I replaced my fuel pump today and fixed the problem, which was declining fuel flow. It was a really interesting failure mode. It started flowing less and less over the course of an hour, going from 40 gph down to less than 15. If I would turn it off for a while (use the other pump), it would come back online strong as ever, but drop output a little faster.
I am glad that I had the fuel flow monitor, as I was able to catch it before I ever lost fuel pressure. (good for relations with the wife). Although it is not useful as a fuel totalizer, placing my flow scan on the fuel return line has turned out to be a useful tool It can give estimates of fuel usage, is great for fuel management reminders, and picked up this problem early and would be helpful in sorting out other fuel regulator vs. filter vs. engine vs. pump issues.
But what I really need is an EM2 to borrow. After sending back my my EC2 to Tracy for the relay fix and upgrades I just cannot get a good mixture map in place. I need to play with the mixture knob after every power setting change, including when taxiing around.
It is interesting, in general it idles better now than it ever did, but it just cannot tolerate throttle changes.
It also cannot tolerate idle at altitude.... It always had a problem at high elevation airports, as idle throttle puts the MAP off the lower end of the scale. But the new mixture map is especially bad. I was on short approach to Big Bear (6900 MSL) and pulled the throttle to idle and got the power I asked for, a non-turning prop as I crossed the numbers. Really good thing the wife was not on board!
So I'm begging here. Does anyone have an EM2 sitting around being unused? Tracy? I will make up a testing harness and give it to you in exchange for use of the EM2. You can then rent it out...
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