4 stroke carburetor selection

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I have a vintage Briggs & Stratton 5s, similar to the one in the attached picture. However, my carburetor and gas tank are long gone. I would like to run this engine using a more modern setup, which would include a stand alone gas tank and hose running from the tank to a carburetor. I have already made one attempt, which failed. I tried to use a standard briggs and stratton carburetor, which I hooked up using an intake manifold, which I fabricated. The engine would not run. Some gas got into the oil, so I am assuming too much fuel. The carburetor I tried has no gas or air adjustment screws and is for a 5 hp motor. The 5s is 1 hp. I got the engine running for a few seconds using starting fluid. Can anyone recommend a carb for this situation. Again... I do not want an original 5s carb.

Thanks in advance.

Jim

Screenshot_20170807-145540.jpg
 
Hi Jim,

A Suffolk Punch / Colt carburettor will do the job you require, but you will again need to make an adapter for the manifold as the mounting angle of the bolts is at a different angle.


th
 
You can use a regular chainsaw carburetor,
you have 2 choice
#1 Keep the fuel pump of the carb but you will have to drill
a hole 1/8 ID in your block to put a fitting for the pulsation

#2 remove the pump diaphragm and place your tank higher than your carb.

This will give you Low speed fuel adjustment and hight speed adjustment.

a 60cc carb should work just fine. If you look at the picture You will need the pulse tube if you go with #1
other wais it doesn't matter
good luck

chainsawcarburatorwith mod.jpg
 
You can use a regular chainsaw carburetor,
you have 2 choice
#1 Keep the fuel pump of the carb but you will have to drill
a hole 1/8 ID in your block to put a fitting for the pulsation

#2 remove the pump diaphragm and place your tank higher than your carb.

This will give you Low speed fuel adjustment and hight speed adjustment.

a 60cc carb should work just fine. If you look at the picture You will need the pulse tube if you go with #1
other wais it doesn't matter
good luck

Most chainsaw carbs would be 2 stroke, I'm guessing. Do I need a 4 stroke carb?
 
No all a carb does is manage fuel delivery/ air fuel ratio.
they don't know if it;s 4 stroke or 2 stroke. This is where the pulse line is important
A carb respond to pressure differential, no matter 4 strokes or 2 strokes.There is a Pulse it will
(the carb) respond
 
Hi Jim,

A Suffolk Punch / Colt carburettor will do the job you require, but you will again need to make an adapter for the manifold as the mounting angle of the bolts is at a different angle.


th

That's a great looking carborator. Thanks!
 
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