Rotax versus Camit for a Onex

[gcm52]

I am considering engine choices for my Onex. One possibility is shoehorning a Camit 3300 into the Onex, which has already been successfully done by Merle R. Advantages to the Camit are that they appear to have corrected Jab problems, and it sounds like a real aircraft engine. Disadvantage is that it appears that the nose wheel strut has to be offset to make room for the carb. Is the Camit 3300 reliable? What has the experience been for those that bought one? The advantages of the Rotax (100hp) are that it is lighter, has established a pretty good record for reliability, might be easier to keep cool. Disadvantage for me is it sounds like a weed whacker and has less horsepower. Both cost about the same, both would probably be about as much work to custom fabricate the firewall forward. I would be interested in hearing real world experiences of Camit owners and Rotax 912 owners! Thanks.

[fastj22]

I've heard the Camit is coming in heavier than the Jabiru. That might make it just a bit too heavy to hang on the nose.
I also only know of one Camit flying so reliability is based on that.
I've seen pictures of a Jab2200 graphed on a Onex and the mount had to be pushed out so much it didn't look right. You might have the same issue with a Rotax 912. D-Motor might work well, but its super light too.
I think if I were to build a Onex, I'd be leaning towards the Aerovee Turbo.

[sonex892.]

I've heard the Camit is coming in heavier than the Jabiru. That might make it just a bit too heavy to hang on the nose.
I also only know of one Camit flying so reliability is based on that.
I've seen pictures of a Jab2200 graphed on a Onex and the mount had to be pushed out so much it didn't look right. You might have the same issue with a Rotax 912. D-Motor might work well, but its super light too.
I think if I were to build a Onex, I'd be leaning towards the Aerovee Turbo.

From the websites. Jabiru 3300 183.5lbs, Camit 182.4lbs, Aerovee 185lbs less oil. I'm guessing the turbo would take the aerovee weight up to 200 or more.
Steve
Sonex 892
VH-ZSX 3300 Jabiru

Merle Rs 3300 Onex looks very nice and quite normal.

[MichaelFarley56]

. Jabiru 3300 183.5lbs, Camit 182.4lbs, Aerovee 185lbs less oil. I'm guessing the turbo would take the aerovee weight up to 200 or more.

Just to clarify, that weight is for the turbo AeroVee. The non-turbo AeroVee is listed at 160 lbs.

[merle reppert]

Merle Reppert here
My JabEx ( Jab 3300 Powerd Onex ) Came in about 24 bounds heaver than my Aero Vee Onex --Engine mount is heaver-
Prop is heavier ---Holds more oil--Heavier oil cooler -----A real blast to fly ---

Merle Reppert

[gcm52]

Merle what prop did you end up using? Were you happy with the performance of the prop? How did the weight and balance end up with the Jab? It appears that the weight of the Jab is about the same as the Aerovee, but was the CG of the Jab in a different position than the Aerovee?

[LarryEWaiex121]

Larry in N. Idaho.
Just received my Camit 3300 and it appears to be approx. 14 lbs heavier than the Jabiru 3300 it replaced.
Mine is loaded with goodies because I took an in-stock engine as opposed to ordering one special. This one has the inhibitor system. the built in head heaters and sump heaters and finally, the 40 amp alternator. Regulator internal so old reg. comes off.
For me its pretty much a win win I hope? The heavier engine will improve overall CG with max load in seat. Low fuel conditions (under 7 gallons) shouldn't pose a lack of down trim as in the past.
My plan to get back part of the lost usefull load is to replace my Odessey PC625 with the new Extreme battery and that gets me back about 8-9 lbs.
So its weight forward where it helps and weight off the firewall to regain some load carrying ability. Sweet!
Did Camit address all of Jabiru's durability, servicablity and operational issues? I guess time will tell.
Lastly, I can't see a Rotax ever working well in the Sonex airframe. I have no beef with the quality or integrity of the product whatsoever. Rotax has their own quirks and Service Bulletin issues but have the biggest market share for good reason. My comments are based on the gear reduction aspect. The Rotax will turn a big prop slowly. Very efficient for an airplane that has about a 2-1 speed range. Cruises up to about twice the stall speed. My friends RANs S6 cruises about 100MPH.
Contrast that with the Sonex airframe that can easily reach 3-1 speed range and the lower speed, geared prop just won't cut it.
My Waiex with the previous Jabiru would cruise easily !48MPH and decend at about 2,700 rpm from cruising altitude at about 300-400 FPM descent at 160-163 mph in smooth air. If I had a Rotax running at 5,100 RPM in the same scenario, I'd be willing to bet it wouldn't go much over 120 mph straight and level and 130-135 downhill due to the prop holding the plane back.
If your flying a Rans type high wing or a Just Aircraft, or a KitFox, etc, I believe the Rotax is far superior for the above stated reasons. My guess is slow moving airplanes have real issues trying to cool a Jab? Just my guess.

[fastj22]

Doesn't the Camit also have heavier barrels? I can imagine the performance of one on a Onex though. Wow.

[LarryEWaiex121]

John,

Only know what I was told. Supposedly the barrels add about 8 lbs, and the alternator about 5.3 lbs more than the basic Jabiru generator. Inhibitor system and heaters I don't think, weigh maybe 2.5 lbs? Subtact out about a 1lb or 1.5 for the regulator and save another 9lbs or so on the battery swap.
I'm hoping that the all up weight diff. can be held to about 6-8 lbs. compared to the Jabiru.
If the new engine proves up to be all I'm hoping it will be, its a small penalty for me.
Someone has to walk out on the frozen lake and report back. LOL We shall see.

Larry
Waiex121YX

[fastj22]

I saw the Camit at OSH this year. Looks like a great option.