Low Fuel Economy - Running rich, not sure why - Page 3

Water Warrior 2 · 09-16-2013, 02:56 PM

Just noticed in an earlier post. You said you spent a lot of time adjusting and readjusting the chain. Might be your problem with jerking right there. With worn sprockets and chain you will get a jerking sensation as the power is turned of and the chain repositions itself on the worn sprocket teeth.

ds1506 · 09-24-2013, 10:49 PM

Ok, so I just went through another tank since I adjusted the float, and it's still about 80-ish miles until reserve. So it would seem that the adjustment did nothing. Back to square one as as far as figuring out why I'm running rich I guess.

JohnC · 09-25-2013, 10:50 PM

These comments are made without going back and re-reading everything...

You said the PO left the petcock on "prime" and that caused trouble, presumably gas in the oil. This should not be a problem unless the float valve leaks. If it leaks then adjusting the float is a waste of time. How bad it leaks determines how much extra gas the bike gets. It could be very significant. Is the oil level increasing? Does the oil have gas in it?

Have you verified the air bleeds in the sides of the jets or jet holders are clear? They are vital to getting the correct mixture.

Lastly, remember Lucas' Law: 90% of all carburetor problems are electrical in nature and 90% of all ignition issues are carburetion.

ds1506 · 09-26-2013, 04:03 PM

When I changed the oil last originally, there was a very strong smell of gas, so I'm fairly sure that there was gas in the oil. However, since then, the oil level has not increased (in fact I seem to be leaking oil slowly, I'll address that issue once I get past the gas thing). I was under the impression, because of the gravity feed, being left on PRIme would over flow no matter what, even with a good float. Back when I was first messing with it and figuring out what did what, I set it to PRIme and I watched gas come out of the filter, so it would seem the float wasn't stopping it then either.

The jets are all clear, I'll check the holders again this weekend, but everything else seemed really clean. The float needle seemed fine as well, so I'm guessing that the problem lies with the float itself as far as that's concerned. Feel free to correct me if any of this is wrong. I was planning on doing a more intensive dive into the carb this weekend to try to see if I can find anything broken, but I'm not sure if I'm just overlooking the issue or not.

JohnC · 09-26-2013, 11:01 PM

When the valve is on "prime" it is simply open even though the engine is not running. the float valve should still stop the flow of fuel once the bowl reaches the correct level. If everything is working correctly, you could leave it on prime indefinitely and no gas would flow. (Not recommended, though, as things seldom work correctly forever...)

Watched gas come out of what filter?

ds1506 · 09-27-2013, 12:15 AM

Ok, so it sounds like the float should definitely be looked into.

Quote:

Watched gas come out of what filter?

The air filter. It's an aftermarket pod filter with no air box so I was able to watch the gas come out of the filter.

**jonathan180iq** · 09-27-2013, 09:09 AM

...That's a lot of gas...

JohnC · 09-28-2013, 10:59 PM

Quote:

Originally Posted by ds1506

Quote:

Watched gas come out of what filter?

The air filter. It's an aftermarket pod filter with no air box so I was able to watch the gas come out of the filter.

When the engine is running, all that gas is going into the combustion chamber. Definitely the float valve is not working. Something might be preventing it from closing, it could be assembled incorrectly, the needle or seat may be bad, or the float doesn't float.

Also, make sure the float bowl vent is working correctly. I'd expect fuel out of there, too.

ds1506 · 09-30-2013, 11:23 AM

Well I took the carb apart again this weekend and I'm fairly sure the float itself is ok. I'll check my assembly and the float valve again tonight. After this weekend it would seem that the seal for the float bowl is bad now. Whenever the bowl fills up, gas leaks out of the seam between the bowl and the carb. I'm wondering if the seal could've had a lesser leak prior to this week that wouldn't have noticed, as even with this one only a few drops every couple minutes are obvious.

ds1506 · 10-18-2013, 01:28 PM

Just an update: sealed the bowl up with some liquid gasket and messed with the float a little bit. Made it to 114 Miles before hitting reserve (used 2.7 gallons). Possibly could've made it to 120 before switching over, but either way it's an improvement. Not completely fixed, but considerably better than it was before.

The new thing that's been happening now though is when I shut of the engine it seems to have a small backfire(afterfire?).
Plug currently looks like this:

Doesn't look like it's running overly rich, but I'm not entirely sure what else I can really do to mess with the mixture at this point.

