Conversion to C/S, Lyc O-360 A1A

[rvsxer]

I am finally switching to a Hartzell prop on my RV-6. The trusty Sensenich is coming off. I am not going to go into great detail on the conversion (Brian Chesteen did that a while back - thanks, Brian!) but I thought I'd post some information that I found hard to come by as I complete the project.

First, my O-360 is a narrow-deck ("standard flange") engine from a 1959 Mooney M20A. I bought the core with the governor adapter but the governor oil line was aluminum so I chucked it. Lycoming S.I. 1435 gives information regarding conversions to and from C/S operation. The S.I. lists part numbers for the oil line, 3 numbers for the narrow-deck engines. No idea which one fits my engine. Nobody (including Lycoming) seems to know. Long story short - the Lycoming #75167 for the wide-deck engines fits with minor tweaking. mustangbob51 helped me with that (thanks again!) The nose case fitting is an AN822-6 steel 90 degree elbow. The governor adapter fitting is an AN823-6 steel 45 degree elbow (pipe thread in the adapter), or Lycoming #74070 (straight threaded adapter). Some of the early engines had a -5 line and fittings so you'll be converting to -6 for the flared size.

I plan on adding to this post as I find things that might be helpful...

[RONSIM]

for the same engine --- just had a new one made because the original one was getting some years on it.

Ron

[rvsxer]

If I hadn't found this steel line I would have gone with a flex line. The Lycoming S.I. authorizes a flex line, too.

[rvsxer]

There is a likelihood your Hartzell governor will arrive with the control arm and backplate clocked wrong both for the arm and the Van's cable mount bracket. Here is a link with pictures: http://www.vansairforce.com/communit...tzell+governor
There are 12 holes in the governor body for the six socket-head backplate screws so you can turn the whole backplate and place it exactly where you need it so the control cable rod end doesn't interfere with the stops (this is only if you want to attach the rod end between the arm and the housing). You can then detach the arm from the shaft and clock that where you need it. Worked very well for me.

[N941WR]

How do you know which hub fit's your O-360?

I am dreaming of a McCauley hub for my ECi O-360 and have no idea how to find out what will and will not work with my engine.

[rvsxer]

Originally Posted by N941WR

How do you know which hub fit's your O-360?

I am dreaming of a McCauley hub for my ECi O-360 and have no idea how to find out what will and will not work with my engine.

Bill,

I checked Lycoming S.I. 1098K and asked our local engine shop "If I put these bushings in will my Hartzell C2YK ("K" flange) fit?" and they said yes. It fit. I would check with a prop shop, mention the S.I., and ask if a McCauley prop will fit.

[rvsxer]

Well the prop is on, and the ground tests are complete. Waiting on the weather now. Some more notes:

1) The Hartzell was a little less than 1/4" shorter than the Sensenich, from the flange to the aft spinner bulkhead, so I had no clearance between the cowl and the spinner. I decided to add a few large-diameter washers between the engine mount and the firewall. No other clearance issues surfaced after the change, and the alternator pulley still clears the cowl.

2) Christer Stenstrom here at SteinAir showed me a neat trick for changing the blade pitch for fitting the spinner. Just plumb a shop-air regulator or a compression tester into the governor oil line at the nose case. Turn it up to 20-30 psi and the blades go to full pitch.

3) I used Van's prop control cable and bracket, and put the firewall hole in the plans location. Worked perfect.

I hope this helps those of you doing this change. The best way to do this is, of course, while the plane is being built.