Online Community of Zenith Builders and Flyers
Did anyone see the Motorav engine displayed at AirVenture? Really interesting: 100 hp, magnesium engine block, total weight 165 lbs (I do not know if that includes accessories/exhaust)! The engine is not quite in production yet, but they were advertising a suggested price of $12,900!
This engine is not being built by a fly-by-night company (pun intended!)! I did a little research and the parent company is RIMA which is a major magnesium alloy producer in Brazil that acquired VW's casting foundry. Motorav's primary design consultant was a former chief engineer at Continental. They did extensive analysis of their VW engine and designed a lightweight engine specifically for the aviation market. The engine has been in development for several years.
The external appearance of the engine was impressive:
However, the weight, coupled with the price, was even more impressive! This is a "dirt-simple" engine with a TBI carburetor. If that weight/price/performance holds, this will be a yet another realistic option for Zenith aircraft.
We can never have enough choices.
I'd be interested to know about fire safety. Magnesium is pretty flammable and burns really hot. You can get a fire starter kit from Harbor Freight that is basically a stick of magnesium and file to make shavings and a flint. Hopefully they are using a alloy that is lot less flammable than pure magnesium.
Great price/weight combination though.
Likely it is some alloy, but magnesium does burn fiercely once it gets going! I think, however, it would take a very hot and sustained fire to ignite an engine block vs shavings. The firestarters uses magnesium shavings - aluminum shavings will readily burn, too! The point being, if you had a fire of a magnitude to ignite the block, some very bad things have already happened to at least the firewall-forward and it would be the least of your worries ... if you are still around to worry! :>(
Magnesium blocks were used on the air-cooled Volkswagens from the 1950s until the end of production in 2003 (in Mexico) with no significant fire problems. They are also one of the most popular aircraft conversion engines. I think both the AeroVee and the Great Plains engines are magnesium block.
Many parts of commercial airplanes are magnesium including wheels and brake assemblies.
The risk of fire with a magnesium block engine is way way way down there on the list of things to worry about with an airplane engine.
Kinda looks like a combination of the 912 and a VW conversion.
I shall nick name it the "RotaxWagon". Or maybe a "VolksTax"
While I was walking thru the halls, I saw this engine. A quick glance and I thought to myself that it's just another VW conversion. Seeing your post, It now appears to me that it's more than that. The block is definitely different.
My main curiosity at this point is did they do anything for a better bearing at the prop end. The housing looks beefier there, but was just wondering if anyone has investigated this feature. I flew a VW conversion in my Sonex and was comfortable with it, but in my mind wished they'd beefed-up areas of concern.
ng at the website it looks like they did beef up the crank and bearing surface at tLooki
Always dangerous to "assume," but I assume critical details would be addressed as this is a purpose-built aviation engine and not an auto engine conversion. And after all, their design consultant was a chief engineer at Continental ... I think these people are serious! :>)