hugh warner
New member
I have a John Deere 6081AFM75 M4 marine diesel with a variable pitch propeller. I constantly have high EGT problems (maxing st 439degrees celsius, which is its max temp) when I put the engine under load. My solution has been to run at high revs and low load, to keep the temp down. I have replaced the injectors, redone the fuel timing, replaced the air intake filter, removed and cleaned the air intake manifold and cooler, removed and cleaned the exhaust manifold, reconditioned the S300W turbo, replaced the 5" dry exhaust with a 6" dry exhaust and added a boost pressure gauge which confirm no turbo boost pressure at RPMs under 1,800 and still not massive boost at max 2,400RPM. Nothing fixed the problem. I had John Deere out twice to try and solve the problem. All I got were bills and no solutions. They said replaced the turbo with another reconditions S300W - what would that make a difference. So I took the advice of my sons and I replaced the S300W turbo with the smaller S2BW turbo. Problem was solved immediately. Boost pressure at low RPM, can load engine right up, EGT is 100degrees lower in temp. Fuel consumption is where it should be. SO, John Deere have been completely and utterly useless. I wonder if the original fuel map is wrong and doesnt match with the M rating. Has anyone had a similar issue. JD again, are completely useless, they simply will not give me any data to work with or verify. Keen to get thoughts.