He was using the leakdown tester to set the barrel valve ( non electronic
fuel injection system enriching devise). This is a great way of getting a
baseline flow to the injectors, then you can let the motor warm up and
readjust the barrel valve to get the proper balance. Hope that answers
your question.
joe
Bill Bennett wrote:
> Joe help me out here I kinda remember seeing someone who ran a Top
> Alcohol Funny Car use a leak down tester on his fuel injector system.
> What was this for and what was he doing?
> Bill Bennett
> ----- Original Message -----
> From: "Joe Timney" <joetimney@dol.net>
> To: <V4GR@aol.com>
> Cc: <BICWIG@aol.com>; <kturk@ala.net>; <land-speed@autox.team.net>
> Sent: Monday, August 28, 2000 2:38 PM
> Subject: Re: Leak Down Tester
>
> > What you are looking for is the delta between the two gauges.
> Setting the first
> > gauge at 100 psi allows you to simply read the second gauge as a
> percent.
> > Example, If the first gauge reads 100 # and the second gauge reads
> 96 #, then
> > the leakdown is 4 %. If you only have say 80 lbs. of air from your
> compressor,
> > you will have to do some math to arrive at a percentage of loss. I
> have found
> > that a motor with gap-less rings will show 0 to 1 % leakdown if in
> good working
> > order. 4 to 6 % is not too bad. The motor needs work if you see over
> that. I
> > have tested motors with the piston in various postions in the bore
> looking for
> > scarring or bore scratches. I have had a fuel motor on more than
> one occasion
> > show good on the leakdown but the piston was melted down around the
> rings.
> >
> > joe
> >
> > V4GR@aol.com wrote:
> >
> > > Keith; I don't know why but when I was going to A&P school we
> learned to set
> > > the gages at 80 lbs. Then we compared the reading on the
> downstream gage
> > > after opening the air valve. I seem to remember 20% for a worn
> cylinder cold
> > > was acceptable. More than that was not. Race motors should be much
> tighter.
> > > After the first few years at the airline we put away our leakdown
> testers.
> > > Couldn't get them to read correctly on a JT3. Rich
> >
> >
> >
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