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TrueAirSpeed
12-09-2010, 07:14 PM
The last three starts of my engine the Tachometer and Percent of Power indicators have been really slow to "come alive" (provide any indication). It usually takes about three to five minutes for each to show and indication. Once "alive" they readily come back on and stay on after an engine shutdown.
I'm fearful of that day when they don't.

Please advise.

Terry

TrueAirSpeed
12-10-2010, 04:57 PM
Once again today when I started the engine, the RPM and percent of power displays were slow to come on line---but did. Then after a one hour flight and shutdown both came on line immediately, BUT, at the mag check---There was zero indication on the left mag. Engine ran fine, EGTs remained constant but when I switched from BOTH to the LEFT MAG, the indicator went to zero.

Please advise.

Terry

Trevor Conroy
12-13-2010, 02:59 PM
Hi Terry,

What type of mags do you have (Pmag, Slick, Bendix, Lasar...etc)? Are you using an RPM board from us or the standard red or blue sensor screwed into the Slick or Bendix mag?

I think you might have an RPM sensor that is either failing or has a loose connection.

TrueAirSpeed
12-13-2010, 05:41 PM
Trevor, I have an Emag on the left side and a Pmag on the right side. It takes about three to five minutes for the RPM and Percent of Power to come alive on the initial engine start. And during successive engine starts the same day both come alive immediately. However, I have noticed that during the mag check (about 25% of the time) when I check the left mag, the RPM goes to zero. Right mag check normal. All RPM goes through the 4500 Deck engine monitor. I have nothing other than that.

Terry

Trevor Conroy
12-13-2010, 05:53 PM
Which pin are you routing the RPM output to and which mag are you using for RPM signal to the EFIS?

TrueAirSpeed
12-22-2010, 09:09 PM
It seems the problem I was having with delayed RPM and Manifold Pressure readings was a PMag problem and not an AFS problem. A quick turn around of the offending PMag with Brad at EMag ignitions with a ground run today shows everything back to normal ("knock on wood").

Thanks for your input,

Terry Small

Trevor Conroy
12-27-2010, 08:59 AM
Hi Terry. Glad to hear it!