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Discussion Starter #1
I rode to work yesterday morning in a pretty good downpour, which luckily cleared up by the time I went home. I was even able to head out for a nice ride before turning toward home.

The thing is, this morning when I needed to run an errand, I pulled out the Monster and headed out. While I was on the freeway, cruising was fine at 80-85mph. After getting off, the bike started to act kind weird, like one cylinder wasn't firing, then would kick in and run, then off again, kinda surging. If I give it a bunch of gas, then things run fine, but anything less then full throttle surges.

I filled up yesterday afternoon, and there's about 45 miles on that tank. I rebuilt the fuel pump about 6 months ago, and today picked up a new fuel filter, just in case. Still, she surges.

Pulled the plugs and the vertical cylinder was fouled uo. Cleaned the plug and re-installed. When I fired her up, she seemed to run, but I noticed gas leaking out of the collecter pipe.

I've checked all hoses and connectors and things look good. Someone at the shop suggested that there may be water in the fuel?
 

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Discussion Starter #2
Re: FCR help!

Update:

I pulled the headers off and WOW! Thats a ton of fuel in the vertical cylinder.

I've had it sitting for a bit, and gas is still flowing out steadily. I'm thinking that perhaps the carb that feeds the vertical cylinder is having a problem? What would cause it to keep delivering fuel?
 

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Re: FCR help!

Just guessing, as this has not happened to me, but...
Was there any water in the can or pipe being fed from that cylinder.. that may prevent that side from firing, and the fuel will keep flowing into there without igniting... kinda like the banana in the tailpipe scene from Beverly Hills Cop, but since you have two pipes, it would still run off of one cylinder. If there's just a borderlined amount, it may intermittantly fire...
 

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Re: FCR help!

I had the same thing happen on my FCR's about a year and a half ago. It actually filled up the cylinder and intake runner and was running out the top of the carb. I tapped the float bowl and it stopped trickling, pulled the plug, let the gas run out and cranked it over with the ign. off and plug out (lots of fuel everywhere), moved the bike, put it all back together, and haven't had the problem since. Kinda wierd, I guess the float just got stuck in the open position and tapping the bowl seated it.
 

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Re: FCR help!

Reckless Kelly is on target. I had same problem when putting stock carbs back on my SS when I sold it. Floats stuck in down position letting fuel flow.
 

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Discussion Starter #6
Re: FCR help!

Hmm, good ideas guys thatnks. I'll take a look at the floats tonight.

Thanks!

dj
 

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Re: FCR help!

Just the other day something VERY simiar happened to me. My bike was runnin' like poo below 3Krpm... seemed it wanted to flood. I got home and parked it overnight to come out and have the carb fill the vert cylinder... which after 24hrs leaked past the rings and filled my crankcase with gas. :mad: These carbs have less than 200 miles on them!! (as did the oil I had to drain! [smiley=veryangry.gif] ) I'm gonna take the bowl off and set the float levels just to make sure they're not fubar'd from the factory. Hopefully this'll fixit.
 

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Discussion Starter #8
Re: FCR help!

Well, I pulled the float bowl cover off of problem carb, and the floats are moving up and down easily. I turned the gas back on and fuels just flowing again. Any other ideas?

Looks like some of the fuel got past the rings too. Good thing I was planning on changing the oil this weekend anyways.
 

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Re: FCR help!

If the floats move up and down easily and they are moving the plunger correctly, then something is keeping it from making a good seal. Was there any debris in the plunger seat ? Are seals ok? Maybe try moving floats up with fuel on and see if fuel is leaking through.The fuel enters through that plunger seat and it has to be either the seat seal is not good or floats are sticking.
 

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Re: FCR help!

If my 2 cents help at all in this: y'all are barking up the correct tree looking at the floats. They do sometimes stick open and then the FCRs can flow some serious fuel. It's happened to me once. Bike starts running wierd at end of ride... shut it off and there's fuel pouring out! I turned off the fuel supply and then pulled float bowl of offending carb. Small piece of debris was cause. Looked like tiny piece of plastic bag.
 

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Discussion Starter #11
Re: FCR help!

Thanks guys. Your help is truly appreciated.

I pulled the carbs off to have a good look at the floats. Everything inside looked real clean. I used some compressed air to make extra sure.

Looking at the Sudco manual, it says to check for a clogged air vent (checked and seems good), and clogged needle vent. I can't find the needle vent on the diagram though.

