fuel/starting issue

[bri87]

1969 Dream . Here's my puzzler. recently cleaned carb, tank and rebuilt petcock. now starter turns and turns but bike wont fire. eventually fuel starts leaking from carb overflow.

however when I hook it up to auxiliary tank, it fires immediately and runs fine - so from this I assume the carb is properly working and adjusted.

I hook it back up to its own fuel, and now it wont fire up. if I pull the fuel line to the carb, fuel comes out so it looks like this is fine - its getting fuel.

I can repeat this with the auxiliary tank, and it runs again fine until I shut it off. try again with its own tank. and nothing.

I'm just frustrated and scratching my head at this point. could I be getting fuel from but just not enough? any one else have a similar issue they tackled. any help would be appreciated.

[cadman]

The obvious question. Fuel in the tank same as auxiliary fuel? Was the tank purged well after cleaning? If just a slight amount of the chemical that was used to clean the tank was not purged it could be the problem. Water settles to the bottom and is first to the carb. I usually drain some fuel from the tank into a glass jar and look for moisture.

Is the auxiliary tank higher than the stock tank? I have a fuel bag I hook to the ceiling making it quite a bit higher than the stock tank. This creates additional pressure (not much) on the needle and seat so they leak.

I have also had problems with the float sticking at the bottom of its stroke. The float drops to far and hits the needle at an angle and won't push it up. Particularly bad on early Honda 4's.

[bri87]

1. the fuel is the same, as I thought of this also.
2. interesting point regarding the pressure. my auxiliary tank is as you describe hung higher than the actual tank. I also noted that the fuel flow is greater. I'll try lowering this and see if the same thing happens.
3. I'll definitely check the float height again.
thanks

[ggarton]

Have you tried it with the petcock turned to resereve.

[Nick]

Don't forget the No. 1 of troubleshooting! When you're certain it's a fuel problem, it's electrical, and vice versa.

Is the fuel tank pinching the wiring loom somewhere or causing a wire to ground out?

Tank pinching the throttle cable, etc.

[rrietman]

Petcock rebuild? that can be a problem. most of the kits out there will swell up and block most of the fuel flow. you can pull a fuel line, see flow, but it's not enuf to overcome a float valve resistance. it will act like you are out of fuel. pull the fuel valve a part and look at the seals. the only kits I have had good luck with come from "peanut" on ebay.
Good luck
Randy

[bri87]

after trying and considering the above. I think it is the fuel petcock. I think I will order a new aftermarket one and install. if it fires up, that should identify the problem. then I can work on fixing and reinstalling the original.