mid 90's 912UL

[pitfield]

I'm considering the purchase of one of two almost identical kit aircraft. Both kits and both 912UL engines are mid-90's vintage. The first kit was not completed until late 2008 and now has about 100 hours on the airframe and engine. The second kit was built considerably earlier and now has about 750 hours on the airframe and engine. Both engines appear to function equally well. And while both engines are well within the TBO hours as specified by Rotax, both are now beyond their mandatory 15-year overhaul date.

 

Questions:

 

1. Would the 15-year time limitation cause you concern given the relatively low times on the engines;

 

2. Would you be troubled by the unknown storage history of the very low time engine that has only been running for about 100 hours (but appears OK);

 

3. Am I an idiot for even considering purchasing aircraft with engines that are beyond TBO limitations?

 

Please be frank with your views. You guys have been hugely helpful and insightful in the past and I very much appreciate your assistance.

 

Best wishes,

 

Chip

 

 

[Guest Maj Millard]

Hi pitfield, I am assuming that they are both 80hp engines ?, but if not, no problem, as the 100 hp is not too much different. If the engines were 'pickled' prior to storage then great, you don't have any worries internally. If they weren't, the bores should be fine as they won't rust being 'Nikasil' (alum) There is a chance of there being some rust on the cam surfaces and other internal parts, but this would depend on conditions of storage.IE: wet /dry, oil in engine or without ?.

 

Of a bigger concern would be Rotax Service bullitens that have mandated certain reqirements. You need to get the serial Nos of both engines, and access service bulliten data applicable to the engines. The Rotax site is hard to navigate, but there are a couple of other sites that you can get the same info from, more up to date, and easier to access. You can download a complete list of applicable Service directives easily.

 

Of particular concern would be an ignition stator recall and mandatory replacement, that was required on some models. The factory paid part of it at the time, but only for so long, so you would have to pick up all the cost now ($2-3 Thousand). There were also valve collet upgrades, some cam problems, engine fuel pump replacements, and starter drive circlip upgrades. All these if applicable, would need to be carried out to assure a safe engine.

 

Rotax recommends all rubber be replaced every five years, this includes carb mount rubbers, carb diaphragms, all coolant hoses and oil lines, which you would also need to do. This includes fuel lines also of course.

 

You may get lucky and some of the SBs may not be applicable to you engines, per S/no, but you have to make sure. Other than that they are a great little engine that usually has no problem reaching or exceeding TBO. Good luck....................................................