fwiw from an intelligent source... things to reverify ....
If it fired briefly right after the new amplifier was installed, then died and now won’t restart, the most likely causes are:
Most likely causes
1. Loose / bad electrical connection (very common)
After changing the amplifier:
- a wire may be loose
- bad ground
- corroded connector disturbed
Check:
- battery terminals (clean/tight)
- engine ground strap
- amplifier mounting screws / ground
- coil wires
- kill switch wire
A weak battery or poor cable can let it cough once, then fail because ignition needs adequate cranking voltage / speed.
2. Kill / stop circuit grounding ignition
Sometimes:
- key switch
- kill lanyard
- chafed wire
can short ignition to ground.
Quick test:
- disconnect the black/yellow stop wire (or kill wire) from the amplifier / ignition module
- crank again
If spark returns:
- kill circuit is the problem.
3. No spark at plugs
Before chasing fuel:
Do a spark test
- remove both plugs
- reconnect plug wires
- ground plug bodies to block
- crank
Look for:
Weak / none:
- amplifier wiring
- bad coil
- rotor / cap issue
- points / trigger problem
These systems need decent cranking speed to produce spark. Remove plugs during testing so the starter spins faster.
4. Rotor not seated / cap issue
Since you were in ignition:
- rotor may not be fully pushed on
- cap may be cracked / damp / carbon tracked
- center carbon button missing
Engine can fire once, then stop if spark leaks.
5. Fuel issue (less likely if it fired right after repair)
Check:
- primer bulb firm?
- fuel reaching carb?
- choke working?
If it fires on a tiny shot of premix into carb throat:
Best next step (in order)
- Charge battery fully
- Check all grounds and amplifier connections
- Test spark on both cylinders
- Temporarily isolate kill wire
- Inspect cap / rotor again
