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What props are the other flying Rotax planes using? My 60" 3-blade Warp Drive has been fine on the Onex, but it's quite a compromise. I had the pitch set toward the fine end originally, and was seeing over 1100 ft/min climb, but maybe only 115 mph in cruise. I've added a couple degrees of pitch since then, and climb is down to maybe 850 ft/min, though cruise is easily 130 mph TAS, and as high as 145 mph at 5750 RPM. I should really add another degree of pitch and try that, but I'm not willing to give up any more climb.

Since I require such a short prop, that rules out all the "pretty" props that are out there. They often have about a 68" min length. I've been really tempted to give the Ivo medium prop a try for a couple reasons. First, I'd like to see if it performs better as a fixed pitch, but it would also give me the option to go to in-flight adjustable. A 3rd reason is for some extra engine protection if my limited prop clearance ever catches up with me. Warp Drive props are practically bullet proof, which makes them great for pusher engine installations, but if I ever had a prop strike, I'd probably rather it be with something less durable.

Otherwise, the engine and Onex are doing great. I'll be working to finalize inlets and outlets on the cowl now that we're having some 90+ degree temps. No problem with cooling at all, but I need to make it less ugly and reduce the drag some.

Cheers,
Rusty

I should receive my M-T prop this week and be flying this fall. It's a 62" three blade CS prop with a large (13") spinner. They were able to create a custom lengths. Thanks for reporting on your status.

Sounds great, but I'd be afraid to ask what that cost. I ended up ordering an Ivo, and it should be here tomorrow. If it works at least as well as the Warp Drive, I'll be tempted to add the in-flight adjustable option. I'll try hard to resist though. I almost never fly cross country, so on the rare occasion that I do, I could easily adjust the prop for best cruise. The rest of the time it could stay on a good compromise setting for local flying.

Rusty

13brv3 wrote:Sounds great, but I'd be afraid to ask what that cost. I ended up ordering an Ivo, and it should be here tomorrow. If it works at least as well as the Warp Drive, I'll be tempted to add the in-flight adjustable option. I'll try hard to resist though. I almost never fly cross country, so on the rare occasion that I do, I could easily adjust the prop for best cruise. The rest of the time it could stay on a good compromise setting for local flying.

Rusty

Somewhere in the vicinity of $15,000 Au - probably the most expensive CS you can get for a Rotax 912

Need advice on how to remove the 912iS water pump elbow that interferes with the engine mount (so that I can replace that elbow with one with a different curve.) The elbows on my 912iS are threaded into the water pump housing and then either soldered or Locktite'd in (can't tell visually, but can see the threading.)

What is the best way to remove the elbow? Does it depend on whether solder or Loctite was used?

I have tried, without success, penetrant; and heating the housing next to the elbow - both with very high temp soldering iron, and with soldering/braising torch. I guess that the heat expansion coefficient of the elbow is much higher than the housing, so conclude that heat would only work to "destroy" the Loctite, or flow solder.

I understand that the elbows and the threading are fine and fragile enough that no substantial force should be used.

The engine mount in question is the Sonex 912 mount for legacy (not B) Sonex models (mine happens to be Xenos #32). Only one elbow is interfering. The hose could just barely clear, but with the engine running the elbow would risk destruction.

Ideas? Advice? Pointers to prior answers or other info I have missed?

Thank you

pschwenn wrote:Need advice on how to remove the 912iS water pump elbow that interferes with the engine mount (so that I can replace that elbow with one with a different curve.) The elbows on my 912iS are threaded into the water pump housing and then either soldered or Locktite'd in (can't tell visually, but can see the threading.)

What is the best way to remove the elbow? Does it depend on whether solder or Loctite was used?

I have tried, without success, penetrant; and heating the housing next to the elbow - both with very high temp soldering iron, and with soldering/braising torch. I guess that the heat expansion coefficient of the elbow is much higher than the housing, so conclude that heat would only work to "destroy" the Loctite, or flow solder.

I understand that the elbows and the threading are fine and fragile enough that no substantial force should be used.

The engine mount in question is the Sonex 912 mount for legacy (not B) Sonex models (mine happens to be Xenos #32). Only one elbow is interfering. The hose could just barely clear, but with the engine running the elbow would risk destruction.

Ideas? Advice? Pointers to prior answers or other info I have missed?

Thank you

It is installed with loctite 648 and needs a lot of heat to remove it. I had to re orientate all mine and one of them started to seap so I did it again and replaced the seaping one with a new elbow.

Try to direct the heat to the housing around the fitting and use a suitable dowel inside the elbow to rotate it with.

If you subscribe to Rotaxowner.com they have a video showing how it's done, otherwise there are a few utube videos out there I think under installing a rotax on a Zenith

Murray is spot on. I had to turn a couple as well for the ring mount. I just used a good heat gun, not any sort of torch. You just have to be patient and let it soften the locktite.
Rusty

So it’s been about a year since my complete cowling change.. I’ve since installed a new panel as well. I just wanted to post an update. (Better late than never)
I’ll be going to Oshkosh again this summer, starting out in Tucson Arizona. It’s about a 3,500 mile round trip for me and this’ll be the 3rd time making the journey with the plane! Very excited! I saw Jake got his swap completed. I’d love to hear how it does!
I hope the rest of you guys are doing well in your endeavors

Hi Harraripower,

Beautifully presented Sonex.

My Sonex will be returning to the workshop, next week, for a comprehensive rethink of the cooling system (oil temps way too high).

To assist my rethink, I am trying to get as much information as possible, from Rotax drivers, about their(successful) cooling management.

To this end I would ask that you post photos of your engine /cooling arrangements (both sides and front shot) and of your cowling In & Out air vents.

Oh! and your ground/taxi, climb out & cruise temperatures with OAT would also be helpful.

Thanks in anticipation

Hi Harraripower,

Would realy like to see some photos and get some dimensions (including your cowling belly scoop)