I have one mag and one EI. I set the EI to produce 25* BTDC at 1800 to get consistent RPM drops on mag checks. I usually have about 10-20* difference from side to side. Today I was getting 40-50, so something has changed. I did some testing and noticed that when run at 1000 RPM on the mag alone, the #1 EGT rises quite a bit more, relative to the others. The other 3 cyl's move in relative unison. All 4 move together on just the EI.
I was thinking plug or wire. Rising EGT could indicate a change in timing, but not sure what would cause that on one cylinder. Plug looks good and #1 measures 950 ohms; within 100 of the other three. Plugs were just cleaned and gapped 10 hours ago. No lead deposits.
Any ideas or guidance on what is causing this? I will pull the mag and put in the spare as well. It has 300 hours, so I'll tear it down and IRAN.
Thanks,
Larry
I was thinking plug or wire. Rising EGT could indicate a change in timing, but not sure what would cause that on one cylinder. Plug looks good and #1 measures 950 ohms; within 100 of the other three. Plugs were just cleaned and gapped 10 hours ago. No lead deposits.
Any ideas or guidance on what is causing this? I will pull the mag and put in the spare as well. It has 300 hours, so I'll tear it down and IRAN.
Thanks,
Larry