I mistakenly switched the petcock to prime after a long ride the other day. It sat for about 36 hours like that with the tank at a really low level, maybe one and a half gallons remaining. Upon discovery yesterday, I did not catch the petcock position right away. Fuel was dripping from the left side of the airbox, and under the bike was a little engine oil and a puddle of fuel. Initially I thought I got some bad fuel and a float stuck (the thought was confusing because of the vacuum operated petcock though) so I rolled it outside and cleaned everything up. I tried to start the engine as I planned to go fill up with good gas and add some seafoam in hopes of cleaning things out. The starter turned about a half crank and stopped. It sounded like an electrical short. I thought the starter may be submerged in gas or water so I pulled the cover, dry as a bone. Rolled back in and tested the battery, 12.5 volts, but swapped to another battery freshly charged and it cranked strong, but didn't fire up. I checked the ignition, plugs, good spark on all 4 cylinders. Must be a fuel or carb issue I thought. Still not sure why the oil on the ground but figured I would start with the carbs.
I have another set of carbs that a friend just dipped replaced o-rings bench synched etc for me so I swapped them out. I hooked up the carbtune, temp fuel bottle, fan etc, ready to sync and tune. Before starting I realized I moved the petcock to the vertical position prior to removing the tank, which if I had left alone in prime I would have made a mess and immediately realized what happened. So a closer look and the cause was discovered.
Now, I opened the oil fill cap and gave a sniff, it reaked of gas, but wasn't overly full. I drained and refilled with fresh oil. There couldn't have been that much gas in there as it measured just a hair under 4 qts. The oil was noticeably thinner though. If my body was in better shape after that last ride I would have hopped it up on the center stand for an oil level check, I'll never know now. It has no leaks, and no smoke from exhaust, and was running well, so I had no reason to think it was running low. Anyway....
Ready to sync and tune, even though the other carbs were not the issue, I came this far why not? These carbs have the stock 115 main jets and the others I was running had 110's so I am curious to see if there's a difference in performance, plus they're all shiny and nice looking as they are original to this bike!
Fuel flowing and fan running hit the button and varoooom. Wow kill switch, lower the idle. Try again, running now at a steady 1800 rpms. Pilot screws out 2 turns carbtune is flat. Blip the throttle, still flat and sounds odd. Cylinder number four is not cooperating, still cold. I pulled the boot and clipped about 1/4" of the wire and tried again. Not happening! Clean plug, good spark, hmmmmm.
I loosened the bolt on the bottom of number four and it has fuel in the bowl. Maybe the float height? I will go through and check all of the float height settings.
My other concern is that by trying to start with gas in the crank case I screwed something up in there. I will do a compression test too.
There was no issue with the battery. Hooked it up to a charger and it was still 98% charged, not sure what that was about!
Any critique, comments, advice is welcomed and appreciated.
Oh, the bike is all stock (exhaust, airbox, ignition)
Thank you
I have another set of carbs that a friend just dipped replaced o-rings bench synched etc for me so I swapped them out. I hooked up the carbtune, temp fuel bottle, fan etc, ready to sync and tune. Before starting I realized I moved the petcock to the vertical position prior to removing the tank, which if I had left alone in prime I would have made a mess and immediately realized what happened. So a closer look and the cause was discovered.
Now, I opened the oil fill cap and gave a sniff, it reaked of gas, but wasn't overly full. I drained and refilled with fresh oil. There couldn't have been that much gas in there as it measured just a hair under 4 qts. The oil was noticeably thinner though. If my body was in better shape after that last ride I would have hopped it up on the center stand for an oil level check, I'll never know now. It has no leaks, and no smoke from exhaust, and was running well, so I had no reason to think it was running low. Anyway....
Ready to sync and tune, even though the other carbs were not the issue, I came this far why not? These carbs have the stock 115 main jets and the others I was running had 110's so I am curious to see if there's a difference in performance, plus they're all shiny and nice looking as they are original to this bike!
Fuel flowing and fan running hit the button and varoooom. Wow kill switch, lower the idle. Try again, running now at a steady 1800 rpms. Pilot screws out 2 turns carbtune is flat. Blip the throttle, still flat and sounds odd. Cylinder number four is not cooperating, still cold. I pulled the boot and clipped about 1/4" of the wire and tried again. Not happening! Clean plug, good spark, hmmmmm.
I loosened the bolt on the bottom of number four and it has fuel in the bowl. Maybe the float height? I will go through and check all of the float height settings.
My other concern is that by trying to start with gas in the crank case I screwed something up in there. I will do a compression test too.
There was no issue with the battery. Hooked it up to a charger and it was still 98% charged, not sure what that was about!
Any critique, comments, advice is welcomed and appreciated.
Oh, the bike is all stock (exhaust, airbox, ignition)
Thank you
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