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Converting from FP to CS shopping list

lucas2696

Well Known Member
Friend
I've decided to take the plunge and convert from my Sensenich GA prop to a constant speed, 2 blade aluminum Hartzell on my O-320-D1A powered RV-6. There aren't many options for CS props for the O-320, there's basically the "paddle blade" metal Hartzell, the WW300 3 blade, and 2 or 3 blade MT composite propellers.
My engine was delivered from Lycoming configured for CS and was converted to FP at installation, by means of removing the governor drive, oil line, puncturing the inner crank plug, and installing an expansion plug. I have the original governor drive but nothing else.

The reasons for this specific selection were:
1) by most reports the two blade Hartzell is one of the faster options and I don't want to sacrifice top end speed
2) my airplane is pretty tail heavy with the late model RV-8 sized tail and lightweight engine, so as much weight as can be put on the nose the better (especially non-dead weight)
3) far and away the least expensive option
4) typical inspection/OH schedule, basically *should* be good until the engine needs overhauled

So, I've located a prop, now I'm piecing together everything else I'll need to finish the conversion.
1) governor, I've decided on a PCU5000X through Flyboy Accessories for this
2) governor oil line PN 75167, Air Power has this for a "reasonable price", is there any reason to go with a flexible hose over the rigid tube from Lycoming?
3) replacement inner crank plug PN 61510, also from Air Power
4) control cable bracket, unfortunately both Vans and Showplanes are currently out of stock of these so I'll be on the lookout for those
5) control cable, probably source from Spruce, any tips on measuring for length?
6) manifold pressure gauge, I have a 2.25" hole in my panel above my tach that I could use for this, probably pick up a UMA electronic one, open to suggestions though
7) manifold pressure sender, mount and hose, mount from Showplanes is on the way, I'll get a hose from Aircraft Specialty once I know how long it'll be
8) spinner kit, this is one thing I've not done a LOT of research one yet, I assume most people use the Vans composite one, but I do like the look of a polished spinner, maybe get one from Cummins in Australia?
9) ????

I don't think that's an exhaustive list, but it's all I can come up with at the moment. Any input is appreciated!
 
Tom at TS flight lines also makes a stainless governor hardline to consider.. you’ll also need to secure it with the line clamp & hose, and adel clamp. Also if you are tired of the Lycoming price gouging on the oil plugs, you can add “SL” to their part number and get a cheaper Superior alternative from Spruce.
Do you have the oil line fittings from the governor drive and the angled steel fitting that goes into the engine case?
You are going to LOVE the acceleration from a CS prop.. it’s hard to imagine that people still build FP RVs.. just make sure you adjust out some of the braking by properly adjusting the low pitch stops..
 
Tom at TS flight lines also makes a stainless governor hardline to consider.. you’ll also need to secure it with the line clamp & hose, and adel clamp. Also if you are tired of the Lycoming price gouging on the oil plugs, you can add “SL” to their part number and get a cheaper Superior alternative from Spruce.
Do you have the oil line fittings from the governor drive and the angled steel fitting that goes into the engine case?
You are going to LOVE the acceleration from a CS prop.. it’s hard to imagine that people still build FP RVs.. just make sure you adjust out some of the braking by properly adjusting the low pitch stops..
I wasn't aware Tom offered those, will definitely hit him up.
Good call on the Superior plug, $10 instead of $50!
I've flown another RV-6 with a CS Hartzell, it was also an IO-360 vs my O-320, but yeah, it really puts you back in your seat. It's also the only taildragger I've flown where I experienced the torque/gyroscopic precession just from lifting the tail on takeoff. You had to consciously add copious amounts of right rudder while releasing backpressure or it would DART to the left lol.
 
You didn't mention if you already had the Manifold pressure fitting fir #3 cylinder. If not, Tom, TS Flightlines makes a nice one. He also makes a P-mag plumbing kit if you plan to swap at some point.
 
The 6 was designed for 320/FP, so I would probably try to keep the weight down.
PS: the MT is actually a wood blade not composite.
 
The 6 was designed for 320/FP, so I would probably try to keep the weight down.
PS: the MT is actually a wood blade not composite.
It was also designed with legacy engine accessories in mind that are a lot heavier than modern components, hence why so many RV-6s tend to be on the tail heavy side these days. The airplane only weighs 1015lbs, it can afford the extra weight.

PS: wood core composite is still composite. One of the oldest methods of composite construction actually.
 
