Rotax Engines

[skippydiesel]

FYI

Check out our flyrotax YouTube Channel

[nomadpete]

Here is Something related to Rotax engines that may affect all aspects of Rotax operation....

 

"

Bombardier's daunting debt load looms over company's plans

Bombardier is staring down some US$9 billion in debt maturing over the next decade, with that debt load looming large over all business decisions. For more on this, BNN Bloomberg spoke with Karl Moore, professor of business strategy at McGill University."

 

https://www.bnnbloomberg.ca/company-news/video/bombardier-s-daunting-debt-load-looms-over-company-s-plans~1894551

[Kenlsa]

Running your hands thru the wheat field? All that was missing was some reference to “saving humanity “ and the like.

Ken

[kasper]

2 hours ago, nomadpete said:

Here is Something related to Rotax engines that may affect all aspects of Rotax operation....

 

"

Bombardier's daunting debt load looms over company's plans

Bombardier is staring down some US$9 billion in debt maturing over the next decade, with that debt load looming large over all business decisions. For more on this, BNN Bloomberg spoke with Karl Moore, professor of business strategy at McGill University."

 

https://www.bnnbloomberg.ca/company-news/video/bombardier-s-daunting-debt-load-looms-over-company-s-plans~1894551

Can't seem to find the date of that video ... but as bombardier completed sale of their rail business recently and that video is talking about it still having a rail business I am guessing out of date info.

 

In addition the plane making division where airbus already has over 50% ownership will likely be snapped by them if/when debt becomes an actual problem ... plus of course the bits of bombardier we are interested in is a small sub limb on the recreational vehicle area ... not much to worry about in the next few years I suspect.

[onetrack]

Yep - a TV talking head discussing corporate future plans with a University boffin professor who has never worked outside the cocooned education system.

Neither would have any inside knowledge of Bombardiers future plans or financial projections. It's the equivalent of watching a video of the gossip around the coffee machine.

[nomadpete]

Sorry guys. Out of date article. I should have cross checked the source.

[Russ]

Query……can you SAFELY run a 912uls on avgas…

[RFguy]

yes

 

You need to overhaul the gearbox/ clutch more often  (see service letter)

 

Oil changes are recommended every 25 hours instead of 50 hours (see service letter)

 

You are likely to get CC buildup (since Bings generally run rich of peak ) 

 

There are additives like Decalin Runup that reduce/eliminate CC buildup. I use that on my Jab with LL100.

 

I don't know about about the gearbox though and whether there is an additive that can reduce that problem- - the combustion products of the lead end up in the oil and the gearbox accumulates it.

 

-glen

 

 

 

[skippydiesel]

1 hour ago, Russ said:

Query……can you SAFELY run a 912uls on avgas…

Of course! AvGas just needs a different(more intensive/expensive management strategy (as per RFguy above). 

 

I guess you could argue, lead being pumped into the atmosphere is a safety issue, for those who inhale it - but it wont bring the aircraft down.

 

I havent checked lately but I think the Rotax recommended oil change interval, when using UPL, is 100hrs - down t 25 hrs when using AvGas. Personally I always do mine at 50 hrs but that's by choice and is oil only, filters etc changed at 100 hrs.

[Russ]

Thanks guys….appreciated. It’s avgas periodically when mogas unavailable. Wasn’t sure avgas ok……again thanks

[Mewp]

I think i read up to 30% use of avgas is ok. Over that and what RFGuy says comes into play.

[skippydiesel]

49 minutes ago, Mewp said:

I think i read up to 30% use of avgas is ok. Over that and what RFGuy says comes into play.

Personally I would avoid AvGas  and only use it on those rare occasions, when away from home and ULP is unobtainable.

 

912's are designed to run on ULP - Using AvGas just increase your operating cost unnecessarily initial cost of fuel, followed by increased  oil changes and the build up of lead "scum" in the gear box, requiring (from bad memory) a 600 hr strip, inspection, clean.

[cscotthendry]

When in doubt, RTFM.

[skippydiesel]

3 hours ago, cscotthendry said:

When in doubt, RTFM.

True very true BUT remember this is the minimum standard for continued safe operation - a contentious operator/pilot can always chose to do a little better.

