Budget for servicing

Need more info. ULS? iS?  How many total hours?  Flight hours expected?…

Budgets for costly hobbies??

Way too scary to think about 😈

I have run a 912 ULS for 13 years and have found the maintenance costs to be very minimal: Figure the costs of 3 litres of oil and one filter every 50 hours; occasional anti-freeze replacement; the 5-year rubber replacement; carb rebuild as needed (I do it on condition, not every 200 hrs); new fuel pump on condition (rarely); new spark plugs every 200 hrs (I use the cheaper NGK plugs); gearbox rebuild every 1000 hrs. Unless I have forgotten something (please chime in) my Rotax has not required anything else of any consequence. And yes, I always use genuine Rotax parts (except spark plugs).

Hi James,

Yes this is a Rotax Owners Forum, however the engine is usually connected to the airframe/avionics ie bit more involved in the maintenance cost, than just engine servicing.

You are a brave person for listing your engine service activities - bound to elicit comment;

Given that Rotax recomend 100 hr oil & oil filter change intervals, when using predominantly ULP, why are you doing 50hr intervals?  Are you using  AvGas?

Fuel pumps are part of the 5 year replacement ie not on condition. As this is a critical part of the fuel supply/engine running, I don't think "on condition" is the best advice.

Spark plugs have a 400 hr /ULP & 200 hr / AvGas service interval. As this is for Rotax supplied parts its probably reasonable to replace the NKG,s at 200 hrs.

The gearbox is "inspected" at 600hrs, if using Avgas and 1,000 hrs if  ULP. While inspection sounds low cost, it is likly some components will be replaced. 

There are a number of other "actions" on the service schedule, some at minimal cost (checking the overload clutch) others require either loan/hire equipment or personal investment eg "cylinder leak down " tester. 

"...always use genuine Rotax parts..."

Timothy Higgins is try to get an idea of maintenance cost.

To some extent this will depend on the regulatory conditions applied to the aircraft.

 In Australia, only factory built aircraft are required to use Rotax & factory supplied parts. Experimental / Homebuilt can go with the maintainers preferred parts.

Example; Significant reduction in the 5 year "rubber" replacement cost, can be achieved by sourcing hoses etc, from alternative suppliers. I would advise only using hoses that meet or exceed the Rotax specified product specification's.😈

Sean, My ongoing maintenance costs were related to the engine only since that is what the original question was; we all know there are other maintenance costs. Also, I did not include cost of tools/instruments since these are one-time costs.

I am using unleaded, non-alcohol mogas and I choose to do oil/filter changes at 50 hours. Even though 100 hrs is specified I believe you will find that the majority of folks on this forum choose to do 50 hours as cheap insurance.

You are correct in that a fuel pump replacement is specified at the 5-year interval. I couldn't remember when I wrote the above, but I checked and I did do the 5-year fuel pump change.

A 200 hour spark plug change is what Rotax specified for many years (with UL mogas) when they were factory installing NGK plugs, so that is what I still do.

My gearbox inspection/service interval is 1000 hours with UL mogas.

Again it is my choice to use genuine Rotax parts (except spark plugs); we all know you can save money by going 3rd party. The only time this hits me is once every 5 years-big deal, no hassle, just send in an order with a list of Rotax part numbers. You enjoy doing otherwise and that is your choice, just different than mine.

I am not recommending anything here, just sharing what and how I have been doing it for 13 years. The only things I have done outside this list is replace the Ducati voltage regulator once, and the old style copper radiator to the newer aluminum one, and the exhaust system once, but I don't consider these as ongoing maintenance items. Love my reliable Rotax 912 ULS.