHTLY polish the inside surface of the phenolic 

pieces with 320 grit wet/dry paper.  Replace the outside and inside 

seals on the hub piston.



When reassembling the hub, do not over-tighten the large castellated 

nuts that "squeeze" the flat bearing.  Over tightening the large 

castellated nuts squeezes the flat bearings and prevents them from 

rotating against their respective races.  Any questions, don't hesitate 

to telephone me.

Dennis



A. Dennis Savarese

334-285-6263

334-546-8182 (cell)

Skype: Yakguy1

www.yak-52.com

On 7/13/2011 3:48 PM, T A LEWIS wrote:

[quote] 



 I had a similar problem on my cj years ago . The sleeve on the prop cable near

 the governor

 was slipping . I tightened it up and cured the problem .

 There is a screen on the governor that you may want to check also .

 Terry



 ---

- The Matronics Yak-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Yak-List

wlannon(at)persona.ca
Guest

Posted: Thu Jul 14, 2011 11:29 am Post subject: Prop not cycling during run up

Hi Dennis;



Some comments on the work you describe for the blade bearing assemblies;

Before attempting to remove and dis-assemble these the propellor overhaul 

manual should be read and understood.

Things to check before you start:



1.  Are the "0" index marks lined up on the big nuts and the hub?

2.  Do you have the special tools?

3.  Mark the exact position of any balance weights - relative to the HUB. 

NOT to the big nut or to the seal packing nut to which the weights are 

attached.  There could be weights on both sides of the hub rather than just 

one side. That depends on the amount of VERTICAL imbalance that had to be 

corrected.

4.  Before removing the bearing assy from the hub loosen the grease seal 

packing nuts.  These are punch staked to the big nut which on removal could 

destroy the thread.  Carefully drill the stake indents just enough to remove 

the upset metal

5.  If it required excess force to rotate the blades it is possible there is 

corrosion on the blade ferrule where it contacts the micarta (phenolic) 

bushing.  Check for that.

6.  If all parts are serviceable re-assemble with lots of grease, 

preferably Aeroshell 5!   Install the grease seal and retaining nut but do 

not re-stake yet.

7. Re-install the complete assy. and  if the index marks were lined up or 

SHORT of lining up then line them up.

Blade torque should be measured at this time but the overhaul process 

requires that to be done individually with the interconnecting drive sleeve 

removed from the hub.  With the index marks found as above this should not 

be necessary.

If the index marks were BEYOND lining up then re-torquing should be done. 

It is entirely possible that the existing lock plates may not fit.  If so 

discard them and make new ones, do not loosen the nut.



8.  Tighten the grease seal retaining nut.  Check for a position to 

re-install the balance weight relative to your HUB marking.  Re-stake the 

retaining nut in new locations



Cheers;

Walt



---

- The Matronics Yak-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Yak-List

Display posts from previous:

	Matronics Email Lists Forum Index -> Yak-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum