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Bike Cutting out

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gltee_9

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I recently replaced my diaphram pump (due to leaking) and bike seemed to ride fine. I ran it to empty then filled up. Next day my bike was a little hard to start, I just figured it was the cold weather. During my ride it ran rough and was "cutting" out on my and idled rough. Seemed to be fine the rest of the day. Rode all day yesterday with no problems, filled up with gas and today it is terrible. Won't idle, keeps cutting out or coughing on me, I have to have the choke pulled out just a bit to keep it running smooth but at a higher RPM. Just pulled the plugs and they look alright from what I can tell.....light tan to a grey color. Anyone have any idea what the problem could be? I'm thinking bad gas....but twice in 2 days from 2 different locations?? Any help would be greatly appreciated. Thanks.....also, how exactly is the diaphram pumps supposed to be installed? I do not have a manual...thanks
 
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You mention a choke so it must be a carbed bike and no mention of the year bike either (fill in your profile there). I would suspect something like sediment or water in the tank that got into the carb. You'll have to open it up and clean it out.
 
All my carb bikes were not Harleys so I don't know muc here.

Do you have a fuel filter that could be dirty? If you did run the tank dry, any sediment/water might be in the filter and can cause intermittent problems. I would probably drain the float bowl because water can collect there. I know the tank vent can cause all sorts of problems as well so you might open the cap when it is running bad to see if anything changes.

I don't know where the pickup is in the tank but if there is anything there it could cause intermittent problems.
 
gltee_9 said:
I recently replaced my diaphram pump (due to leaking) and bike seemed to ride fine. I ran it to empty then filled up. Next day my bike was a little hard to start, I just figured it was the cold weather. During my ride it ran rough and was "cutting" out on my and idled rough. Seemed to be fine the rest of the day. Rode all day yesterday with no problems, filled up with gas and today it is terrible. Won't idle, keeps cutting out or coughing on me, I have to have the choke pulled out just a bit to keep it running smooth but at a higher RPM. Just pulled the plugs and they look alright from what I can tell.....light tan to a grey color. Anyone have any idea what the problem could be? I'm thinking bad gas....but twice in 2 days from 2 different locations?? Any help would be greatly appreciated. Thanks.....also, how exactly is the diaphram pumps supposed to be installed? I do not have a manual...thanks
Click to expand...

'99 Dyna. Here is a pretty good schematic of the carb. You can see the accelerator pump well on this drawing.

CARBURETOR - 1999 Harley Davidson FXR2


I would do as Glider suggested above and drop the bowl on the carb. Clean out any crud in there. I would also drain the gas (take off the fuel line to the carb and put on a longer hose into a gas can) and then get your eyeball and a light in your tank to see what is in there. Then remove the tank valve and strainer and see if that is all globbed up with more crud. If the tank is full of stuff, take it off the bike and clean it out thoroughly. Clean everything well and reassemble. Add some Sea Foam or dry gas to the tank when you refill, and strain the gas from the gas can when you refill the tank (I like to use pantie hose "feet" to do this, but buy some just for this, do not take some out of her drawer - trust me on this!).

FUEL TANK - 1999 Harley Davidson FXR2


Note: these drawing are a '99 FXR2, but I assume yours is similar.

TQ
 
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I just read in the self help section about air getting in the throttle manifold causing problems with the carb. I did notice when I was re-installing my carb, that it seemed difficult seating it back on the manifold.......could this be the reason it is cutting out? I've also noticed it making more of a "popping" noise on a decel, good or bad? I had planned on tearing my carb apart and cleaning it tonight but if that's the fix will save much time and headache. It's on a 99 FXD. Thanks for all the replys....learing lots on this site!!
 
Unless the seal itself is compromised, it shouldn't be a problem. Any tears or holes in it would cause an intake leak.
 
Found out the problem which was in fact the seal. It wasn't seated properly on my intake. Runs fine now. Thanks for the help!
 
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