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Prop governor adjustment Question

Stockmanreef

Well Known Member
I am in the process of adjusting the arm of the prop governor. What is the best way to do this.

1. take off the arm and adjust to the correct position?
2. loosen the nuts on the head and rotate?
3. the Hartzell prop governor installation guide says to use CM311 thread lock on the bolts for the head. What is this material? Who makes it? Is there a loctite equivalent?

Thanks
 
You should have enough adjustment range using the adjustable stops on the governor - during Phase I. You will have some additional lattitude with the bracket clamp nuts, and the rod end bearing. Initial adjustment should be based on cockpit lever control limits. Make sure you can get the full range of motion (stop to stop) from the cockpit. Leaving a little range of motion on each end from the cockpit allows minor FWF adjustments during phase I.

I used blue locktite on the fasteners. That’s the color of what was on there to begin with from Hartzell.
 
well based on the plans, there the 50 % mark should be 90 degrees to the bracket. Mine is not even close. I put on the bracket and then loosened all the screws and the head did not move. I ws not forcing any thing. If I can remove the arm, then that would be easier, but this it needs to be re-torqued. This may or may not be easy to torque. This its why I would prefer to loosen screws and move the head.

Does this make sense?
 
This may or may not be relevant, but, on my -10 with Hartzel governor, I had to: remove the screws completely (keep pressure on the end, an internal spring will try to push it apart); rotate the end of the governor; re-insert the screws.
 
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With my luck if I tried that trick, it would come apart. Maybe I will try it anyway. First I will loosen again to see if I can get the head to move.
 
On mine, I was able to move the head with the screws loosened but not removed. I also took the short lever arm off and installed a longer one. All this involved was removing the nut holding it on. The short lever that came with it, along with a powerful return spring required me to lock the friction lock on my quadrant to hold the set RPM on my RV8. This made it impossible to move the throttle, since the whole quadrant was now locked. The longer lever arm fixed that problem, also gave me a better range of motion.
 
Not all governors are the same.

On many you can rotate the control head with the screws just loosened.
As already mentioned (if I remember correctly) the Hartzel does require that you full remove the screws.
 
well I have the governor in place. The service letter says to torque down to 18-20 lb pounds. I assume that one needs to use a crows foot to do this.

Questions:

1. should I try to move the head to the correct position before torquing down the bolts that hold the governor in place or do I have to torque down?
2. Should I wait to torque down nuts and adjust the arm until after the engine is hung? Would it be easier to torque down at that point?


Thanks
 
My Hartzell governor does not require you to remove the screws to move the head in a limited range (maybe 15 degrees). If you want to move it more than that, you?ll need to remove the screws and rotate the head to the next slot in the direction you need (I did that). Once those screws are inserted in those slots, you have a range of movement. Make sure you put new blue locktite on these screws if you move them. This movement affects the torque applied to the lever arm by the push-pull control. Try to make this lever arm movement at the midpoint range on the lever arm at the midpoint range on the cockpit lever/control for the prop. The return spring is rather strong (to fine pitch) on the newer Hartzell prop governors, and a vernier control is a plus here. That?s why a longer lever worked for me (less leverage on the return spring).
 
The return spring is rather strong (to fine pitch) on the newer Hartzell prop governors, and a vernier control is a plus here. .

Sorry for the thread drift here. However, I am about to install my hartzell governor in a week and am new to CS props. I thought the spring pulled the arm against the adjustable stop and this was the max RPM limit / finer pitch and that you pulled against that spring to bring the prop RPM down/courser pitch.

Did I understand that wrong?

Larry
 
I am in the process of adjusting the arm of the prop governor. What is the best way to do this.

1. take off the arm and adjust to the correct position?
2. loosen the nuts on the head and rotate?
3. the Hartzell prop governor installation guide says to use CM311 thread lock on the bolts for the head. What is this material? Who makes it? Is there a loctite equivalent?

Thanks

Ok I dont get it. Why arent you calling the Hartzell tech line to ask these questions?
 
Larry - you are right. You are pulling to coarse pitch/low RPM against the return spring. If the cable breaks, the governor will move the prop to fine pitch/high RPM. With the strong spring and short lever arm that came on my Hartzell governor, the spring would move the prop lever to high RPM unless the friction lock was locked down pretty tight. Problem with a 3-lever throttle quadrant on an RV8 is that when you lock the quadrant, all 3 levers are locked - you can?t move the throttle easily. The longer lever I installed on my Hartzell governor reduced the leverage of that return spring for the prop control to the point that this didn?t happen.
 
FWIIW: My buddy and I both installed throttle quadrants in our RV-14As, because we have flown with throttle quadrants in other aircraft for many years and are likely untrainable. Unfortunately, we quickly discovered the prop lever would creep unless the friction lock was locked, which locks the other levers, too. We contacted Hartzell and were told we could join an evaluation program where they would install a weaker governor spring. We took them up on their offer and, now, our prop levers behave properly with no tendency to creep. :cool:
 
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