Subject: Loss of RPM and lots of Black smoke IP: Logged
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Hi.
An interesting message board and a wealth of Diesel Knowledge. Someone maybe able to help me.
I have a problem and it is driving me crazy.
It is with a single Cyl Diesel engine in a yacht. Up to about 70-75% of max RPM all is fine. At more than than this it losses RPM back to about 50% RPM and exhausts quantities of black smoke and soot. If run at 50% power will run happy for hours. Injector has been serviced, Injector pump has been checked, OK. Engine Valve clearance's have been checked, Has been run with no air cleaner assembly with no change. In my thoughts it is definately an over fuel situation, but WHY is the question??
Any IDEAS greatly appreciated.
pat Guest
3/27/2004 08:37:09
RE: Loss of RPM and lots of Black smoke IP: Logged
Message:
you should check the return lines from the fuel pump if it,s got a distributer type of pump and the return line from the head if it is a unit injector type. the fuel line looks good but if the rubber is bad inside when the motor gets reved up it can flop over a little section of rubber or rust if it,s steel and block the fuel return. this will make it smoke badly at first then lose rpm or run badly because most systems reuse some return fuel and is esentually robbing from the pump and sometimes causing cavetation at the fuel pump reducing power and even stalling some older engines.
Subject: Loss of RPM and lots of Black smoke
