[F500] Carb question

[bosco]

I would suggest trying a pulse pump.  If it corrects the problem, put your
electric pump on a switch, so you can use it for starting purposes.  Its
probably not the pump, but it couldnt hurt to try.



----- Original Message ----- 
From: "George Harmuth" <harmug at us.ibm.com>
To: <f500 at f500.org>
Sent: Thursday, September 16, 2004 8:52 AM
Subject: [F500] Carb question


> Morning all, I have a problem with one of my carbs, I can't get it stop
> dumping fuel out the overflow. This is a recurring problem that comes and
> goes for no reason I can figure out and I'm hoping some one here has seen
> this before. Motor is a Kawi with an electric fuel pump, fuel pressure is
> 4-6 PSI, direct feed no regulator or bypass.
> Symptoms:
> At idle fuel dumps out the overflow and I assume down the carb in a good
> stream. By the way, this problem only happens on one carb, the one
farthest
> away from the fuel pump, the other carb has no problems.
>
> What I've done:
> Replace floats, needle valve assembly, gaskets, fuel bowl, fuel filters
> (one per carb), Checked float height and tried different height settings,
> currently set to close valve when lever is horizontal. Floats have tabs on
> the bottom facing each other.  Filled fuel bowl and let floats soak for a
> while, both still floating after 10 minutes. Manually blew air into fuel
> inlet, valve does seal off inlet. Disassemble entire carb(s), clean,
> inspect for cracks, remove and inspect jets (both carbs same jetting,
> primary and secondary were different but the same between carbs, but I
> don't remember the sizes right now)
>
> Switch the valve asembly, fuel bowl, floats, lever asm, one at a time from
> between the 2 carbs to see if the problem traveled with a certain part:
> Results, same carb always leaks, other one stays OK
>
> My suspicion is the fuel pump just forcing gas past the float once it
tries
> to close and the pressure keeps rising. I was going to put the old vacuum
> pump back on, but I'm leery about hard starting after the car has been off
> for a while.
>
> Does anyone have any ideas? Do I just bite the bullet and get a new carb?
> Do folks with electric pumps have some type of regulator or pressure bleed
> installed? Start looking in the classified for a Rotax motor :)?
>
> Second question, anyone going to the Watkins Glen for the Fun One this
> weekend?
>
> thanks
> mike
> Zink #73
> _______________________________________________
> F500 mailing list - F500 at f500.org
> To unsubscribe or change options please visit:
> http://f500.org/mailman/listinfo/f500
> *** Please, DO NOT send unsubscribe requests to the mailing list! ***