blown up 912 ??

[DesertFox6]

Having the deepest respect and personal knowledge of GASSITT's uncanny abilities with Rotax 912 engines (an opinion shared by Lockwood who sends him parts to repair) I too am pondering his excellent original questions concerning climb angle and time versus oil pump output pressure.

As a rough estimate, the engine's oil pump pressure output, under wings-level, straight-ahead-vectored, positive G loading, should be adequate up to AT LEAST 45 degrees of pitch (.707 G at that angle) with no lube problem. This is also about the same point that the carbs would start to "unport" and falter; long before the oil pump output pressure would drop below that required to maintain adequate lubrication in the journals.

In this latter case, combustion would cease, and, in all likelihood, so would the engine along with the mechanical oil pump, but if the engine isn't turning, no oiling is necessary. I've not tested the airspeed required to rotate a flamed-out 912 up to the point the oil pump will rotate fast enough to deliver normal-range pressure, nor am I about to investigate this situation. Observing the severity with which a 912 stops at shutdown, I'm thinking I'd have to install a mach-meter to run such a test!

Assuming positive Gs are maintained, light aerobatic maneuvers have always been a no-sweat issue with a 912, so it's obvious to me that a whole lot more details concerning the conditions of flight at the time of the alleged "blow-up" are needed before any conclusions can be drawn. Something here is just too fishy for fact-finding.

Anyhooo, WELCOME ABOARD GASSITT! I often wondered why you hadn't joined us earlier; I'm awfully glad to see you in this forum and, after your initial experience with us today, I sincerely hope you aren't rethinking the wisdom of your decision!

I'm personally delighted that the Desert Fox Squadron's personal Engine Guru, "Doctor" (I like to call him that) GASSITT, is now on board...operators are standing by!!!

"E.T."
Desert Fox 6
(Opposing Solo)

[Dave Holl]

Well the way I read the post( just got a call from a customer that says he just bought a Rotax 912 engine from Lockwood and its blown up) the its suggests to me that it has just happened! if it said was I would have said that it had been bought in that condition. Maybe thats the difference between English and American!!!
With all that said it is an interesting subject and worthwhile discussion.
It is better if we all try and get on together and have a good debate on the issues after all thats what this forum is all about and not overeact would the responses have been the same if we were face to face?

[GASSITT@aol.com]

OK , iI got my fix this morning , BEAUTIFUL and smooth , eat your hearts out , Alright i changed the original post so ANYONE capable or piloting a Kitfox or anything without a training wheel on the front should have no problem (THIS TIME) understanding my post , My whole thought about this scenario was knowing the Rotax 912 as i do and it being a dry sump engine and the thought of residual oil in the system that it would take some doing to starve the engine ENOUGH to damage it , I was just looking for others input and thank you Michael for yours .

GASSITT

[Dave F]

Perhaps an overreaction, but what I read is the third party just bought a motor, it blew up and the vendor is blaming the third party (climbout too steep). Sounded more like a poke at the vendor than a search for information on the cause.

Steve, sorry if you're just trying to resolve the cause of the failure. I know that's what the forum members are all about.

post say from Gassit - ( credible FYI) that the engine wasa blown up turd to begin with ......... ahahah some just cannot read.

Prolly oil starvation..... from climb out ? doubt it.
high g's - doubt it
from operator errror -- I would be 98 % that is the problem....

[DesertFox6]

Dave Holl wrote;

..."Maybe that's the difference between English and American!!!" and I'd have to agree with him!


"The British and the Americans; two people separated by a common language." - George Bernard Shaw

Ever since spending some "guest time" at RAF Bentwaters many moons ago, I've never ceased to marvel at how a Brit can bring not only order to anarchy and sense to insensitivity but also a touch of class to what otherwise might be considered collectively uncoordinated, open season mud-wrestling: Thank you ever so much Mr. Holl!

And thanks too to all your countrymen who so marvelously hosted the rest of the world this past fortnight (including some of we colonial hold-outs!) as we no-doubt again attempted to track mud on your carpets, ingrates that we are!

And..."bob's yer uncle!"

"E.T."
(Good thing GASSITT got airborne early today, 'cuz it's just now noon here and it's already a hundred 'n' 'lebenteen Fahrenheit with more to come...! )

[N276KM]

I can understand the climb-out oil starvation if the setup is like what was intended for my Avid Mk 4. The oil reservoir was meant to go under the baggage compartment, and connect to the engine through long oil lines. In this situation, during a steep climb, particularly with cool oil that doesn't pump well, the oil pump could fail to keep adequate pressure at full throttle and a steep angle.

I never ran my engine with the oil reservoir in this location since I was concerned about oil starvation during startup, and following Rotax's mounting guidelines for sump elevation. My system is the Airedale engine mount location for the sump.

[szicree]

.... ahahah some just cannot read.

Prolly oil starvation.....

And still others spell like second graders.

[GASSITT@aol.com]

Proolly usin se**** grad enlish in concideration of the receipets ?

[Av8r3400]

Okay guys any more and this thread is gone.

[War Eagle]

Okay guys any more and this thread is gone.

Thank you Larry.