The 6 was designed for 320/FP, so I would probably try to keep the weight down.
PS: the MT is actually a wood blade not composite.
Yeah but MT props are so slow.. it seems to me that every MT prop on an RV is nearly 10 knots slower than a Hartzell equipt one.. isn’t the MT blade wood AND covered with fg or cf? Isn’t that the definition of “composite”? You can argue that a wood prop IS carbon fibers!! Lol
 
I've decided to take the plunge and convert from my Sensenich GA prop to a constant speed, 2 blade aluminum Hartzell on my O-320-D1A powered RV-6. There aren't many options for CS props for the O-320, there's basically the "paddle blade" metal Hartzell, the WW300 3 blade, and 2 or 3 blade MT composite propellers.
My engine was delivered from Lycoming configured for CS and was converted to FP at installation, by means of removing the governor drive, oil line, puncturing the inner crank plug, and installing an expansion plug. I have the original governor drive but nothing else.
<snipped for brevity>

I don't think that's an exhaustive list, but it's all I can come up with at the moment. Any input is appreciated!

I’m about to start an almost identical upgrade as well. We have an O-320-D1A powered -6 but with the original tail (a ‘90’s build), and a Bernie Warnke ‘almost constant speed’ wood prop. I also would appreciate a little more weight on the nose. I changed the wood prop for a second hand Whirlwind Ground adjustable, and within six weeks of it being installed Hartzell issued the 25 hour hub crack check and bolt replacement SB. Having the ground adjustable let me see the benefits of a fine pitch when flying formation with that near instant acceleration and deceleration compared to the much coarser Bernie Warnke prop. I did miss going from having one of the fastest FP planes in the formation to losing 12-15ktas in cruise, (but my fuel burn went down correspondingly).

I elected to go with the following from Whirlwind/ Hartzell after many very early morning support and info seeking phone calls and emails to WW/Hartzell support.
WW 300-3B-B/A-70-S-R, Spinner & Bolts
Jihostroj P-920-032/A governor
According to reviews, opinions & articles the WW300 should give me better acceleration than the Hartzell BA prop, (which is not available for the O-320 anyway), and the same cruise performance. The few extra pounds it weighs shouldn’t add too much extra but will offset the smoke tank and smoke oil. We’re at 1053lbs/71” empty with the WW ground adjustable. I’ll re-weigh the aircraft properly after the WW300-3B is on to reset the +/- calculations.

Since I didn’t have the governor drive I trawled the O-320 B&D parts catalogue and came up with the following part numbers which I obtained through Suncost Aero Engines or Superior Aviation in Queensland, Australia. The parts manual shows two governor adaptor assemblies, 75153 and 75545 and corresponding stud lengths. I got 75153 and will see if it’s correct when I unseal the governor from its packaging. (Joel at Suncoast very kindly offered to swap the adapter assembly if the 75153 adapter doesn’t fit). I elected to go with the hard stainless pipe instead of the flexible hose as the latter is life limited.
0. ) Plug 1-3/4 OD Inner crank: pn: 61510
1. ) Oil line pn: 75167
2. ) 3/8 ID hose x1.00" long (pn: STD-1930)
3. ) Clip pn: 75765
4. ) 5/16 Plain washer (pn: STD-35)
5. ) 5/16" Lock washer internal teeth MS35333-41 typeA (STD-475)
6. ) 5/16"-18 Bolt x 15/16" long hex head pn: STD-1838
7. ) Clamp pn: LW-16266-25-38
8. ) Elbow steel 3/8" tube-1/4" NPT 90 degree MS20822-6
9. ) ELBOW, 3/8 flared tube & 9/16-18 str. tM., adj. 45° pn 74070
10.) O-ring MS29512-06
1. ) 68317 SHAFTGEAR, Prop. governor drive
2. ) 71596 WASHER, Accessory driven gear
3. ) STD-1221 RING, 13/16 dla. x 27/64 thick, Internal retaining
4. ) 68315 GASKET, Accessory drive adapter
5. ) 75153* ADAPTER ASSY. Prop. governor drive
5. ) 75545** ADAPTER ASSY. Prop. governor drive
6. ) 1102 PLUG, 1/8·27 NPT, Allen
7. ) 31C·16* STUD, 5/16-18 x 2.00 long
7. ) 31C·14*" STUD, 5/16-18 x 1-3/4 long
8. ) STD-1774 PIN, 1/8 dia. x 1/4 long
9. ) STD-35 WASHER, 5/16 plain
10.) STD-475 WASHER, 5/16 lock, Internal teeth
11.) STD-1410 NUT, 5/16-18 plain
13.) 72053 GASKET, Governor
16.) STD-35. WASHER, 5/16 plain
17.) STD-475 WASHER, 5/16 lock, Internal teeth
18.) STD-1410 NUT, 5/16·18 plain

