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New LSA Engine

I'd sure be more comfortable with a Continental, over a Rotax. I'm even qualified to change my own oil in an O200. Wow! No gear box to overhaul every 600 hours, if it makes it that long. No dual carburetors to try to sync. No liquid coolant. No need to have the idle set at 1800 RPM, nor to crank the R's up over 5000 to get some horse power. Lot's of low end torque. Lot's less hoses and rubber stuff that deteriorates and Must be replaced every 5 years. And, a 2000 hour TBO to boot. And yes, it's a few bucks more. But, you get what you pay for.m Oh. did I mention that you can through all of the electrical stuff out, including the alternator and it will still start, and run, as long as you have gas, thanks to good old reliable mags.

It sure would be nice!!

Tom
 
Besides that, I'm sure that the RV-12 design is pretty well frozen at this time. A change to a different engine would be quite costly at this point.
 
Geico266 said:
At 200 pounds and $21,000 I can tell you what I think. The Rotax is $17K, and 120 pounds.
Click to expand...

I think you had better sharpen your pencil. Van said that the installed weight of the Rotax was closer to 180 lbs. not 120. Installed weight is what counts, not empty dry weight!
 
But, Mel is right. Changing horses at this time, in the 12, would be a major undertaking, no matter who does it. Oh well! It's nice to dream.

Tom
 
todehnal said:
I think you had better sharpen your pencil. Van said that the installed weight of the Rotax was closer to 180 lbs. not 120. Installed weight is what counts, not empty dry weight!
Click to expand...

160 lbs installed weight

So a switch to an LSA O-200 would be a 25% increase in weight

That would mean a major redesign for the RV-12
 
todehnal said:
No gear box to overhaul every 600 hours, if it makes it that long. No dual carburetors to try to sync. No liquid coolant. No need to have the idle set at 1800 RPM, nor to crank the R's up over 5000 to get some horse power. Lot's of low end torque. Lot's less hoses and rubber stuff that deteriorates and Must be replaced every 5 years. And, a 2000 hour TBO to boot. And yes, it's a few bucks more. But, you get what you pay for.m Oh. did I mention that you can through all of the electrical stuff out, including the alternator and it will still start, and run, as long as you have gas, thanks to good old reliable mags.

It sure would be nice!!

Tom
Click to expand...

Rotax requires a gear box inspection every 800 hr. not overhaul.

Carb synching is no big deal

I set idle at about 1600 - 1650 RPM that makes a prop RPM of about 775RPM at idle.

A 912 Rotax runs just fine without a battery or electrical system (if you had to shut down the electrical system) I admit it is a bit tough to start without one though.
 
todehnal said:
I'd sure be more comfortable with a Continental, over a Rotax. I'm even qualified to change my own oil in an O200. Wow! No gear box to overhaul every 600 hours, if it makes it that long. No dual carburetors to try to sync. No liquid coolant. No need to have the idle set at 1800 RPM, nor to crank the R's up over 5000 to get some horse power. Lot's of low end torque. Lot's less hoses and rubber stuff that deteriorates and Must be replaced every 5 years. And, a 2000 hour TBO to boot. And yes, it's a few bucks more. But, you get what you pay for.m Oh. did I mention that you can through all of the electrical stuff out, including the alternator and it will still start, and run, as long as you have gas, thanks to good old reliable mags.

It sure would be nice!!

Tom
Click to expand...
If you want the O-200 LSA engine, then I'd say go with it. It's a time proven engine and it's well understood.

The 912 isn't perfect - far from it - but it's not bad to live with and it well suited to the LSA definition. It's just different.

Some of my thoughts about the 912:

* Engine TBO is 1500 hr. Engines that run on mogas tend to make or exceed the TBO.
* Gearbox inspection interval is 600 or 800hr; overhaul is on condition. Again, engines that get fed mogas do better as lead from 100LL will accumulate in the gearbox.
* Oil changes are easy: Drain tank, replace plug, change filter, fill tank with oil, start and check for leaks and proper oil level. Very much like oil changes in a car.
* Liquid cooling makes it less sensitive to shock cooling and overheating on the ground at idle.
* Setting idle at 1800 RPM and syncing the carbs isn't hard - you rarely have to sync the carbs, most offten it's check and make sure they're balanced.
* Getting 5000 RPM is pretty easy - just open the throttle! The engine is quiet at WOT due to the standard muffler and low prop speeds (2200 RPM at engine redline).
* No mixture to adjust, which is helpful when taking off at high DA - no leaning to get peak Hp.
* Changing coolant lines at 5 years isn't difficult or expensive.

