Yes the vacuum pump with a chaffed diaphragm can both fill the float bowls and flood the crankcase. I chased that very situation with my Kawasaki way back when....blew two race weekends until I figured it out. Engine would actually run with the carb on the vacuum port side removed from its mounting boot.
Chuck McAbee SEDIV #16 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Kenneth Kirkland Sent: Sunday, February 25, 2007 10:17 AM To: [email protected] Subject: RE: [F500] Re-firing rebuilt 494--Update Chuck, I'm saving starting fluid for an absolute, drop dead, last resort. I have a can, but haven't used it yet. The motor has a vacuum fuel pump. I'm getting fuel to the carbs. Would a chafed diaphragm fill the carb float bowls AND flood the crankcase through the pulse port? Kenneth --- "McAbee, Chuck" <[EMAIL PROTECTED]> wrote: > What kind if fuel pump is being used....vacuum or electric. > > Is ether being used for starting fluid? If so you my be running > several revolutions on the ether and then starving for fuel because it > is not being supplied from the pump. > > Batteries can fail (ground out internally) from our engines vibrations > over time causing the electric fuel pump to quit....the vibrations > stop and the battery works again. > > Vacuum pumps can fail because of a failed pump diaphragm...there can > be a 'catastrophic' diaphragm failure where nothing gets pumped, or > there can be a maddening chaffed diaphragm where the vacuum from the > crankcase that operates the pump draws fuel through the diaphragm and > floods the crankcase. > > I takes 3 things to make the engine run....Fuel, air and a properly > timed spark. > > > Chuck McAbee > SEDIV #16 > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] > On Behalf Of Kenneth > Kirkland > Sent: Saturday, February 24, 2007 5:08 PM > To: [email protected] > Subject: [F500] Re-firing rebuilt 494--Update > > Hello all!! > > Thanks again for all of the ideas on re-firing the motor. > > Out of semi-desperation, I installed 2 brand new carbs on the motor. > It seems to have helped, but it's still not starting and running. It's > more consistent about firing through 2 or 3 revolutions before it > stops. > Different throttle settings and different idle air mixture settings > don't seem to help or hurt much. > > Has anyone seen a similar situation? > > Kenneth Kirkland > #18 MiDiv / Arkansas Region (77) > 1991 KBS Mk. V > www.kirklandracing.com > ----------------------------------------- > This email transmission and any accompanying attachments may contain > CSX privileged and confidential information intended only for the use > of the intended addressee. Any dissemination, distribution, copying > or action taken in reliance on the contents of this email by anyone > other than the intended recipient is strictly prohibited. If you have > received this email in error please immediately delete it and notify > sender at the above CSX email address. Sender and CSX accept no > liability for any damage caused directly or indirectly by receipt of > this email. ________________________________ FormulaCar Magazine - A Proud Supporter of Formula 500 The Official Publication of Junior Formula Car Racing Subscribe Today! www.formulacarmag.com or 519-624-2003 _________________________________ _______________________________________________ F500 mailing list - [email protected] To unsubscribe or change options please visit: http://f500.org/mailman/listinfo/f500 *** Please, DO NOT send unsubscribe requests to the mailing list! ***
