Hello All,
Here's my story and a couple of questions related to technical solutions and "special" tool alternatives.
My F40 won't stay on plane for more than 15 seconds or so. Discovered float needle wasn't seating and suspect bowl was flooding. Confirmed by pinching off fuel line to top carb (is it #1 or #3?) while connected to a garden hose. Engine would idle great, for awhile, then run real rough. Pulling top plug wire had no effect. I pinched the top carb fuel line and after 30 seconds it ran great...then some seconds later it ran bad again; presumably the bowl ran dry. I released the fuel line and it immediately ran great for a short time and then ran bad again; I'm guessing it flooded again. At the times it ran good I pulled the top plug wire and there was a pronounced reduction in performance. No difference when it was running bad. I did all this repeatedly at idle and 4000 rpm.
I was shocked at the cost of parts. Particularly the o-rings. Yamaha wanted $12.00 EACH!!! Has anyone found an alternative?
I went on the cheap and bought a single float valve and replaced it. Now it runs great at all RPM's when connected to a hose. When I put it in the water, 2900 RPM tops!! I have read enough of the forum to know I have to correct the apparent fuel problem and will rebuild all 3 carbs. Any tips on how to do this without breaking the bank? Who sells kits the most reasonably?
I have purchased a manual and now have issues on special tools. Yamaha lists part numbers but won't sell me the tool! Example, I want vacuum gauge to sync carbs. No chance. Can I get any old vacuum gauge? Are to posts 5 or 6 mm...or something different.
Using a digital multimeter presents issues also. They say I need a high voltage adapter. Can I make one...does anyone else sell one?
Sure hope someone can point me in the correct direction.
Bob
Here's my story and a couple of questions related to technical solutions and "special" tool alternatives.
My F40 won't stay on plane for more than 15 seconds or so. Discovered float needle wasn't seating and suspect bowl was flooding. Confirmed by pinching off fuel line to top carb (is it #1 or #3?) while connected to a garden hose. Engine would idle great, for awhile, then run real rough. Pulling top plug wire had no effect. I pinched the top carb fuel line and after 30 seconds it ran great...then some seconds later it ran bad again; presumably the bowl ran dry. I released the fuel line and it immediately ran great for a short time and then ran bad again; I'm guessing it flooded again. At the times it ran good I pulled the top plug wire and there was a pronounced reduction in performance. No difference when it was running bad. I did all this repeatedly at idle and 4000 rpm.
I was shocked at the cost of parts. Particularly the o-rings. Yamaha wanted $12.00 EACH!!! Has anyone found an alternative?
I went on the cheap and bought a single float valve and replaced it. Now it runs great at all RPM's when connected to a hose. When I put it in the water, 2900 RPM tops!! I have read enough of the forum to know I have to correct the apparent fuel problem and will rebuild all 3 carbs. Any tips on how to do this without breaking the bank? Who sells kits the most reasonably?
I have purchased a manual and now have issues on special tools. Yamaha lists part numbers but won't sell me the tool! Example, I want vacuum gauge to sync carbs. No chance. Can I get any old vacuum gauge? Are to posts 5 or 6 mm...or something different.
Using a digital multimeter presents issues also. They say I need a high voltage adapter. Can I make one...does anyone else sell one?
Sure hope someone can point me in the correct direction.
Bob
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