ZAMA C3-E9

[mirage]

I am working on a John Deer chainsaw that is made in Italy. It has a Zama C3E9 carb on it. This saw ran but I thought it need to be rebuilt.When I was rebuilding it I noticed there was not a gasket between the diaphragm and the carburetor. It just had the diaphragm on that side of the carburetor. The Saw will run with out the gasket under the diaphragm. When you install the gasket it will not start. Also the primer bulb does not work and does not get gas into it when you prime it. When the saw runs the bulb will fill up with gas. Anyone ever heard of not using the gasket under the diaphragm ? Thank you for any info regarding this.

 

[Steve]

I am working on a John Deer chainsaw that is made in Italy. It has a Zama C3E9 carb on it. This saw ran but I thought it need to be rebuilt.When I was rebuilding it I noticed there was not a gasket between the diaphragm and the carburetor. It just had the diaphragm on that side of the carburetor. The Saw will run with out the gasket under the diaphragm. When you install the gasket it will not start. Also the primer bulb does not work and does not get gas into it when you prime it. When the saw runs the bulb will fill up with gas. Anyone ever heard of not using the gasket under the diaphragm ? Thank you for any info regarding this.

Your metering lever is too low. When you put the gasket in there it will raise the diaphragm substantially. Pulling it away from the lever. Also check that you have the hoses in the correct spot on the carb and the purge bulb.

 

[Stump Shot]

I am working on a John Deer chainsaw that is made in Italy. It has a Zama C3E9 carb on it. This saw ran but I thought it need to be rebuilt.When I was rebuilding it I noticed there was not a gasket between the diaphragm and the carburetor. It just had the diaphragm on that side of the carburetor. The Saw will run with out the gasket under the diaphragm. When you install the gasket it will not start. Also the primer bulb does not work and does not get gas into it when you prime it. When the saw runs the bulb will fill up with gas. Anyone ever heard of not using the gasket under the diaphragm ? Thank you for any info regarding this.

I've seen one other saw with this phenomena going on. Was an older Shindawa with a Walbro carburetor on it. Sure enough if you looked at Walbro specs and did it that way it was wrong, the Shindawa specs showed it on the opposite side(of every other carburetor in the world) and that's where it ran good and yes the needle valve lever was set to spec as well.
I would ask Ray Benson if he has the IPL and Repair manual for the model saw you have or the original manufacturer equivalent.

 

[mirage]

I checked the hight of the needle valve. It was level with the face of the carb.

 

[mirage]

Thanks Stump. I will get all the info on the saw and pass it along.