Harley Davidson Forums banner

1 - 20 of 22 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?
 

·
V-Twin Junkie
Joined
·
662 Posts
Was it sitting? If so, get that carb off and apart and clean it fully -hot tank the body, soak everything, wire and blow out every passage, and replace all o-rings and gaskets.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #5
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?
Was it sitting? If so, get that carb off and apart and clean it fully -hot tank the body, soak everything, wire and blow out every passage, and replace all o-rings and gaskets.
did clean out the carburetor, and passages.
O ring and gasket looked good.
 

·
Registered
Joined
·
1,651 Posts
did clean out the carburetor, and passages.
O ring and gasket looked good.
Is this a new to you bike? If not, the jetting in the carb could be AFU for your altitude and or any intake / exhaust changes that have been made (with or without your knowledge).. meaning: Prior owner.

I brought a 03 sporty back to life that had been stored for over 15 years. Had a hell-of-a-time getting the carb to come in. I got it to run (sorta), well enough to take to a shop hand had them tune it.. That bike always seemed to run better with the enricher (choke) on.

Check for vacuum leaks around the carb / intake: from the opposite side of the bike from the carb: spray carefully with short spritz of WD-40 (Being careful to PREVENT the spray from getting into the intake side of the carb, as this causes a false indication). If the rpms increase with the wd, that indicates a air leak.

Another point: You stated that "as soon as it gets warm it looses power and stops".
This is a sign of a stuck float. If the float is sticking, it will prevent or, mostly prevent (leakage) any fuel from getting through the fuel line into the bowl. It could be just seeping in, just enough to provide enough fuel to get the engine warm. But not enough to keep it running.. Check the float as specifically detailed in the Harley Shop Manual. It's a tricky one to explain and it is explained very well in the H.D. Shop manual for that model. Been there!
 

·
Registered
Joined
·
1,651 Posts
One more to look at: The Pet-cock on that bike is vacuum activated. Make sure the small vacuum line from the intake is attached to the smaller fitting on the pet-cock and inspect that line for cracks! It no workie- carb no workie, either!

This was yet another i learned the hard way!
 

·
Registered
Joined
·
4 Posts
Discussion Starter #8
One more to look at: The Pet-cock on that bike is vacuum activated. Make sure the small vacuum line from the intake is attached to the smaller fitting on the pet-cock and inspect that line for cracks! It no workie- carb no workie, either!

This was yet another i learned the hard way!
I replaced the vacuum line already, there are no hose clamps on it. They could still leak of course.
This is my bike since new, no mods.
I activated the float and checked for flow no flow, all looks normal. move real easy.
It all started suddenly, all was good bike suddenly backfired and turns off. Had to leave it overnight, then stared again, got warm stopped again.

Today I cleaned fuel filter, all lines, carburetor, and there is actually no change.
Starts runs for a couple of minutes, with choke on then suddenly stops.
Absolutely no change to before cleaning ...
Which is really weird, if rootcause would be carburetor, I would have expected at least some change.....
 

·
Registered
Joined
·
24,257 Posts
Did you remove the petcock and clean the fuel strainer inside the tank?
If it is clogged , the fuel flow will be reduced.
Look inside the gas tank for peeling or bubbled paint.
 

·
Registered
Joined
·
1,143 Posts
I had a similar issue with a Honda Rebel years ago . . . thought it was a fuel issue and turns out it was electrical (I think it was a control module or something like that). When the part heated up, it shorted out, the bike quit (sometimes backfired). A few minutes later, I could start it up and then the same thing happened. Carburetor was clean, adjusted correctly, new gasket set, fresh gas, clean tank, filter, etc.
 
  • Like
Reactions: GotGold and 1/2 Ton

·
Registered
Joined
·
1,651 Posts
Have you performed the wd-40 test yet?
 

·
Registered
Joined
·
1,651 Posts
I had a similar issue with a Honda Rebel years ago . . . thought it was a fuel issue and turns out it was electrical (I think it was a control module or something like that). When the part heated up, it shorted out, the bike quit (sometimes backfired). A few minutes later, I could start it up and then the same thing happened. Carburetor was clean, adjusted correctly, new gasket set, fresh gas, clean tank, filter, etc.
Had that issue with a Ossa 250. It turned out to be the "Motoplat"....Italian for Coil? Anyway , it was the coil. This can be caused by either a cracked coil, or simply a bad or dirty ground from the coil. (Mine was cracked).
 

·
Retired citizen
Joined
·
24,100 Posts
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?
Replace the pilot jet with a #46.
 
  • Like
Reactions: Fuzzman71

·
Registered
Mr. James
Joined
·
917 Posts
Immediately after it dies check to see if you have spark at the plug wire. It the ignition module is bad, like has been suggested as a possibility already, you will find out right quick.
 

·
Registered
Joined
·
1 Posts
Jesus, dude. It's a 2003 and it has 4000 miles on it. Best recipe for keeping it running? Ride the damned thing.
Jesus, dude. It's a 2003 and it has 4000 miles on it. Best recipe for keeping it running? Ride the damned thing.
I bought my '03 with 236 original miles on it. I had the same problem. Rebuilt carb with a stage one kit... runs like a top, 12k later!
 

·
V-Twin Junkie
Joined
·
662 Posts
I bought my '03 with 236 original miles on it. I had the same problem. Rebuilt carb with a stage one kit... runs like a top, 12k later!
Not saying there isn't an issue. Am saying that that bike sits more than it runs, and that is bad for machines.
 

·
Registered
Joined
·
4 Posts
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?
Maybe running out gas? rhe fuel
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?

Sure sounds like a stuck / partially sticking float. Run it till it warms then tap the side of the carb bowl. Don't be too soft or too hard. If the float is stuck with a full bowl once gas runs out it obviously will sputter out and may backfire. It could be letting a trickle into the bowl while it's cooling down. Tap that bowl with a wrench or equal and try it more than once. If it's stuck stuck drop the bowl carefully and see if if it's stuck high. Then again maybe it's not. I would try this first.
 

·
Registered
Joined
·
4 Posts
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?
Starts, as soon as it gets warm looses power and stops. First time it happened it back fired real hard.

I cleaned out the fuel line from the filter on, flushed out the carburetor, cleaned it and reassembled. Found some debris on the outside of the fuel filter, minor in the bowl, everything else was open and clean.
On the airfilter outlet was some sticky stuff.

Bike started after three tries and ran for 3 minutes, lost power temporarily, recovered ran for another minute and died again, this time no backfire.

Anyone have a clue what to try next?
Sorry, i screwed up a post. anyway. Sure sounds like a stuck / partially sticking float. Run it till it warms then tap the side of the carb bowl. Don't be too soft or too hard. If the float is stuck as if it had a full bowl once gas runs out it obviously will sputter out and may backfire. Tap that bowl with a wrench or equal and try it more than once. If it's stuck stuck drop the bowl carefully and see if if it's stuck high.
 
1 - 20 of 22 Posts
Top