Mountain Machine

FUEL VALVE VACUUM BYPASS
This page was last updated: April 2, 2023
Copyright 2008 Mountain Machine Design
MOUNTAIN MACHINE & MOTORCYCLE

Specializing in custom CNC machining.& Harley Davidson service and parts.

Evergreen, Colorado

303-862-8803
A common problem on a lot of carbureted Harleys is the vacuum fuel valve, designed to eliminate the need to turn off the fuel valve when not in use by using the vacuum of the engine to turn the gas on. 

These fail frequently and can cause intermittent problems like stuttering, lean backfires and poor high rpm performance or being stuck on the side of road. Most of the time it'll start running fine again leaving you not able to troubleshoot the problem. We've designed this easy bolt on kit to eliminate the vacuum portion of the valve so it operates as any other standard fuel valve and eliminates the associated problems with vacuum fuel valves.

Remove the 4 screws on your stock valve, remove the diaphram, then using your existing hardware, bolt on the plate provided (it's best to drain the gas tank first but not necessary if you are carefull not to remove the valve portion itself). You will need to cap the vacuum line as well.
That's it problem solved!   


                                 
                                  $21.99 
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shop packs of 5 or 10 available at discounted prices, call for price