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Which Prop Governor?

ppilotmike

Well Known Member
Which prop governor should be used with the IO-540 for the RV-10. I seem the remember there being problems with certain choices that didn't really perform well for people. I plan on using the standard Hartzell 2-bladed CS prop and buying the engine/prop combo from Vans. However, I'm under the impression that Vans doesn't provide the governor..
 
I've been very pleased with my PCU5000X. I have nothing but bad things to say about MT after my MT gov (which the PCU replaced) self-destructed in-flight.
 
I'm also a bit confused on which model I need to buy. Planning PCU5000X, but rotation and arm angle have me stumped.
 
I'm also a bit confused on which model I need to buy. Planning PCU5000X, but rotation and arm angle have me stumped.

I got pretty frustrated with the staff at PCU. I talked to two different people there and they weren't very helpful. Perhaps I just needed to find the right person. Jihostroj designs and manufactures the governors in the Czech Republic and they have helpful information on their website. https://www.jihostroj.com/en/propeller-governor.html

On rotation, you just need to know if the governor's arm needs to be on the top or bottom and if it needs to rotate clockwise or counterclockwise when the cable is pushed in for full RPM. I could actually swap the cable bracket and use either clockwise or counterclockwise rotation, so in the end, rotation made no difference. Your application may be different. Arm angle makes no difference either, since you will likely have to adjust the angle by removing the safety wire from 6 small screws and adjusting the clock angle to fit your cable and cable bracket. They want the angle to preset it to when it ships from the factory, but the chances of it working out of the box are slim.

My governor is on the back and this photo isn't great, but you might get the idea. For this bracket/arm orientation, you would want clockwise. Flip the bracket and rotate the arm, and counterclockwise would work.
 

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PCU5000X

I've had almost 100 trouble free hours with my PCU5000X. Not sure how price compares anymore but at the time I bought it it was a group buy and made sense over the hartzell based on price. The model I purchased was the P-520-029/A-947. Here is a link to the experimental application chart pdf https://www.aircraftpropeller.com/pdf/EXPERIMENTAL-APPLICATION-CHART.pdf.

On their order form I left the values empty for the control lever angle and rotation. Also the Pressure to increase/decrease and the counterweighted prop checkboxes. Seems RV-10 and IO-540-C4B5 was enough for them to get it right. You end up re-doing the safety wire on the 6 screws anyway to get clocking perfect for the prop gov cable.
 

I pulled my MT governor (which was "hunting" rpm anyway) after I saw what MT did to Todd's engine (and others). Especially egregious is MT's counterfactual service bulletin, claiming the exploding governor problem was restricted to modified engines when they know that's not true.

I've been very happy with the PCU 5000. Rock solid governor speed. And it'll allow even lower prop governing speeds than the Harzell will - handy in the case of engine failure and a blue knob pull to extend glide. I believe Hartzell stops at 1500 rpm (not a problem - just a design choice AFAIK).
 
+1 for the hartzell from vans...zero issues and rock solid, no hunting at all...

+1

Mine has been reliable and holds RPM VERY stable.

Be aware the different governor configurations are required for the ND vs WD 540, as the gov drive ratios are different. Vans only offers the hartzell version for the WD. The S series can be modified in the field, if you take precautions.

Larry
 
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I've been very happy with the PCU 5000. Rock solid governor speed. And it'll allow even lower prop governing speeds than the Harzell will - handy in the case of engine failure and a blue knob pull to extend glide. I believe Hartzell stops at 1500 rpm (not a problem - just a design choice AFAIK).

That is interesting. Have you tested how low RPM the PCU will govern and/or the effect on glide ratio when pulling the blue knob?

I can confirm with the Hartzell, the blue knob has no effect when at engine off glide ( 85-90 kts, prop wind-milling at 1100-1300 rpm ). Just curious what the PCU can do.
 
Thanks everybody! Any idea what the cost savings might be to go with the PCU 5000 over the Hartzell? If it's not significant, I'll stick with the Hartzell.
 
Prop Governor

Another happy Hartzell user here. Got it from Vans with the kit and have had no problems in 500+hrs.
 
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