semerson
Well-Known Member
- Joined
- Aug 5, 2017
- Messages
- 139
- Reaction score
- 31
Just had my O-540 overhauled for my 28-235. Installed everything and having issues with rough running at low RPM. Have a surefly on the left side and standard mag on right. All new plugs and wires. Actually had to replace the right wire harness cause the #1 lead was intermittent on testing.
Have had the mags timed by a shop and after some troubleshooting along with ensuring the carb is set correctly at the low end, have only been able to marginally improve the roughness but now can’t get the surefly to do any better than a 200rpm drop….
Initial inspection by shop found a loose p lead on the magneto and they believe the timing was off internally to the right mag…
Unsure what else to look for…. I’ve not been able to fly her in a year and a half with the engine overhaul and now the roughness….
I’ve sent the surefly in for bench testing just to make sure not an issue with it, but not very optimistic that anything will be found there…
Have had the mags timed by a shop and after some troubleshooting along with ensuring the carb is set correctly at the low end, have only been able to marginally improve the roughness but now can’t get the surefly to do any better than a 200rpm drop….
Initial inspection by shop found a loose p lead on the magneto and they believe the timing was off internally to the right mag…
Unsure what else to look for…. I’ve not been able to fly her in a year and a half with the engine overhaul and now the roughness….
I’ve sent the surefly in for bench testing just to make sure not an issue with it, but not very optimistic that anything will be found there…
