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Cat 303cr mini excavator troubleshoot

I have a cat 303 cr mini ex and under hydraulic load it's trying to stall the engine? Any suggestions...hydraulic pump going out??maybe??

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Posted on Jan 02, 2017

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SOURCE: 330 excavator with a c9 cat engine, heavy SMOKE

At the time you made all the above repairs, did you replace the "throw away" turbo charger? The turbo charger commonly sucks oil, and it is not repairable.

Run it without the inner & outer air cleaner. If it isn't the turbo, run the injector cut out test. If the injectors are ok, then you need to replace the injection system hydraulic pump, which is also unrepairable.

Posted on Apr 23, 2010

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SOURCE: Ex-Cell EXPRO2530 w/Cat Pump. Pressure builds and stalls engine.

Your unloader valve is not wotking, get a diagram of the pump from cat and it will show what parts you need to replace, or check for blockage in the valve.

Posted on Jan 10, 2011

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The 121-3 is a Kubota number.
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