My '65 CA77's been fouling plugs for some time. After making several attempts at adjusting air/idle settings I finally took off the carb to check things out. Completely cleaned everything and reassembled, keeping the original jets. Afterward still had carbon-coated plugs after only riding 5-10 miles.
Since I was also curious about gas mileage I did a test ride a few days ago. Put in 1 gal gas (above the reserve) and planned to ride until it needed to be switched to reserve, therby getting mpg. Twice during the ride I had to stop, remove plugs for cleaning, then once things were cooled I put 'em back in and continued riding. I ended up getting 50 mpg by the way, but here's my question:
The second time I cleaned them they were only lightly coated with carbon, instead of completely black like before. When I returned home & checked them again they were a nice golden tan color - no carbon at all !!!
Since I hadn't tinkered with the carb settings at all during this ride, I have a theory. I thing a long steady ride this this was "therapeutic" in some way. Could it be that I got the engine hot enough that maybe it burned alot of carbon buildup that was inside?
Whatever happened I'm not sure, but this I know. I still have the carb settings about the same as they were and when I check my plugs now they look to be a nice healthy color, and no more fouling.
Will ride again tommorrow (depending on rain forcast) and continue checking vital signs on this old girl.
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fouling plugs ... does this make sense?
Usually when plugs foul that quickly, the fuel level in the bowl is too high. Sometimes crud in the petcock fouls the needle and seat, and no matter how clean you get the carb, it just fouls again. If it's all clean, you could try setting the float up a few mm more. There's a lot of posts here about float height and exactly how to set it, but in the end it's not really the float height that's important it's the fuel level. You may have flushed out your problem however during the last ride!
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fouling plugs ... does this make sense?
Yeh forgot to add that I put a fuel filter between the fuel cock & carb, and have checked the screen in the fuel cock several times. Usually get a little more crud out each time, filter still looks ok. But judging by the color of the plugs I'm making progress.
Fouled plugs
Hi Rider5,
What is your elevation? I moved from sea level to 5,000 ft elevation, and had to re-jet my Superhawk pretty radically. It fouled the plugs so bad I could barely get it running. I reduced both the slow and high jets, and now it runs like a charm. You might want to just lower your needle in the carb to see if it makes a difference.
If you have garbage in your tank that gets through to the carbs, that will keep your float sticking open, and will obviously cause a rich condition. I had a small hole in the screen filter in the petcock, and it let junk through. Now that it is fixed, nothing seems to get through to the carbs - it's a good system.
Just some thoughts! Hope you get it fixed. My Superhawk on the highway gets about 55 mpg.
GG
What is your elevation? I moved from sea level to 5,000 ft elevation, and had to re-jet my Superhawk pretty radically. It fouled the plugs so bad I could barely get it running. I reduced both the slow and high jets, and now it runs like a charm. You might want to just lower your needle in the carb to see if it makes a difference.
If you have garbage in your tank that gets through to the carbs, that will keep your float sticking open, and will obviously cause a rich condition. I had a small hole in the screen filter in the petcock, and it let junk through. Now that it is fixed, nothing seems to get through to the carbs - it's a good system.
Just some thoughts! Hope you get it fixed. My Superhawk on the highway gets about 55 mpg.
GG
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