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Fuel system problem

Here is a cheap gauge that will probably do what you need it to do. Albeit not high quality it will probably work for a good while for the average guy.

FUEL TOOL Fuel Pressure Gauge

Take your bike for a ride come home and hope it fails in the driveway and go to work with this. It may keep you from buying unnecessary parts. If it works out you could probably recoup some of your money by putting the gauge for sale on this forum.....
 
You said on the original post that the fp cycles. Is that for about 5 seconds and then stops? If so, that is the fp charging the fuel system to pressure. If you leave it on without cranking it over for a few minutes, does the fp cycle again? That would indicate a probably leak in the system.

When I had my '03 UC, I had three separate leaks of the infamous convoluted tubing inside the tank. Twice on the long tubing and once on the short one. I finally gave up fighting the fuel pump/regulator/filter assembly in and out of the tank and replace ALL the tubing with high pressure reinforced fuel hose from one of the auto parts stores. That took care of all that! But while in there I replaced the fuel filter and fuel pressure regulator. As long as the pump housing is not cracked, I think you do not need to replace that.

Unfortunately the "sock" on the pickup side is not replaceable. At least I couldn't find a replacement for it. So I just cleaned it as best as I could with carb spray when I had it out of the tank.

This stuff is not hard to do, just a pain getting the stuff out of the tank. The assembly does hinge to make it a bit easier. I always drained the tank as much as possible since it is easier to replace the discharge tubing with the fuel hose when that is out of the tank to work on it.

Good luck with your issue.

Cheers,

TQ
 
You said on the original post that the fp cycles. Is that for about 5 seconds and then stops? If so, that is the fp charging the fuel system to pressure. If you leave it on without cranking it over for a few minutes, does the fp cycle again? That would indicate a probably leak in the system

Good luck with your issue.

Cheers,

TQ

The fp cycles and stops. Never let the ignition on after cycling without starting so i don't know if it would cycle again, I will try it.
The fp w/screen, filter and short hose were replaced in the spring just after this problem started to occur.
 
The fp cycles and stops. Never let the ignition on after cycling without starting so i don't know if it would cycle again, I will try it.
The fp w/screen, filter and short hose were replaced in the spring just after this problem started to occur.

At that time did you inspect/test the discharge tubing (long one) to make sure there were no pin holes worn through it? The best way I found to do this is to blow in the top end of the tubing when the rest of the stuff is out of the tank to see if it makes any bubbling sounds (if there is gas in the tank, or a slight whistling sound in the air. Visual inspection is difficult. Hard to see the pin holes especially in the tank. But if there is a small pin hole in that convoluted tubing it can effect the pressure in the fuel system especially when the gas level in the tank is low.

I think if you go the pressure gauge route, you will be able to see a drop in the fuel pressure once the system first charges up but before cranking the engine. Just let it sit after the fuel system charges up and watch the gauge to see if the pressure drops off slowly. If so, there are probably pin holes in there or the regulator is suspect. Either way, you will probably have to drag all that stuff back out of the tank again!!!

Cheers,

TQ
 
I only inspected the long tube visually, as you said it was difficult. I did however watch in the tank as the fuel pump charged the system and did not see any fuel movement or bubbles.
This is an intermittent problem that only occurs when the engine is hot, if there was a hole in the tubing wouldn't the problem occur all the time?
 
HD06FLHR055.gif

#6 is the regulator, if it is bleeding down this could be the problem @ under 40.00 I would be looking at it early models were plastic with a diaphram
 
You said this happens when the engine is hot?
HD06FLHR013.gif

Check and or replace # 7
 
I looked at a regulator from Slick Customs made in the USA, $116. and a regulator holder [part #18] made from billet aluminum, $48, not plastic like the oem.
Where did you see the $40 one?
What is # 7?
 
Just thought I would get back and say I think I got the problem fixed. I put in a new filter, pressure regulator and holder and a new hose.
Rode 100 miles yesterday, stopped and started the engine several times with no problem. Thanks for all the help!
 
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