littlebill31
Smells of Raw Fuel
This is just a little test I did today and what I found.
My engine has been backfiring as of late on decelleration. Fresh rebuild on the carbs, everything else is fine. I figured I'd slowly go through, testing, and see what I could find WITHOUT jumping around.
One test at a time.
I got the bike started, warmed, and idling nicely. Then hit certain spots with some starter fluid. Now, I know only the left side was popping so I really only checked that specific side.
I went over everything and no increase in idle. Using a spray bottle is a little primative since it can cause false readings by dripping across an area or because of over-spray.
Then I had a little brain storm. I got an eye dropper and put 2-3 drops of starter fluid, (which I collected by spraying a heavy amount in a jug, then using the eye dropper to "suck" some up), right on top of the mix screw and no where else.
BINGO was his name-o!! (Kinda lucky to hit the right spot first though)
The bike's idle raced and the exhaust popped like a fire cracker.
I removed the mix screw O-ring and it was flattened badly. They are new O-rings, but sometimes things go bad. I probably didn't have it seated correctly to begin with, but that little ring made it seem as if there was a hole in my intake. The bike was popping loudly!!! This just shows what that little bugger, if bad, can cause.
To do another test with the eye dropper, to see if it worked good, I lossened one carb boot screw and did the same on the area where it had become detached from the intake. Same results.
So, I found that using an eye dropper can pinpoint the leak.
My engine has been backfiring as of late on decelleration. Fresh rebuild on the carbs, everything else is fine. I figured I'd slowly go through, testing, and see what I could find WITHOUT jumping around.
One test at a time.
I got the bike started, warmed, and idling nicely. Then hit certain spots with some starter fluid. Now, I know only the left side was popping so I really only checked that specific side.
I went over everything and no increase in idle. Using a spray bottle is a little primative since it can cause false readings by dripping across an area or because of over-spray.
Then I had a little brain storm. I got an eye dropper and put 2-3 drops of starter fluid, (which I collected by spraying a heavy amount in a jug, then using the eye dropper to "suck" some up), right on top of the mix screw and no where else.
BINGO was his name-o!! (Kinda lucky to hit the right spot first though)
The bike's idle raced and the exhaust popped like a fire cracker.
I removed the mix screw O-ring and it was flattened badly. They are new O-rings, but sometimes things go bad. I probably didn't have it seated correctly to begin with, but that little ring made it seem as if there was a hole in my intake. The bike was popping loudly!!! This just shows what that little bugger, if bad, can cause.
To do another test with the eye dropper, to see if it worked good, I lossened one carb boot screw and did the same on the area where it had become detached from the intake. Same results.
So, I found that using an eye dropper can pinpoint the leak.
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