Steve Saunders Goldwing Forums banner

Status
Not open for further replies.
1 - 6 of 6 Posts

·
Premium Member
Joined
·
475 Posts
Discussion Starter #1
imported post

I took the fuel line off my petcock and turned the petcock to 'on.' I heard a 'psshhh' sound, and no gas. Opened the fuel cap, and gas flowed. I'm assuming that means i have vapour lock in the tank, and the cap isn't vending? The cap is discontinued -- can i 'clean' it out to get it venting? I don't see any other tank vent, apart from the overflow tube.
 

·
Premium Member
Joined
·
2,491 Posts
imported post

mag wrote:
I took the fuel line off my petcock and turned the petcock to 'on.' I heard a 'psshhh' sound, and no gas. Opened the fuel cap, and gas flowed. I'm assuming that means i have vapour lock in the tank, and the cap isn't vending? The cap is discontinued -- can i 'clean' it out to get it venting? I don't see any other tank vent, apart from the overflow tube.
Mag, what are you working on here? Some caps are vented, a lot aren't & rely on the emission system to vent the tank & capture the fuel vapors. If you don't see another vent line it probably does vent through the cap. Let us know if you have a California emission bike.

In any case you should be able to clean your cap vent if it has one.

Twsity
 

·
Premium Member
Joined
·
475 Posts
Discussion Starter #4
imported post

Hi Twisty, working on a sluggish cold start. Have to 'pump' the throttle or starter to get it to start, then it fires up and idles very well. It's not electrical -- new points, timing is on, battery good. If i'm restarting the bike, no problem, fires up right away.

I took a look at the air filter for clogging, and noticed gas in the carb air box down below. I suppose this explains why plug #1, out of all the others, is fouling black -- unburnt gas? All my other plugs read normal, and i had 40mpg the other day.

Maybe i dislodged some more gunk in the tank (after cleaning it out) and it stuck a float and flooded #1 carb bowl? I drained the bowl anyway. Mystified. Is that sluggish start and the flooding related to vapour lock? IE, flooding the carb plenum with gas to get flow-through. Maybe i should replace the fuel filter again?

Everything is new on this bike - plug caps, air-cut valve, carbs were rebuilt by Honda before i installed them...

The bike doesn't have a vapour canister, but it does have a crankcase breather hose, which goes to airbox, then vents back out a hose to atmosphere. Would this restrict airflow in the box? I wouldn't think so, as it doesn't affect air intake...Since the bike has new carbs, new pipes with baffles, new points, the only remaining carry-over from before is this emmission breather routing -- it's all i can think of, except for crud still getting in the fuel system from rusty tank?
 

·
Premium Member
Joined
·
2,491 Posts
imported post

mag wrote:
Hi Twisty, working on a sluggish cold start. Have to 'pump' the throttle or starter to get it to start, then it fires up and idles very well. It's not electrical -- new points, timing is on, battery good. If i'm restarting the bike, no problem, fires up right away.

I took a look at the air filter for clogging, and noticed gas in the carb air box down below. I suppose this explains why plug #1, out of all the others, is fouling black -- unburnt gas? All my other plugs read normal, and i had 40mpg the other day.

Maybe i dislodged some more gunk in the tank (after cleaning it out) and it stuck a float and flooded #1 carb bowl? I drained the bowl anyway. Mystified. Is that sluggish start and the flooding related to vapour lock? IE, flooding the carb plenum with gas to get flow-through. Maybe i should replace the fuel filter again?

Everything is new on this bike - plug caps, air-cut valve, carbs were rebuilt by Honda before i installed them...
Mag, if you have a vacuum in your tank when parked it could limit the amount of fuel available at start up. You would think there should be enough fuel in the carbs for a decent start but you never know.

As a test, try loosening the fuel cap just before engine shut-down & see how it starts the next day.

Twisty
 

·
Premium Member
Joined
·
475 Posts
Discussion Starter #6
imported post

That was my thought, too -- that fuel in floats would start it up, then fuel pump would suck gas through. Maybe my fuel filter is plugged? It was new just before i cleaned the tank. I wouldn't think that 50 miles between when it was replaced and when i cleaned the tank would make a difference.

What about the flooding in #1, and comments re: breather hoses?
 
1 - 6 of 6 Posts
Status
Not open for further replies.
Top