Status Update & A Few Issues

[kilr4d]

Hey Tom, couple thoughts:

Originally Posted by tomcomet

#1 - Gemini 1200 Engine Monitor & CHT - Currently CHT on #5 on the rear always shows hotter than the rest by 10-20 degrees and sometimes up to 450 on climb - very hot! Perhaps this is evidence of something more sinister or maybe the probe is off. #2 on the front reads a CHT of 1400 which is obviously wrong so there is something going on there.

#2 - Mixture - Front and rear mixture levers are REALLY different as far as positioning goes to get balanced fuel flow. The rear appears to work the way it should with good range and changes appearing on the FF Gages. The front lever is almost always full forward to give me 55 - 60lbs per hour fuel flow. That means for 55lbs per hour front is full forward and rear is half way back Seems strange. Not sure what is up there…

The maintenance manual for our engines is located in this post: http://www.337skymaster.com/messages...ead.php?t=3221

Page 9-4 gives some of the causes of high CHT's. You could also add incorrect spark plug heat range to that list.

That manual also addresses your fuel flows on page 12-13 and they should be over 100PPH/engine at takeoff for your elevation. Take off fuel flow should always be at the upper limit of the book numbers for a given altitude...it's soooo important for cooling. TCM has a specific differential pressure procedure for pump setup and it's pretty important. The shop you use is pretty big and it's the same test box for all Continental engines...they probably have it.

You can talk to your AMO about the lever postions but that's really just cosmetics. The flows themselves are more important than the rigging.

Originally Posted by tomcomet

#3 - Instrument Post Lighting - I can’t seem to get these to work at all. Rheostat? Which of the two light knobs turns on the little post lights?

I got both the dimmers and pulse lights from this company since they're STC'd for Cessna: http://www.maxpulsemaxdim.com/

[rrolland]

Tom:

Great advice by John K and Herb. Make sure that the fuel flows are set exactly right. My aircraft type is 140 pph. Looks like yours is 100 pph.

There is a good chance that your throttles will align better once the fuel rigging is right.


Richard

[tomcomet]

Yes, it is all great advice. I particularly like the link to the engine manual. Great reference!

The team at Brant Aero is looking at my fuel flows as well as the more aesthetic things like lever positioning. Today she got all new spark plugs and oil. Tomorrow...??? We shall see...