The 912 is a good engine - not perfect, but good. The TCM O-200 and Lyc O-233 are good engines that take well proven designs and make them better suited for LSA. I think they are viable alternatives to the 912S, but with the 1320lb MGTW limit on LSA, every pound counts, and the 912 is certainly lighter.

TODR
 
O200 Pricing??

Maybe I'm missunderstanding, but the way I read the article, the O200 would exceed $30K in price if there was no core to exchange. Here's an excerpt from the AOPA article.

".... Our intent here is to help folks that are building a kit or an experimental engine, and who have already purchased an engine, to upgrade to the Continental O200 Lightweight Engine without losing any money invested in their current engine. The core value for an O200A is $9,200. That amount would be added to the sales price for non-exchange purchase.?

Steve
 
stevemottin said:
Maybe I'm missunderstanding, but the way I read the article, the O200 would exceed $30K in price if there was no core to exchange. Here's an excerpt from the AOPA article.

".... Our intent here is to help folks that are building a kit or an experimental engine, and who have already purchased an engine, to upgrade to the Continental O200 Lightweight Engine without losing any money invested in their current engine. The core value for an O200A is $9,200. That amount would be added to the sales price for non-exchange purchase.?

Steve
Click to expand...

Not quite right Steve. I am pasting below the response from the factory on price and availability for your information. Notice that it clearly states, "No Exchange Core Required".

______________________________________
Hello Thomas.

Thank you for your inquiry.

I have attached the installation drawings for the TCM O-200-D (lightweight) engine. The dry weight is 199.7 lbs. The engine is designed for 3/8" mounting bolts.

We're going to introduce an O-200 lightweight engine for experimental aircraft in the very near future... Hopefully by the end of this month. This version will have a slightly different engine model designation and will be priced at $20,999, no exchange core required. (You might check our web site in a few weeks or so.) We expect to make our first delivery this September.

Sincerely,

James Towle
TCM Factory Service Centers
8600 County Road 32
Fairhope, AL 36532
251-436-8101 (Telephone)
[email protected]
 
Let's see, the O-233 will have the same weight, eight more HP, electronic ignition, throttle body fuel injection, and a 2400 TBO and wil be in the same price range.

Ummm, I think I would go with the Lycoming.
 
Actual complete weights

The 'installed' Rotax is lighter. Weights are often quoted with/without exhaust, etc, etc. The Rotax is lighter ( when its time to start the engine ).

John Bender
 
I took the time to weigh the Rotax and all its components ( exhaust system, oil tank, oil and coolant radiators, and plumbing ) before I installed it in my RANS S-7, and the all up weight came to 158 pounds. I did not include the prop in the weight. I would bet money that the "dry " weight of 200 pounds for the O-233 does not include the exhaust or any accessories. If we're going to compare installed weights, let's, at least be fair and not compare apples to oranges! That little Rotax in my S-7 is quiet, ultra smooth, starts easily, and runs like a Swiss watch. It's also easy to maintain and live with, day to day- burns absolutely NO oil- nor does it leak any. You'll love it, if you keep an open mind. Steve
 
IO-233 Weight

As quoted by Lycoming, their published weight includes all accessories, light weight starter, real alternator, etc. everything that you need for a running engine, with the exception of gas, oil, and exhaust.

I am so shocked by the various weights that are quoted for Rotax. I've heard everything from 120 lbs. to 180 lbs. That's a 60 lb. spread! Probably the one that I have the most confidence in is from Scott, which he states as 170lbs. I'm just not sure if that includes coolant, and a real alternator??

Tom
 
the_other_dougreeves said:
Some of my thoughts about the 912:

* Engine TBO is 1500 hr. Engines that run on mogas tend to make or exceed the TBO.
* Oil changes are easy: Drain tank, replace plug, change filter, fill tank with oil, start and check for leaks and proper oil level. Very much like oil changes in a car.
* Changing coolant lines at 5 years isn't difficult or expensive.
Click to expand...

