[Radarguy]

Does anyone have an idea why this motor starts great but will not run slow or idle? It has a bowl carburetor. I have cleaned it and checked all of the ports and jets. It seems to me that the float is set low but I cannot find any details on it. It was given to me and I have never been able to get it to run well enough to use.

Thanks,
Russell

 

[AVB]

Russell will the model number to look up the trimmer to see what you are working on.

 

[Radarguy]

Yes, The model number is 636.795454. Thanks for the help.

 

[AVB]

This should be the carburetor that you looking at:

I haven't worked on this style of trimmer carburetor but if it like carburetors that have this kind problem it will probably have an internal block of the metering circuits. A good long ultrasonic cleaning may clean it. Just be carefully not to damage any of the parts or gaskets.

I did however found that most of the parts are not available any longer for this Echo/Robin engine. It appears that Robin's version of the Echo EC04 had changed the intake over to where they could use a rotary carburetor instead of the float style carburetor. These parts to convert will cost more than this old trimmer is worth.

 

[Radarguy]

That is exactly the carburetor that I am talking about. I have been able to get air through all of the metering pathways that I can see. The jets are clear. I don't have an ultrasonic cleaner and not sure if my repair shop does either. I will have to check. The only thing I was thinking of was that the float is set too low and the low speed jet is sucking air.

Thanks for the help.

Russ