Hi guys, ive got an ISM Cummins engine in a Sterling, and lately ive noticed that its real slow to fire up.
It seems to happen at random, and when cold its takes a lot of cranking to get it to start, (too much) and then when it starts it seems to fire up on not all cylinders, then after a second or two all the rest of the cylinders fire.
When the engine is warm during the day, it seems to start quicker, but still not as fast as my Cat's or Detroits.
My gut feeling is either the fuel non return valve, or the crank position sensor ?
A few years ago, I had a similar problem on a M11, and they told me that apparently the crank position sensors have 2 loops, and that when one fails it will run on the redundant loop, but it takes longer to start. Sounds good in theory, but could it be this ?
Or is it more likely to be the fuel non return valve, and if so, where is this ? on the pump or near the pump ?