Ram 750F weirdness
 

My Ram 750F has developed some problems that I wanted to run by you guys. I’m trying to decide whether or not to box up the thing and send it to Carlos........but thought I’d see if anyone here had any ideas worth trying before I do that.

I’ve recently had some flameout problems (5 runs in a row) when the throttle was pulled back to idle after running for less than a minute, but that seems to have magically cured itself. The last 3 runs I couldn’t get it to flame out but now the RPM undulates at most throttle settings. At full throttle the RPM along with the CP continuously drifts up and down, CP goes from 800 to 1300 as if someone was constantly running the throttle stick between 2/3rds and full. It never settles down and does this at idle too although not as bad. I’m thinking a tired fuel pump may be behind all this (flameouts included) but wanted a few opinions from all the experience that frequents this forum.

I’d appreciate any thoughts you may have,

John Fangohr

RE: Ram 750F weirdness
 

my guess it is yout fuel pump too
On my Autostart 750 the 1st pump locked up the replacement bought from Carlos was "tight" and it would not idle smooth +/-5,000 rpm until low RPM error-shutdown the turbine. The Pump Pulse Width was varing 50-55 and it should have been in the mid 70s. I am still waiting to get my pump back. Having to use a borrowed Jetcat pump!

befor sending it off to carlos...
check or replace fuel filters
inspect fuel lines for kinks or a pinch point.

can you get a pump from a friend to try ????

Bob

RE: Ram 750F weirdness
 

How about the fuel supply? Are you certain there are no bubbles getting through? An intermittent bubble supply could easily cause exactly what you describe.

RE: Ram 750F weirdness
 

Woketman and Bob,

Bubbles in the fuel were suspected early on, but we were watching the fuel lines very carefully for them and saw none. I'd like to try a new pump but there is only one other turbine owner in these parts (owns an AMT) and I doubt he has anything to try. I haven't checked the fuel filter yet (only 4 gallons through it so far) but I'll add it to my list.

John