Looks like I have still got my facts wrong.
Con Air does apparently stock the carb balancing meters as well as Skydrive.
The Con Air catalog can be downloaded from
http://www.conairsports.co.uk/downloads/CATALOGUE.pdf
The balancer (including photo) is at the bottom of the page.
----- Original Message -----
From: "Carl Pattinson" <carl@flyers.freeserve.co.uk>
Subject: Re: Carb Balancing - Flow Balancer?
> Before I started trying to balance my carbs using the vacuum guage method
I
> tried it using a flow based meter. This was a Synchro Test meter (with the
> ball floating inside the tube). This meter is the one suggested in the
> official Rotax manual and is made in Germany.
>
> I found this method pretty unsatisfactory as you have to hold the Synchro
> unit against the carb opening while a rapidly whirling prop is threatening
> to chop you up. You have to move from side to side to match up both carbs
> with the single meter. This is ok while the engine is idling but pretty
> scary at 4000 RPM and needs constant reajustment to keep the ball in the
> centre of the column. Im not even sure it would work at high RPM due to
the
> increased airflow.
>
> As I said before the vacuum guage method (using a matched pair of guages)
is
> by far the best and easiest method. Once the idle balance was set, running
> the engine up to mid range still produced a fairly closely matched vacuum.
> It was then only necessary to adjust the cable collar nuts on one of the
> carbs very slightly to even up the pressures. In our case this required an
> ajustment of two flats (six flats being one complete tuen of the ajusting
> nut)
>
> My personal feeling is that the engine is best balanced at about 4000 RPM
> which is where the engine runs most of the time. I found that once we had
> balanced at this speed (having first set the throttle stops), the engine
> idle balance was fairly close and ran smoothly. The trouble is that you
dont
> realise how roughly your engine might be running until you synchronise the
> carbs properly. A badly balanced engine will probably stop running below
> 1500 RPM whereas when the carbs are set properly you can drop the speed to
> as low as 1000 RPM and the engine will still tick over.
>
> If the engine dosen't run smoothly at tickover and you have to increase
the
> throttle setting to eliminate any rough running then it almost certainly
> needs retuning and balancing.
>
>
> ----- Original Message -----
> From: "Peter Zutrauen" <peterz@zutrasoft.com>
> Subject: Carb Balancing - Flow Balancer?
>
>
> > I was wondering what is wrong with using a simple flow-based carb
> > balancer? Years ago when I was playing with my 'hopped-up' VW beetle
> > with dual carbs, this tool worked very well to balance the carbs. Just
> > dial the restrictor to center the ball on one carb, then move to the
> > other carb and check the ball and adjust accordingly. A few iterations
> > and you're done!
> >
> > Here is the type I am referring to:
> > http://www.datsunroadster.com/PIC_PAGES/NEW_PARTS_PIC_PAGES/999-08.htm
> >
> >
> > Opinions?
> >
> > Thanks,
> > Pete
> > A239
> >
>
>
|