Well guys. This one I can’t explain but I’m sure there are much brighter minds here. During mag check, one side is fine. 100 rpm drop and slight raise in EGT. On the other side I’m dropping from 1700 to 1400 rpm and the EGT go through the roof. Weirdly, the even cylinders seem to rise immediately in comparison and they stay about 50 degree over the EGT of the odd cylinders. Does anyone have an idea? I don’t have the faintest. Any help would be greatly appreciated.

Out of time? Too much advance?

How many hours on those mags?

They’re just past their 500 hours. I have a set of overhauled ones ready to go. The mechanic I chatted with said it could be an induction leak.

Also, I did get a Blackstone report back a few days ago with high levels of chrome and silicone. It was suggested to check induction system because there might be particles getting in there that are causing abnormal ring wear.

I would agree with a mag issue. That would be a simple fix, try that first.
DENNY

Mags are out of time. How it happened, who knows but they are retarded too much. Late ignition firing and fuel air mixture is still burning as it goes out the tailpipe, that is why your EGT has increased.

Kurt

So what was the issue??
DENNY

All fixed! It was indeed the mags. I had the overhauled set installed and now I’m getting a clean 90-100 rpm mag drop and no big increases in egt. Still elevated egt but in normal ranges during mag check. All is good. Thank you for the help! This problem gave me a little scare at 8500’ takeoff and the engine was definitely not producing normal power for that DA. Lesson learned…. Pay more attention to mag checks, and don’t just assume that any drop means you’re good to takeoff.