Do fuel pumps have to be replaced every 5 years?

Thanks, Rotax Wizard! Appreciate that info! Do you have a part number for the fuel pressure regulator assembly that needs to be replaced at 5 year rubber hose interval? Also, I noticed that page mentions the coolant and oil hoses, but doesn’t say anything about the fuel hoses? Don’t fuel hoses need to be replaced at 5y too? 

Yes rubber fuel hoses get replaced too.

Regarding time limits on hoses and rubber like bits.  Rotax can only call out what they install.  For the most part the rubber fuel lines are all from the OEM, not Rotax.  For many years now the only fuel system lines they supply are the orange coated teflon lines, they are on condition.  (not to be confused with fire sleeve over rubber hoses)  The 912 iS has no teflon or rubber hoses on the engine.  The only engine part is the pressure regulator at the top of cylinder 4.  The Rotax fuel pump assembly has rubber connector lines and they have to be replaced at 5 years.  The pumps do NOT require replacement until overhaul. 

All lines supplied by the OEM should have any continued airworthiness instructions in their respective maintenance manual, they are not in the original supply scope from Rotax.  

Cheers

Rotax Wizard wrote:

Hi All

Just a note, while they do not specifically call out pumps in the Line manual they do call out the pressure regulator on all the injected engines to have the internal regulator within the housing replaced at 5 years.  The reason for this is the diaphragm can become weak or even start to fail after that time.  There is only 1 regulator so it is felt that it is a more critical part and requires replacement based on time, not hours.  Regardless of hours it is to be changed as it is subject to deterioration due to fuel types and environment.

Cheers

Would the auto gas with alcohol or 100LL be worse? If it started failing we would get a decrease in fuel pressure as it would be leaking and not holding pressure? Could be a candidate for low fuel pressure?

Hi Paul

The regulator should be just fine at 5 years, it is a precautionary change in case the rubber diaphragm starts to wear or become porous.  Given it is working all the time it may be sensitive to fuel depending on what is in it.  Todays auto fuels have a lot of chemicals, aromatics,  and while I have personally never seen one of these fail it is possible.   Avgas, at least 100 LL, is pretty predictable and has shown to be stable with these types of materials.   To answer your question about leaking, I have not seen one do that as the pressure internal parts are within a small housing.   Can they start to change pressure, again the answer is perhaps.  There are many people who simply ignore this callout in the 100 hour.  More serious issues are with the lack of changing the small rubber lines on the dual fuel pumps, those indeed to deteriorate over time.  

Cheers