Prop governor follies

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Rich
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Re: Prop governor follies

Post by Rich »

Here are the marks for that 3mm and the gap it produced at the high RPM point. This the procedure in the AMM.
IMG_0651.jpeg
IMG_0652.jpeg
Below is after sliding the clamp up the cable and tightening everything down. If it turns out to not be quite enough a fine adjustment can be made by adjusting the cable housing position.
IMG_0653.jpeg
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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mhoran
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Re: Prop governor follies

Post by mhoran »

Went out yesterday with the intention of making this adjustment. However, it was around 60 degrees and I found the prop lever was able to pull the governor arm back against the high RPM stop without issue. On takeoff we were able to reach 2660 RPM, just within spec. We didn't have time to perform a second takeoff, so I'm not sure if this changed when the engine was a bit warmer. But now I'm wondering if we have a different issue with our governor.
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Rich
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Re: Prop governor follies

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mhoran wrote: Tue Feb 21, 2023 2:54 pm Went out yesterday with the intention of making this adjustment. However, it was around 60 degrees and I found the prop lever was able to pull the governor arm back against the high RPM stop without issue. On takeoff we were able to reach 2660 RPM, just within spec. We didn't have time to perform a second takeoff, so I'm not sure if this changed when the engine was a bit warmer. But now I'm wondering if we have a different issue with our governor.
When I got the governor installed I found the high-RPM stop screw itself needed to be adjusted, as it limited the RPM to around 2650 RPM.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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Rich
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Re: Prop governor follies

Post by Rich »

One other thing to check. After my engine work in 2015 I found the shop had routed the prop control cable over the top of the front engine baffle material, instead of underneath. This prevents the baffle material in that area from seating against the top of the cowling in flight, as intended.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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Re: Prop governor follies

Post by mhoran »

Rich wrote: Tue Feb 21, 2023 3:09 pm When I got the governor installed I found the high-RPM stop screw itself needed to be adjusted, as it limited the RPM to around 2650 RPM.
I have seen 2700 RPM once, so I don't think that's it. I suppose it could also be the tachometer. I think the issue is benign enough that I will wait to poke any further until my annual in May.
Rich wrote: Tue Feb 21, 2023 3:12 pm One other thing to check. After my engine work in 2015 I found the shop had routed the prop control cable over the top of the front engine baffle material, instead of underneath. This prevents the baffle material in that area from seating against the top of the cowling in flight, as intended.
Fortunately the cable is routed correctly.
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Steve
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Re: Prop governor follies

Post by Steve »

Flew today and changed the oil afterwards - here are a couple of photos of the High RPM and Low RPM stop screw positions on my airplane:
High RPM stop screw
High RPM stop screw
Low RPM stop screw
Low RPM stop screw
Rich - although I didn't measure the exact distance, it appears that my Low RPM stop screw is the same distance from the governor lever when the PROP control is pulled all the way back as yours is.
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Re: Prop governor follies

Post by dmloftus »

MT rebuilt my prop about 10 hours ago. Did not elect to rebuild the governer. MT said it would take 10-15 hours for the prop to loosen up, it tends to lag on the low side for a few seconds after pushing the prop lever forward. Still, I'm only getting about 2650rpm on takeoff roll. I'm debating whether I should adjust the high rpm stop screw, but hesitant in case the prop continues to loosen and risk over rpm down the line. Thoughts?
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Rich
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Re: Prop governor follies

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dmloftus wrote: Mon Mar 20, 2023 7:59 pm MT rebuilt my prop about 10 hours ago. Did not elect to rebuild the governer. MT said it would take 10-15 hours for the prop to loosen up, it tends to lag on the low side for a few seconds after pushing the prop lever forward. Still, I'm only getting about 2650rpm on takeoff roll. I'm debating whether I should adjust the high rpm stop screw, but hesitant in case the prop continues to loosen and risk over rpm down the line. Thoughts?
The first thing to do is be sure the lever is all the way up against the upper RPM stop. If so, I'd think about readjusting it. But are you sure the shop didn't fiddle with the governor or cable adjustment in any way?
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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Rich
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Re: Prop governor follies

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More weirdness. My MT prop never did exhibit the sluggishness to rev up after the recent overhaul - until today :scratch: It’s not as bad with full throttle application, but during runup it was realllllly slow to return to the 2000 RPM point. The only difference is that today was a good 30 degF higher ambient temperature than it has been in at any point since the overhaul was done last year.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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Re: Prop governor follies

Post by dmloftus »

Rich wrote: Thu Apr 27, 2023 12:12 am More weirdness. My MT prop never did exhibit the sluggishness to rev up after the recent overhaul - until today :scratch: It’s not as bad with full throttle application, but during runup it was realllllly slow to return to the 2000 RPM point. The only difference is that today was a good 30 degF higher ambient temperature than it has been in at any point since the overhaul was done last year.
30 hours since MT overhauled my prop and I have the same issue. Cycling the prop at runup takes about 10-20 seconds to return to 2000 RPM. When I push full forward on the takeoff roll, I don't notice nearly as much lag. It gets to about 2670 RPM within seconds. But mid power levels it takes substantially longer. MT advised that it would be tight for 10-15 hours as the bearings fully seat. While it's a bit better than immediately after overhaul, I'm thinking 30 hours is definitely on the high side of that range to return to completely normal operation. While it's not really an issue operationally, I have the nagging concern about a delayed ramp in RPM in a go-around situation. So I try to remember to push the blue knob full forward earlier in my final approach than I used to.
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