I am grounded at the moment due to letting my BFR expire, now I wait for an instructor to call by. Today I decided to run the engine to get a bit of oil circulated. Compressions were really good when I pulled it through.
I have had a bit of trouble with the tiny tach, which reads of an ignition lead. Just a few coils of wire around the lead and it induces a current which the tach reads and counts. Problem is the tach keeps re setting to one pulse per revolution instead of two. Not really a problem as I can tell if it is idling at 1000 rpm or 2000.
Today when I started up the tach was dead, no rpm at all, just a blank screen. Not a problem as I was not going flying, then suddenly it came alive, reading at twice the real revs.
I thought I would pose what happened as a problem for you. My first thought was that the tiny tach had failed completely, but as it came good, I thought an intermittent fault was probable.
I did a mag check and running on the left mag there was very little mag drop, running on the right mag there was some roughness and the tach went blank, but that is normal as the pickup is on the left mag HT wire.