[F10]

The pain of this is of course, Mogas not available at most airfields. I’m most definitely not a left leaning greenie, but in this case, roll on unleaded AVGAS, yes!
Rotax manual, apart from lead sludge buildup in your oil tank and gearbox, the manual says it also erodes valve seats increases valve recession which is strange to me…I thought the whole purpose of lead was to lubricate valve seats and prevent seat wear?? I try to only top up with Avgas occasionally if I have to. So far, I’ve not had to. You get those fancy 20 litre bladders you can chuck in your baggage bay. Trouble is, you will need to cadge a lift to a Mogas garage, to fill it up, for re-fueling.

Edited October 2, 2021 by F10

[facthunter]

The Rotax runs too cold for the "usual"  beneficial effect TEL has on valve seats in aircooled motors for example which is what 100LL is made for. The lead was introduced in the late 20's to allow higher compression ratios to  be used  and produce more power without detonation destroying the engine.. . The valve seat life improvement was just  a happy side effect. TEL is detrimental to any BRONZE heads without hardened inserts and they will only do a short time before compression is lost. The lead alloys with the bronze and destroys  the contact surface. Nev

[F10]

The pain of this is of course, Mogas not available at most airfields. I’m most definitely not a left leaning greenie, but in this case, roll on unleaded AVGAS, yes!
Rotax manual, apart from lead sludge buildup in your oil tank and gearbox, the manual says it also erodes valve seats increases valve recession which is strange to me…I thought the whole purpose of lead was to lubricate valve seats and prevent seat wear?? I try to only top up with Avgas occasionally if I have to. So far, I’ve not had to. You get those fancy 20 litre bladders you can chuck in your baggage bay. Trouble is, you will need to cadge a lift to a Mogas garage, to fill it up.

[F10]

My understanding is, Tetra Ethyl Lead (TEL), back in the 70’s (in South Africa anyway), was in car fuel, things like MG’s and Austin’s, didn’t have hardened valve seats, as the valves were lubricated. Hardened seats came out in later car engines, when TEL was ditched, due to TEL pollution concerns. Yes, it’s primary function was anti “knock” or anti detonation. But newer car engines with hardened seats, could run happily on leaded, but running a “soft” valve seat car engine on unleaded, led to whaling and a gnashing of teeth!  Because Rotax are designed to run on no TEL Mogas, I still wonder why the valves have an issue. But, I will still comply and try to avoid AVGAS.

[facthunter]

It was used in race cars here at times with no detrimental effects as far as I can recall. The exhaust pipes ran a whitish colour inside due to a bromine additive used to clear the lead out. AS Bromine  (a haleide) is very chemically active it's no doubt dangerous and I'd venture to say is not used now. Hardened seats were used in Ford Mercury's pre war but not in the ordinary V8 (sidevalve/flathead) and they went for a long time. The tappets were not adjustable ands set at assembly by adjusting their length by grinding.  Nev

[RFguy]

wonder what rotax has to say about possible additives

 

I use Decalin Runup in my AVGAS (Jabiru engine) . (

 

One of the things in the decalin datasheet says "Prevents valve seat erosion from valve seat micro welding. It is equivalent to TCP (for experimental only)."

 

When I go to rotax, this will be a problem to figure out.

 

https://decalinchemicals.com/products/decalin-runup-fuel-additive/

 

 

 

 

 

 

 

[aro]

Rotax SI-912-016 has the answer:

https://legacy.rotaxowner.com/si_tb_info/serviceinfo/si-912-016-r12.pdf

[RFguy]

Good post ARO !

looks like Decalin and Alcor get the thumbs up from Rotax.

 

[jackc]

This is the suggested oil the  previous owner of my 582 powered Thruster was using……

 

 

Edited October 3, 2021 by jackc
spelling

[Thruster88]

I am sure Rotax recommend a mineral oil. I have always used Castrol tt later called 2t. Never had a ring stick in the last 37 years. synthetic is not recommended because it is hydroscopic?, it absorbs water and can cause corrosion, something ball and needle roller bearings can not tolerate. The 582 is not highly strung and synthetic is not required.  

[skippydiesel]

3 hours ago, RFguy said:

Good post ARO !

looks like Decalin and Alcor get the thumbs up from Rotax.

 

The way I read it Rotax were not actually endorsing either - just not apposing their use.