Home Made Vacuum Gauge Synchronizer
by Bill Murrin
I have made a cheap carb synchronizer out of a vacuum gauge, 3/16ths" tubing, four screw aquarium valve and a home made plenum. The gauge($8) is from Harbor Freight and the aquarium valve($4) is from my local fish store. The plenum tank is just PVC pipe with a couple of brass taps screwed into it($3). The plenum was used to
dampen the fluctuation of the needle on the vacuum gauge.
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Here is one of the brass plenum fittings:
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Closer shots of the gauge and valve:
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Operation: Adjust each carb by turning on the valve that is connected to it's manifold while the other three are closed. This takes a little longer than the mercury sync but it is cheap and you can open the throttle as much as you like without worry of ingesting mercury.
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Name: 20020830-synchroinuse.jpg
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ID: 860326"
If I had it to do over again I would make the plenum out of larger diameter PVC and have a threaded cap on one end so all the parts would fit inside.
by Bill Murrin
I have made a cheap carb synchronizer out of a vacuum gauge, 3/16ths" tubing, four screw aquarium valve and a home made plenum. The gauge($8) is from Harbor Freight and the aquarium valve($4) is from my local fish store. The plenum tank is just PVC pipe with a couple of brass taps screwed into it($3). The plenum was used to
dampen the fluctuation of the needle on the vacuum gauge.
Here is one of the brass plenum fittings:
Closer shots of the gauge and valve:
Operation: Adjust each carb by turning on the valve that is connected to it's manifold while the other three are closed. This takes a little longer than the mercury sync but it is cheap and you can open the throttle as much as you like without worry of ingesting mercury.
If I had it to do over again I would make the plenum out of larger diameter PVC and have a threaded cap on one end so all the parts would fit inside.