Can I add a pulse port?

wml52

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I have an old generator with a Tecumseh HM100 engine. I would like to add an auxiliary fuel tank to extend the generators run time using a pulse port fuel pump and fuel selector valve. My thought was to fabricate a carb spacer with a pulse port and run that to the pulse pump. My question is can I place the spacer on the front of the carb rather then the back end. Doing so will eliminate having to make a custom governor link due to the carb being extended further away from its original position.

Does this seem feasible? Any help or suggestions would be appreciated.

Thanks to all
 

AVB

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It would better to drill, tap, and install a barbed fitting for the 1/4 id fuel line in the crankcase. I know more work as got remove the metal bits from the crankcase but it is better. This OEM manufactures did it on the L head engines the I have worked on with these vacuum fuel pumps.

The reasoning is that you more impulses and you not changing the intake design that you must compensate for. With an intake port you only getting a vacuum pulse only on the intake stroke. Where with a crankcase you getting both vacuum and pressure during the four strokes ( 2 vacuum, 2 pressure). The vacuum fuel pump needs to operate correctly.
 

wml52

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Any suggestions as to best location on the crankcase?
 

cpurvis

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The crankcase probably already has a breather tube. Tap into it.
 

bertsmobile1

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Check around to see if there is a dip stick tube with a take off .
You are taking crank case pressure pluses.
 

wml52

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The crankcase probably already has a breather tube. Tap into it.
It does have a breather however the tube is connected to the reed valve which I believe is a one way valve, like a check valve. If that is the case wouldn't It only provide positive pressure and not negative?
 
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