After checking everything and blowing out eveything I could find, I re-installed them and turned on the fuel. Same problem. I'm going to pull them again and see if I can find that needle valve....
 

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Discussion Starter #12
Re: FCR help!

Ah ha! Thanks Chris. Checking now.
 

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Discussion Starter #13
Re: FCR help!

I pulled everything apart again and checked the needle valve. Clean as a whistle. Then, the best part. As I'm putting the float bowl covers back on I overtightened one of the screws!! Fark!



I tell ya, it's a good thing I don't own a gun, cause I'd probably shoot myself in the foot!!

Is there anything I can do with this? Will the other two screws be sufficient? Perhaps some JB Weld?
 

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Discussion Starter #14
Re: FCR help! (AKA: DJ screwed himself again..)

I put the float bowl covers back on without the one bolt and connected the fuel back up again to see if my messing with things cleared out any problems, but nope. Still flowing freely. I'm truly stumped, and just a weee bit frustrated.
 

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Discussion Starter #15
Re: FCR help! (AKA: DJ screwed himself again..)

Okay, pulled eeeveeeryything apart again. Blew out each and every port with air hose. Checked float height and function. Everything is good.

Still, after mounting them back on and turning on the fuel, I have a tone of gase flowing out. I have the plugs out and hte headers off, with the bike up on a rear stand. I can crank the engine with the rear tire and tons of fule blows out.

Any ideas? I'm gonna have another beer and stare at manual some more....
 

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Re: FCR help! (AKA: DJ screwed himself again..)

I have no in put whatsoever except that I'm having the same exact problem. I havn't gotten into it like yourself dj but hopefully you get it figured out.

I just replaced my fuel filter hoping that was the culprit and now I'm gonna use ring free to shock treat my gas and hopefully clear any debris in my carbs.
 

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Discussion Starter #17
Re: FCR help! (AKA: DJ screwed himself again..)

Update:

Still having the problem. At Chris' direction, I've done a bit more testing and it seems that the float is either not able to move up because of blockage or inability to float.

The float is empty (no sign of cracks or filling with fuel), and it appears to move freely in the bowl ( I can hear both flats clinking when turning th carb over.

I'm pulling them again and going to set the float in a cup of fuel to test for 'floatability' and checking the float height, just be sure it's set. Update to follow....
 

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Re: FCR help! (AKA: DJ screwed himself again..)

Good gawd man... you're making me nervous!! I pulled the culprit carb's bowl on my bike and didn't see a thing wrong. Float was at the right level... everything was clean as a bell. (as it should be, it has <200 miles on it!) :-/ I ran out of time last night and I haven't had a chance to turn the gas back on to see what happens. I hope I can get to it tomorrow night! Besta luck, Deej.
 

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Discussion Starter #19
Re: FCR help! (AKA: DJ screwed himself again..)

Okay, so tonight's findings....

Floats float perfectly. :)

I triple checked everything again and had a cup of coffee to think... I have two carbs, and one's not working. So. I pulled the float and float needle in each carb and swapped them. Problem still there.

Then I recieved some mail from Chris with a couple of suggestions, including "set up static test OFF THE BIKE". Doh!, why didn't I think of that? Ah well, next test is to swap the needle valves. I set up a footstool next the bike and prop the carbs up at the same angle they install at and hook up the fuel line.

Success! No fuel flows out of either carb. Put everything back together and start her up. Lots of fuel that was sitting in the cylinder pumps out, but before I get a chance to make sure things are truly cleared out, I start a fire. More on that later.... The misses also comes out to remind me that it's midnight and I'm running the bike without pipes... "And?"

I left the fuel on tonight and we'll see tomorrow morning if the problem comes back.

While I was cleaning up, a thought occurred to me. I _know_ that the carbs are functioning correctly right now, as the 45 minutes sitting on the stool without leaking proved. So, what might affect that one carb? Well, the fuel pump uses the vacuum off of that cylinder's intake port. Could the fuel pump be sucking fuel through the carb? Could some debris in the fuel pump cause this? Hmm... I rebuilt the pump a few months ago.

Anyhoot, hopefully there will be no fuel on the floor tomorrow morning and I'll never see this problem again. ;-)
 

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Discussion Starter #20
Re: FCR help! (AKA: DJ screwed himself again..)

Good gawd man... you're making me nervous!!
 
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