`94 FXDS has an Issue, Your Help; Appreciated

[deadzoo]

First I should say that I`m not a motorhead. I really want to be , but not even close. I have tried everything that I know to fix it and have spent almost a week on the internet a few hours each day trying to diagnose and resolve the issue myself to no avail. I realize that you guys have lives and have much more important things to do than to help me. By knowing this, I assure you that your help will not be taken for granted and your time and efforts will be greatly appreciated.

The bike cold starts right up without using the enrichener, just a couple pumps on the throttle, hit the starter. Idles smooth, throttle very responsive, ride a mile or two runs strong then suddenly I`ll feel a little sputter or two then it starts rapidly losing power and starts repeatibly surging and backfiring out of the carburetor until it totally shuts down. The time between the first sputter and shut down is between about 30 seconds and one minute. Now here`s the part that to me seems most odd, wait a couple, three minutes and it will fire right back up and runs great for a mile or two then the process repeats itself. Another thing, not sure if it matters , but it seems like the longer I wait to start it up again, the further I can go before it begins again.

Have any thoughts, suggestions, advice etc..? I would bet the farm that I have neglected to include some important information that would help you solve the problem. Please let me know what you need and I`ll get the information to you asap.
Long days and pleasant nights,
Rod

 

[SledDog]

Have you checked the fuel system? Is there an external fuel filter that may be clogged? Does it happen when under power only or do you see this while idling also?

Is the ignition system stock? If so, HD had an issue with cam position sensors during that era. My 96 FXD had the same issue. It got progressively worse. Since it was intermittent, and the dealer could not diagnose it. I had it happen one today just before pulling out of the driveway. So while it was in failure mode, I broke out the service manual and was able to track it down by doing the ignition system testing listed in the service manual. The cam position sensor is a Hall Effect type. When the sensor heats up, it malfunctions. When it cools off, it works normally.

Do you have a manual?

 

[Bodeen]

Like Sleddog, It sounds like a heat issue. Removal of the carb and a thorough cleaning is never a bad idea. Its possible that the float has an issue and not keeping the proper fuel level in the bowl.

 

[deadzoo]

Hey SledDog,
Thanks for your reply, very good information. The fuel system,; I had the carb cleaned, replaced the enrichener cable and flushed the tank. It does have an external in-line filter, I didn`t replace it because gas seemed to flow through it unrestricted. I`m feeling a fool at the moment, could it be that simple. I don`t think so, but replacing it is now at the top of my list of to do`s.
I don`t know if the ignition system is stock, Probably is though, everything else is. I never heard of a Hall Effect sensor. My previous Harley`s were a chopped 1970 FLH and a 1976 Ironhead, both with points and kickstarts. This is the only electronic ignition I`ve ever owned. My bro`s back home in Tennessee (I`m in California now) told me over and over to "keep it simple" and I did as advised. Are these Hall Effect sensors expensive? Difficult to replace? I`ll probably have these answers once I`m finished with this post, I`ll be searching duckduckgo and google for info.
And finally, no I don`t have a service manual for this bike. I kind of surprised I have not stumbled upon a download link. I have been looking on ebay and amazon, but haven`t pulled the trigger yet.

Forgive me for asking a stupid question, but will a bad float fail with the kind of consistency that is being demonstrated by these symptoms? No disrespect intended, I`m just having a mental block trying to understand. I appreciate and value you advice and I will not hesitate to try all these suggestions. My biggest problem is I`m way out of my element and way, way out of my comfort zone with this bike. Fortune favors the bold, right? On the flip side of this proverbial coin is, stupid people walk.

 

[joel]

I am sure you will figure this out, and I will toss in a thought.
These symtoms can be both electical or fuel.
Cam and or crank sensors do become affected by heat as well as a ignition contol module, so check into those for sure.
On a side note. My snow blower had the exact same symptoms and it took a little while to find the cause.
Turned out it was running out of gas.
I would check the level in the tank, put the cap back on and get a few minutes of work and it sputtered and dies.
Turned out it was running out of gas. Not do to volume but vacumm. See the cap wouldn't vent anymore do to age of the rubber seal on it. After some gas drained from use the vacumm acted like a shut off valve.
Try leaving the cap loose and ride it. See what happens.

 

[Breeze3at]

First off, I give you credit for knowing how to spell carburetor. I get it right only occasionally. Hall effect sensors are basically magnetic fields interrupted by a trigger. You can find stock ones on ebay cheap, but I'm not thinking that direction. You say fuel flows unrestricted. How long? You may have a pinched vent line and the tank is pulling a vac. and stops flowing. Loosen your gas cap and see if it helps. If you are running less than 1/3 tank of fuel, the crossover line may be restricted. Also, your fuel petcock has a nylon screen filter over it (inside tank) they can clog and stop flow. Have you tried riding with the petcock in reserve position? Do not hesitate to make long replies or ask what you think is a "stupid" question. The more information you supply, the better to diagnose your problem.
P.S. We don't always agree on cause/effect, that's what makes for successful problem solving.
Looks like Joel and I were typing at the same time.

 

[deadzoo]

Joel,
I switched gas caps just prior to it acting up. Before work I`m going to put the other cap back on and see how many times I can make it around the block.

Breeze3at,
I did not even think about the filter on the petcock when I flushed the tank. I did try reserve, what I didn`t try was loosening the gas cap.

Thanks a lot guys. The sense of impending doom that I have been feeling has lifted some, I`m actually exited to try these suggestions. I`ll keep you updated on my progress.

 

[Bodeen]

Forgive me for asking a stupid question, but will a bad float fail with the kind of consistency that is being demonstrated by these symptoms? No disrespect intended, I`m just having a mental block trying to understand. I appreciate and value you advice and I will not hesitate to try all these suggestions. My biggest problem is I`m way out of my element and way, way out of my comfort zone with this bike. Fortune favors the bold, right? On the flip side of this proverbial coin is, stupid people walk.

Trash in the valve that the float controls can cause all kinds of problems that do not make sense. Now that you have stated the carb has been cleaned. It may not be the issue at all. If its fuel related and its a lean condition, you should be able to pull the enrichener while its acting up. That would cure a lean condition and you could then rule that in or out.

 

[deadzoo]

Bodeen,
I did try pulling the enrichener out while it was acting up, not because I knew anything about lean fuel, I did it totally out of desperation. Thank you for sharing this, it`s good to eliminate another possibility.

 

[Bodeen]

What as the result of pulling the enrichener while it was acting up? Better, worse, same....If it didnt help, I would be headed down the heat issue path.