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Prop governor problems

Avengerboss

Well Known Member
Got a great story and I hope VANS reads this
Just finished my RV10 and started phase 1 flight test first takeoff prop RPM went to 2860!!!! Holy **** I thought, that IO540 I had built by Corona Engines was powerful. So figured I just need a little adjusting on the new Hartzell Govenor I bought thru VANS harness that 300hp. After many attempts I could not get the rpm down. I could only do manually.
So I called Hartzell, told them I bought the prop and Govenor thru Vans and can't adjust the rpm down to 2700 on takeoff. I have to say the guys at Hartzell were amazing and worked with me thru this whole ordeal.
We tried adjusting the prop itself, reclocking the Govenor but nothing worked?? Grrrrrr!!!! Very frustrating!!!!
Made another call to Hartzell , they were scratching their heads also.
Well one the them asked me what engine do I have ? A "Narrow Deck" or a "Wide Deck" IO540. I told them I have a "Narrow Deck" ! And he verified I purchased a -32 Govenor from Vans (as listed for the IO540).

Ahhhhh ha!! He says, you got the wrong Govenor. You should have a -26. Reason is the narrow deck and wide deck 540's have different Govenor drive ratios.
VANS lists both -32 and -26 however they are listed as the -32 for a IO540 and the -26 for the O540. No mention of wide or narrow deck (obviously a wrong way to list the two since injection or carberator means nothing relating to prop Govenor drive).
I call Vans hoping to get a exchange to the correct Govenor since I felt we were both at fault here. I was hoping for some help. Nope!! Sorry, you used it we can't exchange it and that was it!! $1300 wasted. My View is VANS should be listing the Govenors correctly.
Hartzell to the rescue. The recommended me to True Speed Areo Govenors at Van Nuys airport and they can "reclock" my -32 Govenor to a -26. So I called,
Martin, he was great he worked with me and Hartzell to reclock the internal valve to give me the 2700. $265 later I have a perfect Hartzell Govenor. Awesome.
 
Does re clocking change some valve port opening? I never been inside of one but one would think that if the ratio is different, the governor internal RPM is different? Just trying to comprehend what is going on inside one of these....
 
How long was it at 2860? I suggest you take a look at Lycoming mandatory SB 369L on overspeeds as by my math that's just over 5% and could drive some inspections. YMMV.....
 
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Prop Govenor

Overspend was only seconds at best before I propped it down .
Don't know anything about the internal workings the only clocking it did was external on the slotted face plate.
 
According to Hartzell this morning, their governors can be set to widebody or narrow body ratios with a simple change internal to the unit plus clocking if required. It was described as a plastic part removed from one hole and plugged into another. Simple, but should be done by an authorized shop.

They also told me that they believe that there has been a newly reported additional failure of an MT governor.
 
According to Hartzell this morning, their governors can be set to widebody or narrow body ratios with a simple change internal to the unit plus clocking if required. It was described as a plastic part removed from one hole and plugged into another. Simple, but should be done by an authorized shop.

They also told me that they believe that there has been a newly reported additional failure of an MT governor.

Christ!!!!:mad::mad: I wish they would have told me that when I was asking them about the correct model for the narrow and wide decks. I've already sent the S-1-32 I got from Vans back for a refund. What a goat rope this whole experience has been.
 
Overspend was only seconds at best before I propped it down .
Don't know anything about the internal workings the only clocking it did was external on the slotted face plate.

If you have engine data I'd recommend taking a close look and then bump that up against the SB--over 5% for more than a few seconds gets into inspection territory based upon how I read the SB, but then again I'm not an A&P or engineer so take my advice with a grain of salt.
 
True Speed Aero are the guys for your Govenor and the internal reclocking. The shaft has to be redrilled and reset. they did mine perfectly!:D
 
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