Just a couple of things on these points:
- the TBO is slated to be raised to 2000 hours at some point in the near future. This will increase the value of the motor, or essentially make it less expensive. The price has gone back up to near $20K as of this month (for the 100 horse) but it'll still be a decent value with a 2000 hour TBO.
- Oil changes aren't that simple, actually. After refilling the oil tank, you do have to crank the engine over by hand or with the starter for a while until you get oil pressure to reprime the system and pump up the lifters. On mine, I pull my top plugs and spin the motor by hand with the prop until I get oil pressure. You can also apply power to the starter motor with the mags off to accomplish the same thing.
Severe damage to the valve train can occur if you skip this step.
- changing the coolant lines actually is electrifyingly expensive. Rotax wants you to use a particular type of 17mm Gates heater hose mostly because it meets this German DIN standard. The only source I've found for it is Rotax dealers, and they sell it for __$60 per meter__. That's right, _60$ a meter_ for some 17mm heater hose that should be 1/10th that cost. It takes about 2 meters to do the whole thing. Good thing the replacement interval is 5 years....

Other routine maintenance parts, like full carburettor kits are similarly shockingly expensive. A full overhaul on the carbs runs about 400 to 500 bucks if you have a dealer do it.

Lord help you if you have to ever replace any internal engine parts or anything in the gearbox. This will require going to the bank.... with a gun......

Fortunately, the 912 does stay together very well and catastrophies seem to be pretty rare.

I agree that the Connie is too heavy, way too freaking heavy. The props you'll have to use on it probably also are going to weigh a ton due to the strength needed for the direct drive. The 912 being a high-speed gear driven motor with small power pulses allows the use of lightweight props like the Warp Drive, Sensenitch, Powerfin etc.... I run a powerfin F model on mine and my plane (titan tornado) climbs like a homesick angel....

I wish it well tho, as Rotax desperately needs some good competitors....

LS
 
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todehnal said:
As quoted by Lycoming, their published weight includes all accessories, light weight starter, real alternator, etc. everything that you need for a running engine, with the exception of gas, oil, and exhaust.

I am so shocked by the various weights that are quoted for Rotax. I've heard everything from 120 lbs. to 180 lbs. That's a 60 lb. spread! Probably the one that I have the most confidence in is from Scott, which he states as 170lbs. I'm just not sure if that includes coolant, and a real alternator??

Tom
Click to expand...

I didn't see baffling listed...I realize it is not very heavy but it is additional weight. To be fare, the Rotax weight quoted below is with no external alternator.

I have always quoted approx. 160 lb installed weight for the 912 ULS (that's the weight I work from anyway) I may have told someone 170 at one time because the 160 (if I am remembering correctly) is minus oil and coolant.
 
rvbuilder2002 said:
I have always quoted approx. 160 lb installed weight for the 912 ULS (that's the weight I work from anyway) I may have told someone 170 at one time because the 160 (if I am remembering correctly) is minus oil and coolant.
Click to expand...

Thanks Scott. I think we have a pretty good understanding now of the weights that we are working with. Any way you cut it, the installation of an O-200 LSA, or an IO-233 engine, would probably add 40 lbs. to the front end of the 12. I'm not sure the structure integrity of the firewall and engine mount hard points would support that extra weight, not to mention the extra torque these engines produce, even though, a little lead in the tail would not be a big issue, if necessary.

Bottom line; Dwell on the plusses of the Rotax, at least until something better comes along.

Tom
 
todehnal said:
Thanks Scott. I think we have a pretty good understanding now of the weights that we are working with. Any way you cut it, the installation of an O-200 LSA, or an IO-233 engine, would probably add 40 lbs. to the front end of the 12. I'm not sure the structure integrity of the firewall and engine mount hard points would support that extra weight, not to mention the extra torque these engines produce, even though, a little lead in the tail would not be a big issue, if necessary.

Bottom line; Dwell on the plusses of the Rotax, at least until something better comes along.

Tom
Click to expand...

Another thing too on the connie vs the 912....
We _hope_ it's basically the same engine as the old o-200. If it's been revised substantially on the inside, it's not really a field-proven engine but a new engine with unknown bugs and problems etc. which will take a while to hammer out

The 912 has around 20 years of running out in the field now so it's a proven engine with known faults the few here and there that there are......

Personally, I think in the 80 to 100 horse range the 912 is still about the best you can do overall, especially for LSA. Again if the connie didn't still weigh a ton I think it'd be a better contender....

