[brister]

Can A McCauley constant speed prop be used on an RV-7? All I see used are hartzell any reason?

 

[dan]

Take a look at the TCDSs (type certificate data sheets). Mooney used McCauley props on IO-360s for a while there. You can probably find a combo that gets along and that a DAR won't scoff at.

I remember reading something about McCauley hubs possibly causing fit issues, but I don't have specifics on that. Hopefully somebody who knows the deal can chime in if it's really an issue. Although...a "fit issue" can sometimes equate to a "custom airplane" if that floats your boat...

 

[Aden Rich]

Props

I have seen one McCauley prop on a RV-6 and the guy said it was a major pain to get it to fit. They have a totally different mounting style and hub that is a lot bigger than the Hartzell. Unless you can get one for cheap, it just isn't worth the extra effort. Plus, there is a lot of flight data on the Hartzell and the numbers are there if you need them. I have not seen any numbers for a McCauley.

 

[osxuser]

The reason you don't see a lot of McCauleys on these airplanes is because they don't try to make the experimental market theirs. The don't sell new any kits for aircraft such as the RV. There are some things to consider:

Mooney 201 and Cessna Cardinal RG both use a similer prop on the IO-360 A1B6 or A3B6. Of course to get this to work well, you will need to use the spinner from that aircraft as well. The little bitty VAN's fiberglass spinner doesn't fit I don't think. The spinner bulkhead combo from the Mooney or the Cardinal is a bigger diameter, therefore you will find yourself needing to modify the cowl to some significant degree to get the fit.

The advantages, if they can be call that:

*Unique, not many people have this combo, maybe conversation.
*COULD be faster, but I doubt it would beat the BA Harzell
*Lower overhaul cost, Lower parts count, a ONE piece hub.
*Spinner looks NICE on RV's

There was a Turbo -8 in SportAviation a couple years ago that used a three blade McCauley. Obviously the owners weren't worried about weight with the 3 blade (At 73.5 LB installed weight) and the turbo, but the McCauley longer pointed spinner looks WAY better than Van's IMHO .

If you have a deal on one, I'd go for it, otherwise, stick with the tried and true. It's hard to be the Hartzell BA value.

 

[rickrv8]

It Can Be Done

The IO-360A3B6D I'm flying on my -8, which is from a Mooney 201, came with a McCauley prop. In order to use this prop I had to make a couple of modifications.

First of all, the Mooney spinner backplate diameter that came with the prop was too big and Van's constant speed spinner backplate would not work. However, there are at least two airplanes (Maule & C210) that use the McCauley prop that have a 13" (proper size) backplate. Accordingly, I purchased a C210 backplate and used Van's spinner. The C210 backplate is very pricey. In addition, the flange angle is a bit different (less) than Van's spinner and creates a small gap at the back of the spinner. I simply filled the gap with resin and flox. Not a big deal. Also, the McCauley hub requires a different type of forward bulkhead. There a couple of solutions. I made one out of fiberglass. The front of the hub fits inside this permanently mounted bulkhead. Or you can purchase a removable front bulkhead. I learned about this option after I already made my bulkhead. I don't recall the details but they may be in the rvlist archives.

The second modification is the cowl itself. The back edge of the McCauley bulkhead is located further aft than the Van's bulkhead. Therefore, the cowl must be mounted further aft. I don't recall the actual difference, but I believe is was less than one inch. This was no big deal when mounting the cowl but if you later decided to go with a Hartzell you would have one heck of a gap between the spinner and the cowl.

There may however, be a much simpler solution. After I made all these modification I decided I wanted a Whirlwind prop. At the time the 200C prop was available (the 200RV hadn't been released) and it uses the McCauley hub. I believe the 200RV also uses the McCauley hub or a clone thereof. The point is that these props come with a spinner designed for an RV. You may be able to purchase their spinner assembly and use it on an existing McCauley prop. You would save some work; it probably wouldn't cost much more than the C210 backplate; and you wouldn't have to modify the cowl.

 

[mannanj]

McCauley Prop

I too have an IO-360-A3B6D with a McCauley prop from an Arrow. Basicly the same prop as the Mooney. I used the Van's fixed pitch spinner and backplate.

The rub comes with the front stabilizer support. The McCauley uses a ring like device with a flange that slips over the front dome of the prop. The flange fits tight against the spinner with no screws. I found a ring that came close to fitting at my local prop shop and a machinist friend trimmed some off the back side and turned down the flange thickness to where it finally fit.

The Hartzell front support is bolted to the front of their dome, then has screws through the spinner. The back plate fits 2.25 in forward of the prop flange; where the back plate for the McCauley fits between the prop flange and the crankshaft. (Unless you have a spacer to move the prop forward.)

Hope this helps some. PM me if you have more questions. With 80+ hrs. now, I love my engine-prop combo. May even be faster than the Hartzell.