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Re: excavator hard start

thank you very much comments    were very helpful only issue now is figuring out which hose is sucking air

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Re: excavator hard start

All I can say for certain is that anything that gets to the injectors has to pass thru the fuel injection pump.If the orifices in injectors do get plugged, the result is damage to injector tips or major damage to the fuel injection pump because of hydraulic lock. Plugged fuel injector orifices are not usually repairable, the spray holes are very small, typically .006" diameter.

I am a former diesel fuel injection shop owner and have over 40 years of experience in the heavy duty mechanic trade..I humbly submit that either a basic troubleshooting step has been overlooked or else there is a language barrier to this issue.

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Re: excavator hard start

the injectors had a black substance over it that had to be cleaned before it started again , but the stuff accumulated gaain by the time the engine was turned off n wud not restart unless cleaned again

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Re: excavator hard start

I don't know what the steps were used to conclude that injectors were clogged. Might I just suggest that injectors do not "clog" and that the problem is likely a fuel supply to the fuel injection pump issue. I think that during the process of cleaning the injectors, the system was purged of air and the engine started and ran ok. Most mechanical fuel systems will tolerate some air entrained in the fuel but when the engine stops, the air rises to the top of the system, usually the fuel injection pump. Injection pumps do not pump air very well and hard starting is the result.

  Before "cleaning" injectors again, start the engine, doing whatever it takes to make it start, then subsitute the fuel return hose to one that can have the open end submrged in a pail of fuel. with the engine running, watch the open end of the return hose to #1 see if you have a return flow and #2 is the return flow clear of air or are there air bubbles present. If there are air bubbles, then you may need to substitute the supply hose and run the engine from a different fuel source such as another pail or tank. If the engine will run ok with the substitute supply then you need to check/replace the original fuel supply hose and/or fittings as required.

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excavator hard start

hi gooday i could really use your help i have a 320dl  6.6 engine caterpillar excavator i was having a probblem where it only started wit quick start , i borugh in a machanic who said the injectors were the problem we change all injectors long with filters , we flushed all the lines.The excavator worked uptimum for about four hours the following day , we shut off the excavator and finished for the day the following day upon trying to start the excavator we had hard start once again , the mechanic checked the pump it is fine , he cheched the injectors n they were already clogged he cleaned them and the machine worked fine , but when we shut off the engine to restart again we had to clean the injectors , it wont start without we clean the injectors which somehow are clogging quite quickly , could you please give me some suggestions