Author Topic: "Prime" left on all night (Read 6425 times)

blue_on_black · « **on:** September 11, 2005, 03:21:30 PM »

I let my dad use my 600 Bandit last night, but told him it was low on gas and the petcock was on "reserve". So he filled it up (with premium, as I instructed him to do) and switched the petcock over to "primer" and there was gas under the bike on the garage floor today.

I brought it down to the edge of the driveway and more gas leaked out a small seam in the exhaust where the pipe meets the manifold.

Well the bike doesn't idle any more, and it really can't be driven unless you manually keep the RPM's up so it doesn't stall.

Will this fix itself or am I going to need to do some work?

B

fake · « **Reply #1 on:** September 11, 2005, 03:33:37 PM »

Your carbs are now over filled. You may have to take them off and dump the fuel out, unless somebody can point you to a better solution.

Daytona · « **Reply #2 on:** September 11, 2005, 03:45:27 PM »

The first thing you need to do (other than put the fuel selector to run) is to change the oil, or in your case diluted gas with oil in it! while its draining pull the tank and remove your air filter! or at least pull the plug from the liquid drain hose (by your exhaust collector) and make sure there isn't a puddle of gas in the air box. Your crappy idle is more than likely from all the fuel fumes that are in the box! after let it vent until you can ride it some where there isn't traffic incase it stales etc. If you have a air filter that uses oil to stop dirt re oil it! :sparkplug: Dads!!

89 octane is all 9 to 1 comp needs 93 is a total waist of $ and will do more harm than good! Actual 87 gives the best idle for me! And now i made & used my handy dandy PO'mans carb sinc'r!!! WOW WHAT A DIFF!!! "Thanks BanditAlleyBBS"

Red01 · « **Reply #3 on:** September 11, 2005, 05:01:39 PM »

And on your future gas purchases, go with a lower octane, the B6 doesn't want premium. It will run better on the cheap stuff.

blue_on_black · « **Reply #4 on:** September 11, 2005, 05:12:50 PM »

Thanks all for the insight. I guess I'm going to start with an oil change and check out the air filter..

On another note, i guess I always figured the higher octane is what a high performance machine wants. .. anyone else have an opinion on the matter?

Brian

Vee Dub Nut · « **Reply #5 on:** September 11, 2005, 05:16:19 PM »

premium is not nessasary, that being said it wont hurt anything either....

might as well save a little money

Red01 · « **Reply #6 on:** September 11, 2005, 05:20:00 PM »

There's been a recent ongoing thread on octane...

In a nutshell, the higher the octane, the harder it is to ignite. You want to run the lowest octane you can without the fuel igniting from compression - "pinging."

The B6 & 12 motors don't have the state of tune, primarliy compression ration, to need premium.

Red01 · « **Reply #7 on:** September 11, 2005, 06:20:03 PM »

Quote from: "Red01"

There's been a recent ongoing thread on octane...

That thread would be right here.

Maybe running premium won't hurt anything - like running too low an octane will, but you aren't getting the most out of the motor. I could also make a hard to start motor even harder to start.

Desolation Angel · « **Reply #8 on:** September 11, 2005, 08:34:18 PM »

Definitely read the octane thread noted above. Great info. Don't miss it.

blue_on_black · « **Reply #9 on:** September 11, 2005, 10:19:31 PM »

Thanks everyone! Your advice was priceless... I drained the hose near my exhaust and alot of gas came out. It appears to be just what I needed to do. I'm going to see what this community has to offer in the different forums.

ldbandit76 · « **Reply #10 on:** February 22, 2006, 05:32:21 PM »

Quote from: "fake"

Your carbs are now over filled. You may have to take them off and dump the fuel out, unless somebody can point you to a better solution.

As an aside, what keeps the carbs from overfilling during normal running? The vacuum-operated petcock will simply turn "on" when the engine's running, allowing fuel to flow under gravity into the float bowls. Obviously, it's getting sucked out of the bowls at some rate to keep the engine going, but there doesn't seem to be a limit to how fast the bowls could fill. Everything stays balanced, so it seems that there's something that "knows" exactly how fast to feed gas into the bowls, regardless of engine speed.

What is it? The float valves and the vacuum line? Something else?

Dave

Red01 · « **Reply #11 on:** February 23, 2006, 04:15:34 PM »

The floats are connected to a needle & seat setup that shuts fuel off to the bowl when it gets full and opens when the level drops.

A vacuum hose operates the petcock, as you noted. Fuel is pulled from the bowl by venturi vacuum thru the jet systems.

ldbandit76 · « **Reply #12 on:** February 23, 2006, 06:22:28 PM »

Quote from: "Red01"

The floats are connected to a needle & seat setup that shuts fuel off to the bowl when it gets full and opens when the level drops.

Okay, and what lets the carbs overflow when the petcock is left on Prime, then? Do those valves fail?

Dave

Red01 · « **Reply #13 on:** February 24, 2006, 12:34:05 PM »

Yes, that's the only way. Problem is you don't usually know they've failed until either the petcock fails open or you leave it in "Prime" with the engine off for a while.