Tchamp
Silver Member
Does anyone know where the redline is on the ym 1500 diesel engine?
Does anyone know where the redline is on the YM1500 diesel engine?
In the YM1500 Parts Manual, the specification sheet on page-3 shows 2,400rpms. There is usually a safety percentage of 200rpms on engines as the gauges are not 100% dead-on. Are you setting the throttle limiting screw to stop right at the top limit?
In the YM1500 Parts Manual, the specification sheet on page-3 shows 2,400rpms. There is usually a safety percentage of 200rpms on engines as the gauges are not 100% dead-on. Are you setting the throttle limiting screw to stop right at the top limit?

I think that 15 @ 2400 is just rated Horsepower. Above that torque is diminishing, and it risks excessive wear (some stresses go up with the SQUARE of the rpm increase) and/or you are exceeding the designed cooling capacity. But I don't think 2400 is redline like you see in a car which cautions about immediate disaster.See attached, it is 2,400 rpms.
Line-8 in the chart ..
I think that 15 @ 2400 is just rated Horsepower. Above that torque is diminishing, and it risks excessive wear (some stresses go up with the SQUARE of the rpm increase) and/or you are exceeding the designed cooling capacity. But I don't think 2400 is redline like you see in a car which cautions about immediate disaster.
I saw a Ford chart like this but simpler, long ago. It has always stuck in my mind as illustrating how HP (just the mathematical product of torque x rpm) eventually falls off at high rpm because torque is falling faster than rpm is rising.I tried to explain that in a recent PTO horsepower thread. People just don't get it.![]()
I saw the T chart while looking for the one I posted. Here it is! (1922).I wish my 1925 Model T engine had curves like that. It barely squeezes out 20hp on a good day. :laughing:
Interesting that they chickened out at 1900 rpm. :laughing:Yeah, I believe I have that one. Never seen one do 50mph though. I think you'd leave parts behind.![]()
Looks like Yanmar wants you to run 2400 rpm for maximum available hp.What rpm is peak hp at .
LOL. Ford claimed they took some test engines to 3000rpm.But that was in a lab. Without that 75lb. flywheel, no doubt.
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I seldom run anywhere near maximum rpm on either tractor. The 3-cylinder YM186D occasionally, momentarily, when I'm trying to do something that I probably shouldn't.... I seldom even get the machine over 2,600rpm anyway. ... You'll like your YM1500.