lml@lancaironline.net Mailing List Archive

my IV-P will quit any time over 14,000 feet (at that altitude i always have the low fuel pump on) unless momentarily and for 3 seconds before switching tanks i turn the high fuel pump on, the short surge at 23,000 feet is scary when the engine quits and everything goes dead, the fuel mixture gets messed up and for a couple of seconds the engine gets very leannnnnnnnnnnnnnnnnnn

andres

Kevin Stallard <Kevin@arilabs.net> wrote:

Hi all,

Actually the question really is, why does the IO-550 require an electric fuel pump (besides priming/starting)?

Why is there both a low boost and high boost pump? Is this only for backup, or are there more sinister aspects of fuel delivery in the IO-550 at play here? In talking with a friend of mine, he mentions that the Lycoming io360 only has a low pressure fuel pump.

I remember a discussion about the TIO-550 and the fuel pump needs to be turned on above 10,000 feet. Why is this? This person I’ve been speaking to about this seemed to think it was to overcome vapor lock. Why doesn’t the IO-360 need something like this? Does the IO-550 need to be treated in the same way?

Thanks

Kevin