Mechanical fuel pump r&r?

[Browncbr1]

A while back I noticed unstable fuel pressure and missing at altitude.  I also found that pressure wouldn't hold at mixture cutoff on the ground.  I preemptively purchased a new fuel pump, but shortly later found that it was all due to a fitting at the fuel transducer that had small traces of dye. I tightened it and problem went away.  

My question is, what do folks think about removing and replacing my fuel pump at annual, even though the current one works ok?   Last time it was removed and overhauled, according to logs, was at 1998 major overhaul.   I am thinking I should keep this fuel pump on the shelf rather than risk a maintenance induced failure of fuel line fitting leaks or gasket leak or just infant mortality.    Thoughts???

[Raptor05121]

Nothing wrong, dont fix it. Wait until you need it.

[N6758N]

Keep it on the shelf, the Lycoming fuel pumps are nearly bullet proof. They are also a huge PITA to change out if the engine is on the airplane, if the plunger isn't installed correctly it can cause even more problems. 

[Andy95W]

2 hours ago, N6758N said:

Keep it on the shelf, the Lycoming fuel pumps are nearly bullet proof. They are also a huge PITA to change out if the engine is on the airplane, if the plunger isn't installed correctly it can cause even more problems. 

+1

[Browncbr1]

Thanks guys.  It's going to sit on my shelf for now.  

[Yetti]

The probably take an hour to change.  Not that hard even with the mags in place.   sacrificing a 5/16 allen wrench and cutting to the proper length then using a 1/4 drive socket to turn it was a great help.

If it passes the hold test, then there are probably other things that need upgrading like brake lines or oil lines or something before I would invite a maintenance unknown

 

[RobertGary1]

In my experience the mechanical pumps fail very slowly, developing less pressure. I have a new engine from Lycoming (2 years old now) and now my fuel pressure is always right at the top of the green.

 

-Robert