09-16-2013, 02:56 PM	#21
Water Warrior 2 Senior Member Join Date: Dec 2006 Location: Squamish B.C Canada Posts: 11,409	Re: Low Fuel Economy - Running rich, not sure why Just noticed in an earlier post. You said you spent a lot of time adjusting and readjusting the chain. Might be your problem with jerking right there. With worn sprockets and chain you will get a jerking sensation as the power is turned of and the chain repositions itself on the worn sprocket teeth. Login or Register to Remove Ads
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09-24-2013, 10:49 PM	#22
ds1506 Junior Member Join Date: Aug 2013 Location: Orlando, FL Posts: 14	Re: Low Fuel Economy - Running rich, not sure why Ok, so I just went through another tank since I adjusted the float, and it's still about 80-ish miles until reserve. So it would seem that the adjustment did nothing. Back to square one as as far as figuring out why I'm running rich I guess.
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09-25-2013, 10:50 PM	#23
JohnC Senior Member Join Date: Aug 2013 Location: New Hampshire Posts: 127	Re: Low Fuel Economy - Running rich, not sure why These comments are made without going back and re-reading everything... You said the PO left the petcock on "prime" and that caused trouble, presumably gas in the oil. This should not be a problem unless the float valve leaks. If it leaks then adjusting the float is a waste of time. How bad it leaks determines how much extra gas the bike gets. It could be very significant. Is the oil level increasing? Does the oil have gas in it? Have you verified the air bleeds in the sides of the jets or jet holders are clear? They are vital to getting the correct mixture. Lastly, remember Lucas' Law: 90% of all carburetor problems are electrical in nature and 90% of all ignition issues are carburetion. Login or Register to Remove Ads
	0

09-26-2013, 04:03 PM	#24
ds1506 Junior Member Join Date: Aug 2013 Location: Orlando, FL Posts: 14	Re: Low Fuel Economy - Running rich, not sure why When I changed the oil last originally, there was a very strong smell of gas, so I'm fairly sure that there was gas in the oil. However, since then, the oil level has not increased (in fact I seem to be leaking oil slowly, I'll address that issue once I get past the gas thing). I was under the impression, because of the gravity feed, being left on PRIme would over flow no matter what, even with a good float. Back when I was first messing with it and figuring out what did what, I set it to PRIme and I watched gas come out of the filter, so it would seem the float wasn't stopping it then either. The jets are all clear, I'll check the holders again this weekend, but everything else seemed really clean. The float needle seemed fine as well, so I'm guessing that the problem lies with the float itself as far as that's concerned. Feel free to correct me if any of this is wrong. I was planning on doing a more intensive dive into the carb this weekend to try to see if I can find anything broken, but I'm not sure if I'm just overlooking the issue or not.
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09-26-2013, 11:01 PM	#25
JohnC Senior Member Join Date: Aug 2013 Location: New Hampshire Posts: 127	Re: Low Fuel Economy - Running rich, not sure why When the valve is on "prime" it is simply open even though the engine is not running. the float valve should still stop the flow of fuel once the bowl reaches the correct level. If everything is working correctly, you could leave it on prime indefinitely and no gas would flow. (Not recommended, though, as things seldom work correctly forever...) Watched gas come out of what filter? Login or Register to Remove Ads
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09-27-2013, 09:09 AM	#27
jonathan180iq Super Moderator Join Date: Jan 2007 Location: Dalton, GA Posts: 3,996	Re: Low Fuel Economy - Running rich, not sure why ...That's a lot of gas...
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09-30-2013, 11:23 AM	#29
ds1506 Junior Member Join Date: Aug 2013 Location: Orlando, FL Posts: 14	Re: Low Fuel Economy - Running rich, not sure why Well I took the carb apart again this weekend and I'm fairly sure the float itself is ok. I'll check my assembly and the float valve again tonight. After this weekend it would seem that the seal for the float bowl is bad now. Whenever the bowl fills up, gas leaks out of the seam between the bowl and the carb. I'm wondering if the seal could've had a lesser leak prior to this week that wouldn't have noticed, as even with this one only a few drops every couple minutes are obvious.
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10-18-2013, 01:28 PM	#30
ds1506 Junior Member Join Date: Aug 2013 Location: Orlando, FL Posts: 14	Re: Low Fuel Economy - Running rich, not sure why Just an update: sealed the bowl up with some liquid gasket and messed with the float a little bit. Made it to 114 Miles before hitting reserve (used 2.7 gallons). Possibly could've made it to 120 before switching over, but either way it's an improvement. Not completely fixed, but considerably better than it was before. The new thing that's been happening now though is when I shut of the engine it seems to have a small backfire(afterfire?). Plug currently looks like this: Doesn't look like it's running overly rich, but I'm not entirely sure what else I can really do to mess with the mixture at this point.
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