In-line check valve plans

[hcrotalus]

I am looking for plans/construction articles on building an in-line fuel check valve for hit miss engines. I seem to recall seeing an article in Strictly IC or Home Shop Machinist or online or possibly even in one of Kozo’s books but I can’t seem to find it now.

Anyone know?

Thanks
Todd

 

[deverett]

Here you are Todd.

Just use a straight connector instead of the elbow at the bottom. Adjust the size as required.

Dave
The Emerald Isle

 

[hcrotalus]

Hey thanks! Just what I was looking for!

So there are no springs used? What about the seat for the ball? Anything special there?

Thanks
Todd

 

[Brian Rupnow]

Best trick in the world for that. Machine the ball seat to be a sharp corner with no chamfer or radius on it. Put the piece in a vice and drop a sacrificial ball down into it (Same size as finished ball) , put a long nosed punch down the hole against the top of the ball and give it a good whack with a hammer. Throw that ball away and put in the ball you are actually going to use. I have made many of these, and if the bore on your engine is any smaller than 1" diameter, then use a 3/32" diameter ball. If you use anything larger, the vacuum created by the carburetor venturi may not be strong enough to lift the ball of it's seat and let the gasoline flow.

 

[aka9950202]

I would suggest you visit Jan Ridders website. He offers the plans for free.

Cheers,

Andrew in Melbourne

 

[mrehmus]

Another trick is to use very small tubing. The surface tension of the gasoline will prevent it from running back down the tube.