Ralf wrote:

 

I learned from an aircraft mechanic at our airport that many components in a certified airplane have a limited life time.

 

For examples hoses for hydraulics, brakes or fuel need to be replaced after ten years.

 

When I wanted to put the fuel pump back in the plane on my 4P rebuild project I found on the back of the pump the note that the pump needs to be replaced or serviced after ten years.

 

I had a pre buy inspection done at Lancair. At this time most of the components were already 12 years old. Lancair didn’t mention anything about expired components.

 

I am wondering if I should put all my old stuff back in the plane as long as it looks half way decent or if should replace certain things.

 

What components do I need to replace – the components of my 4P are approx 13 years old but the plane has just 240 hrs. I would describe the physical appearance of most of the components as old and messy.

 

 

Ralf,

Much of what we do with respect to aircraft servicing is “preventive maintenance.” Basically, historical experience, and in some cases, life cycle testing has allowed the manufacturer and the industry to set these “useful life” values. Most are a bit conservative IMHO, but some parts are sure to fail before their “lifetime” in any case. The bottom line is your comfort level…at least for an experimental aircraft. I used to “press” the battery age in my old Cherokee, but never the fuel pump. I also declined to replace the brake lines—since I almost never used them anyway except for turning more sharply… but the brakes are critical to safe operation of the Lancair IV-P, so they got a thorough going-over during the just completed condition inspection.

 

I’d say that if your parts are 13 years old, and have only 250 hours of use, those that have rubber or other synthetic seals in them are very good candidates for early failure. I’d replace (or overhaul) the fuel pump, brake master cylinders and brake cylinders, all gas springs (door and nose gear down). Consider overhauling the MLG, nose gear and flap actuators, and replacing the pressure sealing boots on the aileron and elevator tubes, plus the boots in the pressure compensator—if you have one. Not a lot of stuff, but it will give you some peace of mind? I’ve attached a list of “time change” items assembled by another builder. I apologize, but don’t know who sent it, so no attribution to source possible.

Good luck!

 

BOB