Hello!

My name is Clay from Kansas.

I’ve been a Tiger owner since February, and I have been loving it! It was issue free for the first couple months, but now that it’s getting hotter, some issues are showing themselves, and I need some help troubleshooting them to get to a final solution.

Here is the list of mods, issues, and what has been done.

AIRCRAFT & MODS
1991 AG-5B 2900 Total Time
O-360-A4K
910 SMOH, 50 since top overhaul, Gibson Parts put in by Jet Air.
LASAR Magnetos (Electronic Ignition)
JPI 700(Primary CHT Probe not indicating, so only referencing this for temps)
Powerflow Exhaust

ISSUES
Running Hot – 85-95F day work hard to keep temps below 430 in climb, and 400 in cruise, specifically on #4, #3 is not too bad.
-Cruise 3K MSL around 2450, #4 400F CHT/1315-1330 EGT, 11 GPH, and 115-120 KIAS
-When I pull power back to 1850-2150, it runs rough, until I lean aggressively
-If I lean, it will run smooth at 1000 & 1800 on the ground, and 2300-2600 in flight.

WORK SINCE ISSUES (done by local Topeka A&P shop, Hetrick Aviation)
Oil Change
Improved existing Baffling (Large piece was needed on left), closed off holes with sealant, and did NLG boot mod to improve air flow out of engine.
Fixed broken lead on temperature probe that goes to LASAR control box

With that information: Everything was working well when I was able to lean during cold weather, but as it warmed up, I started to get to the point where I was running pulling power in climb and cruise, and going full rich in cruise. It was also running rough enough 1850-2150 to be a little uncomfortable. I researched and wondered if: I had an intake leak, bad mag timing, bad baffling, need a carburetor tune, had fowling plugs, or if the LASAR mags just had an issue.

I took it to a local shop to see if they could solve the issue easily. They did some baffling improvements, found a broken temperature lead going to the LASAR mags and fixed it, but were not able to time the LASAR mags, due to the special tool they need to be timed. (This is a little frustrating, because I brought it to this mechanic because he told me he could check timing on LASAR mags when I asked. He just assumed they were the same as all other mags, and later realized he needed special tools.)

I flew it this weekend for a few hours, and the temperatures seem to be better, but I still have to manage fuel, and I feel run it a little richer than ideal to keep temps down. This causes it to run barely rough at low and high RPM, but still noticeably rough 1850-2150.

I think the baffling could probably have work to make it ideal, but it seems fairly well done, so I suspect the Carb, or the LASAR mags.

So, I called Champion to try to find a mechanic who is familiar with the LASAR mags, and the technical support person (a guy with 23 years of LASAR experience) went a totally different direction, telling me the mags are no longer supported as of 2 months ago, and that if they are bad, then I should just switch them out.

That said, I don’t think I want to switch them out if they aren’t broken… they start great and they are supposed to have great benefits if they are working properly. I especially don’t want to switch them until the issue if fully trouble shot.

So, questions:
What do you all think is the issue?
Are there any mechanics familiar with LASAR? (Midwest near Topeka/KC preferred)
If its baffling, what are my closest Grumman experts, or at least majorly familiar mechanics?
If you do think I need to switch the mags? And if so, I think I would like to continue to use electric ignition, so do you all recommend Electroair or Surfly better?

Thank you!
-Clay