I've been working on fixing issues with Carl my 1911 Touring. During a check over of the engine I discovered two piece valves still installed. So I decided to replace them. Car ran pretty good prior to change over, rebuilt coils, new wiring loom, good condition roller timer. Drove the car around town with no issues and was test driven by a experienced T guy who said it ran pretty good.
With that I replaced all eight valves, cut new seats, set valve lash to .010/.012", replaced cam gear also. Put the engine back together with no issues.
Replaced used roller timer with a new Anderson timer and have issues running on magneto. Car will start easily on battery but misses on magneto. When I run on battery it runs really good and easily cruises in the upper 30mphs. I've adjusted the timer to make sure all plugs are firing as they should. Still runs good on battery but not as good on magneto.
With the car running at 750rpm's on battery the magneto unloaded voltage is 14/15 volts AC. Using the 1156 bulb test it's bright. I can drive on magneto but it misses occasionally. When I accelerate on magneto it misses and I have to shift early, when accelerating on battery no misses and I can get a higher speed for shifting to high gear.
Car will start on magneto after it's warmed up.
Re-install roller timer, run engine, difference ??
Check coils for upper hardware physical measurements and test for electrical values
Has the coils been tested on a proper tester like a HCCT, Strobo Spark or ECCT?
Philip, relieve yourself of the burden and sell Carl to me!
Bill, gotta love your humor and tenacity! Philip, on my former '25 firetruck I had a similar issue. As Bob mentioned, I took my new Anderson off,( I didn't buy it, it came with another car) put the old (and maybe even original) roller timer back on and everything was fine. Just for the heck of it, I put the Anderson BACK ON, and same problem still existed. So back to the roller timer and now the Anderson sits in a drawer. Frankly, I don't like them. I'm still a TW guy.
Philip, Assuming you have checked what others have suggested, are you advancing the spark lever to find the optimum magneto voltage pulse to power the coils when operating on magneto? The car WILL run poorly operating on magneto with spark lever fully retarded, the engine will run fair with the spark lever advanced to the 2nd magneto pulse and run well when advanced to the 3rd magneto voltage pulse. You have to find the sweet spot when operating on magneto. That is because there are a fixed number of magneto voltage pulses (4 typically) available to power the coils and each magneto voltage pulse is associated with a specific crank shaft orientation which determines the spark timing relative to the piston position. Further advancing the spark lever to the 4th magneto may provide better performance at high engine speed but it will really hammer/knock when engine speed decreases so I don't recommend operating the spark lever at that near full advance position. Hope this helps.
Coils set per ECCT, I rebuilt the coils with new points and capacitors.
Next step is to go back to roller timer and see the difference.
Mike, yes I noticed that there is a sweet spot on the spark lever.
As stated in my post the car runs really good on battery just not so much on magneto.
Thanks for the tips
Today I performed the in-car magnet re-magnatization and things are better. Car will start on mag pretty easily but when I took Carl out for a test drive still had a miss when running on magneto. Checked again with the 1156 bulb and it's bright. Also checked with a analog VOM and now I'm getting over 20V AC across the bulb.
So I changed back to the roller timer I was using prior to the engine repair and now Carl runs fine. I did a quick six mile test drive and no issues on magneto.