PA-32 engine runs rough without boost

[[email protected]]

I have a PA-32 that sometimes quits after starting when the boost pump is turned off. Two years ago the engine would quit when the boost was turned off so we replaced the mechanical pump. On a couple of occassions, I have had to leave the boost pump on for a couple of minutes after starting to keep the engine running and eventually the engine would run on just the mechanical pump.

Yesterday I did a short (10 mile) hop to pick up an instructor and after starting had to keep the boost pump on even during run-up or the engine ran rough and started missing.

Any ideas as to where to start looking for this?

 

[Markus Vogt]

 

[charlesmelot]

 

[PaulR]

 

[JoeB]

 

[JimC]

 

[bgmac]

 

[JimC]

 

[[email protected]]

 

[ikaros61]