LS
 
lucien said:
- Oil changes aren't that simple, actually. After refilling the oil tank, you do have to crank the engine over by hand or with the starter for a while until you get oil pressure to reprime the system and pump up the lifters. On mine, I pull my top plugs and spin the motor by hand with the prop until I get oil pressure. You can also apply power to the starter motor with the mags off to accomplish the same thing.
Severe damage to the valve train can occur if you skip this step.
Click to expand...
Purging the oil lines is not required unless (1) you have opened up any oil lines or (2) you have rotated the engine backwards - it's optional with an oil change. However, it's fairly easy to do, engine rotates easily with the plugs out. You should be inspecting the plugs at every oil change, so it's easy to rotate the engine by hand with the top plugs out - just rotate the prop before you put the top plugs back in. You should open up the oil tank periodically to clean out the lead if you burn much 100LL. That requires a more thorough purging of the oil system (rotax-owner has a good video of the thorough purging procedure).

The biggest PITA is the location / orientation of the oil filter. It tends to leak oil everywhere while you're trying to get the new filter in. Worse, the leaked oil can get into the radiators (depending on the exact location of them in relation to the oil filter) and then slowly leaks out of the next few hours of flight, making a big mess. How do I know? ...

Anyway, make up an aluminum or cardboard "trough" to catch the oil while you're doing the filter change. I'll see if I have a photo of mine.

TODR
 
More interesting designs available!

I saw this engine on display a while ago, indeed a neat package. There is more alternatives, here in Europe.
For example:

Limbach: http://www.limflug.de/index.php?page=products&lang=de

Sauer: http://www.sauer-flugmotorenbau.de/Flugmotore.html

Hirth: http://www.hirth-engines.de/english/index.htm

JPX: http://www.jpx.fr/Jpx/english/pg_4tx90E.htm

If you search the Web you will find even more, but for the 12, Vans has choosen the Rotax and that is what it will be (LSA regulations!).

Regards, Tonny.
 
Hi Tony. I agree about all the engine options. But this is the first with a combination of old and new that really appeals to me. As soon as I get some property sold I'm starting a different "pop-rivet" 912 powered design. A Savannah VG from ICP in Itally (Skykits in the US). I would very much like to see the UL260i engine in that design as well.

-- Charlie
 
Low end torque?

I read several comments claiming a "low end" torque advantage for the continental engine.

Unless I am missing something, its horsepower (power) that makes all this work. Torque is an element of horsepower.

Even FP prop airplanes operate over a very narrow RPM range compared to an auto engine. Low end torque is a plus moving stoplight-to-stoplight, but in an airplane I don't see the advantage as long as the torque is reasonably flat over the operating range.

I just went to the rotax web site:
http://www.rotax-aircraft-engines.com/a_engine_912.htm

912 torque is flat to within +-3.5% between 3600 and 5800 RPM. That is the equivalent of (for example) being flat between 1676 RPM and 2700 RPM.

Static RPM on my airplane is 2200, so I just don't see the issue. There may be valid criticisms of the rotax, but I'd say this is not one of them.

By the way, my 300 HP Subaru WRX STi doesn't have much low end torque. Below 4000 RPM it relatively weak, and so its awkward coming off the line. Many cars have better "low end torque" and come off the line nicely. Some of their owners falsely think that translates into power. Sometimes I even torture them by staying side by side for a while so they will think its close. Then I punch it and wave goodbye.

There are faster cars out there, but that's because they have more horsepower, not because of more "low end torque"
 
N417AB/RV-8A said:
Van's just posted the price for their Rotax 912.........$24,000 and change.
Click to expand...

Just to keep things in context...the posted price is not for a Rotax engine...it is for the 6th sub kit (power plant) for building an RV-12.
It comes with much more than just a Rotax engine in a box, so the price amount can not be compared to advertised prices of just an engine (even though these would also need other parts purchased for completing the installation.
 
Mel said:
Besides that, I'm sure that the RV-12 design is pretty well frozen at this time. A change to a different engine would be quite costly at this point.
Click to expand...

It would.

I sat through Van's forum where Ken Kruger did most the talking and it was all about the design discussion that went on within the company when the 12 was on the drawing board. Sure they would have consider the new 0233 or 0200 but that was 4 years ago and neither company was interested in the LSA market at that time. Rotax was.

Rotax fit the plan, was available, and is still their engine of choice, all things considered, mostly weight. And like Van said, there's no way the 0233 or 0200 will cost less than the Rotax.

Beyond all that, I was most impressed with the design considerations that went into the 12. It is IMHO by far and away, the best airplane in this market.
 
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