question Rotax 912 TBO

I will ask BF about this but also you, the Brain Trust - when does the Rotax TBO (10 year) calendar clock start ticking ?

• Date of manufacture ?
  
• Purchase Date "
  
• Installation/commissioning date ?
  

A supplementary question, if I may.

Your Rotax is, for argument’s sake, 1900 hours and 10 years old, (according to whatever the previous answer is).

Do you overhaul or bin it and get a new one??? I am told there’s not a lot of difference in price between the two options.

A supplementary question, if I may.

 

Your Rotax is, for argument’s sake, 1900 hours and 10 years old, (according to whatever the previous answer is).

 

Do you overhaul or bin it and get a new one??? I am told there’s not a lot of difference in price between the two options.

 

I dont want to stray to far from my question bu I may have something for you - Very many Rotax 900 engines run out of calendar time (10 years) with low engine (Hobb) hours - in most cases,subject to appropriate servicing and routine checks (cylinder leak down pressure checks etc) they will be able to continue operating. In your case calendar and engine hours have or will reach TBO (depending on serial number this can be 1200-2000 hrs) - your engines resale value has fallen to a very low amount BUT if it is still operating as you would wish, you can just continue "on condition" for as long as the engine will operate safely.

I have no personal experience of overhauling a Rotax 900 series but given the cost of original/Rotax parts & the specialised mechanical labour (also very costly) I think it would be a very close run in a cost effective sense ( between a recon and a new engine).

If you provide the labour and use at least some non Rotax parts, & do the job yourself it may be "cost effective" but without an official Rotax tick of approval, you would not have a valuable engine AND you would not be able to use it in a 24/certified air-frame you could possibly change to a 19). I think Kyle Comm might be /have gone down this path with an aftermarket Rotax rebuild/ upgrade (larger capacity) kit.

So in short - the choice is yours.

Thanks. Back to the original question.

Cheers.

BF have replied to my enquiry -

Seems that Rotax will allow a period of 2 years , between purchase of the engine & commissioning ie the TBO clock starts from whichever occurs first - 24 months from purchase or commissioning the aircraft/engine.

Seems I am out of date for the TBO calendar time - it is now 10 - 12 - 15 years depending on date of manufacture (engine serial number) and application of recommended upgrades, ( TBO engine hours , depending on SN, are still at max of 2000).

(See Service Bulletin SB - 912 - 057)

Lots of 'Maintenance release" aero stuff has a "shelf life". The 10 year thing with Rotax seems pretty "serious" as it's not really that long. The idea of zero timing anything that's been IN extensive service is pretty fanciful because aero engines and all parts of aeroplanes are built as light as is safely possible. If it's stored properly and not corroded "Unused" stuff should not deteriorate unless its rubber or some other short life material. Assemblies may require dismantling to properly assess their condition. Components that have done a lot of service even though they look OK, should realistically be lifed at some time or other depending on how they are operated. Overspeeding of engines can render them technically only a throw away . Some parts get re machined under a strict size limit and are not legal for aero work. ie decking crankcases.. Often the rebuild is NOT economically or from a safety viewpoint, the best choice. Nev

The TBO is 15 years or 2,000 hours whichever comes first, and it has been for about 10 years or more.

The TBO is 15 years or 2,000 hours whichever comes first, and it has been for about 10 years or more.

Depends on serial number/year of manufacture -See Service Bulletin SB - 912 - 057 .

My question (now answered) was when does calendar TBO start.