I took down my 3.0's Mercarb to investigate the fuel leak from the throttle shaft, and I'm not sure the shaft play is bad enough. I tested pumping the carb manually (while it had gas in it) and spraying a bit of WD40 on the closed butterfly; anything that drips on the butterfly eventually leaks out through the shaft....is the shaft's exit point missing something outside to prevent gas from leaking? I dont see a brass bushing, but I guess it can still be replaced?
To clarify, the leak happens after turning off the engine or when the boat is off but moving (i.e. being trailered). Fuel drips from the venturis and floods the engine (mainly affects hot starts, 15 min after turning it off). I think I know why it's flooding (the needle seat washer wasn't fully centered). Once I fix the flooding (replace the seat washer with the red fibre washer that came with the kit), all gas should stay in the bowl unless sucked by the engine. So it should not drip anymore. However, if fuel can go out, unmetered air can be suck in through the shaft.
I'm wondering if I'm chasing a ghost with the shaft play. thoughts?
To clarify, the leak happens after turning off the engine or when the boat is off but moving (i.e. being trailered). Fuel drips from the venturis and floods the engine (mainly affects hot starts, 15 min after turning it off). I think I know why it's flooding (the needle seat washer wasn't fully centered). Once I fix the flooding (replace the seat washer with the red fibre washer that came with the kit), all gas should stay in the bowl unless sucked by the engine. So it should not drip anymore. However, if fuel can go out, unmetered air can be suck in through the shaft.
I'm wondering if I'm chasing a ghost with the shaft play. thoughts?
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