chass

Hi,

Recently someone gave me a chopper with an OS MAX 61V engine in it. I think the chopper is damaged beyond repair but the engine is in good shape except for a broken exhaust pipe. Can I convert this engine to work in a plane easily? Whats involved?

I notice that it appears to have "rear" exhaust. Does that present any problems? Can I buy an exahaust for it so that I can use it on a plane?

Thanks,
Chass
ct

Steve Campbell2

I don't think that is a heli engine; sounds like a ducted fan engine to me. Naturally, I don't have that OS engine history site bookmarked here at work...

Still, as long as you can shoe-horn it in, and it runs okay, it should do just fine in an airplane. But if it is a DF engine, they are tuned for higher rpms, which might affect your mid-range transition, idle, etc.

Steve

ShempHoward

My Feedback: (3)

That would be the 61VF-H (ABC or ringed) for FAI or F3C competition. Its a rear exhaust
so you would need to get a header and pipe for it. Should be a good plane engine if you can work out the exhaust system.

chass

I'm pretty shure it is a heli engine! Its in a heli!

Shemp,

So is the front of the engine going to look like the front of a plane engine when I get it appart? Particulary the shaft where the prop bolts on? I imagine I may need a spacer or something.

I assume from your post that I will probably have to fabricate my own header pipe that turns in a U shape but that clears the prop . . .

Thanks,
Chass
ct

GMPheli

The shaft will be the same, it will probably be 1/4 inch instead of the usual 5/16, and it may not be long enough. Depending on the fan setup, you may or may not have a prop drive washer. If you need one, let me know, I probably have one, and maybe an airplane head for it too, if it is the same as an FSR head. BTW, what heli was it in?

Alan Angus
[email protected]

ChuckAuger

My Feedback: (12)

The VF had a 2-piece case...the front housing (where the prop mounts) can be put on either end of the case. It would be better to swap these around and have a rear exhaust engine than try to make a 180 degree header that points to the front. Just my opinion..

chass

GPHelli, I don't know how to identify it. I have a newer gyro for it that I will be selling. I'd like to sell the chopper but don't know what its worth. It may be better for parts. I looked it over again last night and its not damaged much at all. It needs new blades front and rear but is generaly intact. I think I would trade the choper and its engine with poorly repaired pipe (no gyro) for a comparable plane engine. That would probably be my best bet. That way I wouldn't have to change the exhaust all around.

Chuck, if I don't trade that sucker, I'll definitely turn it around!

Thanks,
Chass
ct

GMPheli

Could you post or e-mail some pics?

chass

GMPHelli,

I will try and post some pics later today or tonight.

Chass
ct

ShempHoward

My Feedback: (3)

The prop shaft is 1/4-28 and Alan is right that a 61FSR head should fit it but I would just save the money and use the heli head as is. Hopefully it still has the press on aluminum collet which was common to most OS BB engines right thru the SF period
which means all you will need to put a prop on it would be a prop washer and a 1/4-28 bolt as the collet acts as a prop drive washer as well. It will look fine on the front of an airplane
but you may not have enough shaft to properly fit a prop on follwed by the washer and lock nut. I would check that first off before making any further investment in it.

chass

Thanks Shemp. I'll look at that before I buy anything for it.

GMPHeli,

Here is link to a pic. Can you identify it for me? Anyone?

http://www.rcuniverse.com/showthread...4903&forumid=8

Thanks,
chass
ctt

ChuckAuger

My Feedback: (12)

Your engine is already configured as a rear exhaust... No idea about the heli.

chass

Chuck, yes you are right. When I got home I realized that my conception of the setup was reversed! All the better I guess. Still I think it would be better for me to trade it to someone for a plane engine.

chass
ct

ChuckAuger

My Feedback: (12)

There is a guy looking for a 61VF here:

http://www.rcuniverse.com/showthread...460&forumid=49

Don't know if he'd want a heli version, you might hit him up..

ShempHoward

My Feedback: (3)

I really think you'll be OK using it in an airplane if you can fit a prop on it. Macs Mufflers will probably have a header and pipe for it as well.

chass

Shemp, ok you've convinced me to give it a try.

I'll remove it today.

Chass
ct

ChuckAuger

My Feedback: (12)

The 61VF was a great engine..if yours is in good shape, it will be as fine an engine as most made today. Read the link I gave to the guy wanting one..they are still very much sought after. If it was mine, I'd have it out and on a plane by now LOL.

downunder-RCU

From the OS engines timeline...
http://www.osengines.com/history/osm...x-61vf-abc.jpg
http://www.osengines.com/history/osm...max-61vf-h.jpg

If you open up each link in seperate windows then switch between the two it seems the H engine does use a smaller prop shaft (can't really tell if it's a different length though). But even if it's too short to mount a prop then that's no problem either. Fox makes T nuts which simply means drilling out the prop to 3/8".

The VF's in all sizes are marvellous engines....why OS would stop making them is beyond me.

ChuckAuger

My Feedback: (12)

Yep, downunder has it right..the aircraft version has a 5/16" thread, and Shemp has it right, looks like the heli has a 1/4" shaft.

The crank on the aero version is slit for a woodruff key, but uses a tapered collet. It wouldn't surprise me if the heli version utilizes the woodruff key, but I guess it would depend on the clutch/fan of the heli..kinda either/or.

A buddy sold a NIB RF-H a while back, and it definitely had a woodruff key in it.

Razor-RCU

My Feedback: (50)

I can only relate my experience with an old OS-50FSR heli motor-

I was skeptical when I got it (In a trade on RCU) but it is a great running engine- I used a Pitts muffler and it idled well, transitioned instantly, and had great top-end!

Go for it!

I know this is a different engine but my heli FSR screams like a Rossi!