Other parts from Vans:
CT BLUE VPROP 48. (Vans)
Bracket VA-153-PC. (Vans)
WASHER 5702-475-48 Z3. (Vans)
WASHER 5702-75-60. (Vans)
CT BEARING MW-3M. (Vans)
Parts from Aircraft Spruce:
Sphere steel grommet .240 p/n 05-01382
(& a bunch of restocking of general hardware etc.)


I already have a MAP gauge, and so the cockpit work will involve de-riveting the throttle/mixture knob sub-panel and remaking wide enough it to take the prop control. (Oh also most likely re-routing a bunch of wires that go to/from the Ray-Allen trim switch and trim position indicator in the centre console.

Don H
Sydney, Aus
 
Yeah but MT props are so slow.. it seems to me that every MT prop on an RV is nearly 10 knots slower than a Hartzell equipt one.. isn’t the MT blade wood AND covered with fg or cf? Isn’t that the definition of “composite”? You can argue that a wood prop IS carbon fibers!! Lol
Everything is a compromise, I may have given up 5 knots top speed but gained climb performance, lost 12 lbs, smoother and quieter.
I’m pretty sure your “it seems to me” is your opinion, not based on fact. I’ve had both the BA and MT on my plane.
Not to mention the 3 blade MT rocks in the looks department. :unsure:
 
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I've decided to take the plunge and convert from my Sensenich GA prop to a constant speed, 2 blade aluminum Hartzell on my O-320-D1A powered RV-6. There aren't many options for CS props for the O-320, there's basically the "paddle blade" metal Hartzell, the WW300 3 blade, and 2 or 3 blade MT composite propellers.
My engine was delivered from Lycoming configured for CS and was converted to FP at installation, by means of removing the governor drive, oil line, puncturing the inner crank plug, and installing an expansion plug. I have the original governor drive but nothing else.

The reasons for this specific selection were:
1) by most reports the two blade Hartzell is one of the faster options and I don't want to sacrifice top end speed
2) my airplane is pretty tail heavy with the late model RV-8 sized tail and lightweight engine, so as much weight as can be put on the nose the better (especially non-dead weight)
3) far and away the least expensive option
4) typical inspection/OH schedule, basically *should* be good until the engine needs overhauled

So, I've located a prop, now I'm piecing together everything else I'll need to finish the conversion.
1) governor, I've decided on a PCU5000X through Flyboy Accessories for this
2) governor oil line PN 75167, Air Power has this for a "reasonable price", is there any reason to go with a flexible hose over the rigid tube from Lycoming?
3) replacement inner crank plug PN 61510, also from Air Power
4) control cable bracket, unfortunately both Vans and Showplanes are currently out of stock of these so I'll be on the lookout for those
5) control cable, probably source from Spruce, any tips on measuring for length?
6) manifold pressure gauge, I have a 2.25" hole in my panel above my tach that I could use for this, probably pick up a UMA electronic one, open to suggestions though
7) manifold pressure sender, mount and hose, mount from Showplanes is on the way, I'll get a hose from Aircraft Specialty once I know how long it'll be
8) spinner kit, this is one thing I've not done a LOT of research one yet, I assume most people use the Vans composite one, but I do like the look of a polished spinner, maybe get one from Cummins in Australia?
9) ????

I don't think that's an exhaustive list, but it's all I can come up with at the moment. Any input is appreciated!
I went through the same conversion a while back with the same engine on a RV9 (not A). Despite the cost and complications it is a worthwhile project especially if you operate at DA's of 5000 feet and above.

I went with the Wirlwind 300. Top speed was unaffected. Take off and climb out is a lot better.

I used the standard Vans cable. The governor bracket from Vans and Showplanes had to be modified.

I had the oil line installed at overhaul, the flex line might be easier to install on a already installed engine. Otherwise I'd prefer the stainless steel line.

The Wirlwind came as a complete kit with spinner, bulkhead etc.

I replaced a composite GA Sensenich so CG remained about the same.

Good luck with your project, I'm sure you will be happy with the results.
 
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