Boost pump on will rich cut. Fuel divider was done 2012 together with engine swap. Will cross-check.
This sounds like a broken fuel servo to me. I had that a few months ago. Worked fine in flight but the 4 GPH flow rate (way too rich) at 1000-1200rpm killed the engine, with tons of smoke coming out of the exhaust. It was opened up (in the USA) and they say they found no fault and no debris…
Mine worked quite well at 4gph once warmed up (i had it previously adjusted at that setting to cure the idle death symptom). And even a broken fuel servo shouldn’t change flow rates based on temperature with the TCM continuous injection – should it?
You never quite know…
Yesterday, departing from LFAT, very warm and engine still warm from the previous flight, I could not get any movement on the analog fuel flow gauge. Normally, one gets a tiny movement which indicates sufficient priming. But not always, regardless of temp!
The engine started up perfectly though, after the normal “5 seconds” of priming (cold start method).
My plan was to check the gauge during power checks (against the totaliser fuel flow) and if it still reads zero which could mean the fuel pipe to it has come off, and then obviously one won’t fly because there will be fuel p1ssing out somewhere.
The analog gauge is fed via a thin pipe from the extra point on the fuel distribution spider
The problem with a high idle (say 1000) is that you need lots more runway to stop.
Indeed 1000 rpm idle is not an option where I’m at.
@Michael – on the Columbia you also run the IO-550, no?
Yep and if I’m not full rich at roll out, with throttle closed, the engine sometimes will die, so I’ve gotten into the habit of landing full rich and putting a turn or two on the throttle once I’ve slowed down.
I almost never idle under 900 rpm, it’s just too lumpy .
I also look after 3 Mooney Ovations and have had this problem with their respective owners as well. If bumping up the idle doesn’t work then changing out the fuel divider diaphragm usually cures the problem.
I understand that you don’t want to land with the engine running fast, so just put a turn in the throttle once you’ve slowed down sufficiently.
Ballpark figure how many AMUs would that change cost? I always wanted to see Paris :)
What change is that ?
The diaphram ?
Yup.
