Hello Everyone,
I hope you all are staying safe. Fixing this bike keeps me sane. It's an old carburated Yamaha Thundercat. It sat for 4 years under a shed. I'm trying to get it running again. I'm hoping you guys may be able to help me get it running again.
It's got 19k miles on it.
Before the owner stopped riding it, the bike wouldn't idle. It would stall. The RPMs would dip. He gave up on it and let it sit for 4 years until I came along and told him we should fix it. Our first idea was to clean the carburator. We opened it up and found the jet's covered in green varnish. We cleaned both the pilot and main jet (soak in carburator cleaner fluid for a week). We even used a thin wire to go through the tiny holes. We attached everything, tried to fire it up, and it did! and then, died. And it then it kept failing to fire up. It'll fire like one cylinder while the starter keeps it running. It'll putter. We gave it starting fluid, and it runs on starter fluid just fine. We got it to rev to 7k rpms on starter fluid no problem. I was thinking maybe the fuel pump might be a suspect.
When flip the engine switch, I hear very subtle clicking, I am guessing the fuel pump. But the clicking gets slower and slower and then just stops completely. Is there a way to test the fuel pump for it working correctly? We didn't mess with the carburator diaphragms, NOR did we spend tons of time cleaning the inside passageways behind the jets (Have no idea how). What do you suggest we do next?
Any input is appreciated. Thank you.
I hope you all are staying safe. Fixing this bike keeps me sane. It's an old carburated Yamaha Thundercat. It sat for 4 years under a shed. I'm trying to get it running again. I'm hoping you guys may be able to help me get it running again.
It's got 19k miles on it.
Before the owner stopped riding it, the bike wouldn't idle. It would stall. The RPMs would dip. He gave up on it and let it sit for 4 years until I came along and told him we should fix it. Our first idea was to clean the carburator. We opened it up and found the jet's covered in green varnish. We cleaned both the pilot and main jet (soak in carburator cleaner fluid for a week). We even used a thin wire to go through the tiny holes. We attached everything, tried to fire it up, and it did! and then, died. And it then it kept failing to fire up. It'll fire like one cylinder while the starter keeps it running. It'll putter. We gave it starting fluid, and it runs on starter fluid just fine. We got it to rev to 7k rpms on starter fluid no problem. I was thinking maybe the fuel pump might be a suspect.
When flip the engine switch, I hear very subtle clicking, I am guessing the fuel pump. But the clicking gets slower and slower and then just stops completely. Is there a way to test the fuel pump for it working correctly? We didn't mess with the carburator diaphragms, NOR did we spend tons of time cleaning the inside passageways behind the jets (Have no idea how). What do you suggest we do next?
Any input is appreciated. Thank you.
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