converting from fixed pitch to constant speed

[jeff beckley]

I am kicking around the idea of converting my RV7 to constant speed.
I have a lyc A3A hollow crank. I need some advise as to how i would go about this. Like how do I go about converting the crank and does it have to be removed to install the rear plug. What to look for in buying a used setup. AD's and things. Anything would help me .

[jabarr]

See Lycoming SI 1435--

http://www.lycoming.com/support/publ...dfs/SI1435.pdf

[charger81]

I would be very interested to hear why you want to switch. I see FP/CS constantly debated but it is usually more about defending the choice made. You obviously have made the choice to switch so it would be great to hear what about the FP you don't like and why you think CS will be better (as it pertains to your "mission").



Thanks in advance!

Mike

[L.Adamson]

Originally Posted by charger81

I see FP/CS constantly debated but it is usually more about defending the choice made.

IMO, many go with the fixed pitch prop because of the initial expense of the constant speed.

I went with the C/S right up front because I knew of all the advantages before hand. I had switched from F/P rentals to C/S rentals a long time ago. There is no way that I would have been content with a fixed pitch RV, and purchasing the Hartzell was probably the number one priority above all else.

Better takeoff performance. Much more choices for landing. Quieter in flight.
Excuses such as C/S maintenance are only that. We re-grease during the condition inspection, and that's about it.

If you just transition from a Cessna 172 or Piper Warrier, to the RV, then you probably wouldn't realize the vast difference between the two props. But if you had flown something more complex, then the difference is quickly obvious...

My choice was made from prior & positive "experience". And BTW, I know of no RV owner around here.............who wouldn't prefer a C/S over their F/P. Just stating the facts.

L.Adamson ---- RV6A Hartzell C/S

[Jerry Cochran]

Anyone know the all up weight diff between an alum Sensenich and a two blade Hartzell? I came by a "used" Sensenich and was surprised how heavy it was...

[Radomir]

It should be around 16lbs.. (Sensenich is 40 and Hartzell around 55 or so)... but you'll almost always gain more if you convert after a while.. somehow planes gain weight over time

Been through that process recently.. it wasn't all that bad...

[sf3543]

Jeff
Feel free to give me a call to discuss this project. I did it on my RV6, but the discussion is more than I care to type.
210 289-3984

[jeff beckley]

Right now what i am most interested in is installing the rear plug. What is the procedure for that?

[N941WR]

Originally Posted by jeff beckley

Right now what i am most interested in is installing the rear plug. What is the procedure for that?

There is a Lycoming document that cover how to do that.

In short, I made sure the inside of the crank was clean, put a little RTV on the plug, slid it in place - bubble out, took a long square piece of oak that just fit inside the crank, grabbed a four pound sledge hammer and creamed that thing. The trick is to depress the bubble so it pushes the plug outward, sealing the crank.

If you have one of those newfangled cranks with tubes that cross through it, you might have to modify that wood block a bit or use a long socket extension.

[Sam Buchanan]

Originally Posted by N941WR

There is a Lycoming document that cover how to do that.

In short, I made sure the inside of the crank was clean, put a little RTV on the plug, slid it in place - bubble out, took a long square piece of oak that just fit inside the crank, grabbed a four pound sledge hammer and creamed that thing. The trick is to depress the bubble so it pushes the plug outward, sealing the crank.

If you have one of those newfangled cranks with tubes that cross through it, you might have to modify that wood block a bit or use a long socket extension.

A crank with the oil tube in the center of the bore really does complicate matters. My hangarmate recently made the switch and before all the old rear plug was cleared out a cylinder had to be removed to pick out the remains of the rear plug that had been pushed down the crank. Be sure you have somebody close by who has experience with working around the oil tube if your engine is so equipped. Getting the old rear plug out is the biggest hassle.

Having said that, Bob loves the C/S prop.