Ha. Simply pop open the cap and let it run a bit. Obviously don't let gas splash out so lower level or mid. Runs good ? O.k. Now close the cap and go for a ride. Sputterings would be a clue.
Glass type fuses are still out there in a world of blade type now. Your choice. Glass American ratings are different than original Brit. ones. 17.5 vs. equivalent original Brit 35 A.
The psychiatrist is in. 5 Cents.