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| From a couple books in my library about the design of the new generation tractors:
JD official word until the unveiling of the 4 and 6 cylinder tractors in Dallas was "two cylinders forever."
The books show a V4 both crosswise and longitudinal mockups. The longitudinal was wider than corn rows.
They picked the envelope of the 720 as the desirable package size for the higher power tractor.
They built a huge supply of two cylinder tractors before shutting down Waterloo for reconstruction. during that design time (about 4 years) engineers worked in secret locations to do the designs and they knew the factory machinery for making 2 cylinder engines was worn out and had to be replaced, which gave them extra design freedom. I think the factory picked out inflexible equipment so that the cylinder spacings stayed the same as the 4010 for 20 or 30 years because the block boring machines weren't made to be adjusted. And so even though the gas and LP engines had fewer main bearings and could have been shorter engines, they have the same length block as a diesel with 7 main bearings to use the same block boring machines. Those long intake manifolds make it hard to really tune a 4020 gas engine and to get decent fuel economy.
If you let me pick the soil and the width of the bottoms, my 4020 will pull 8 bottoms, but in my ground 3x18 is plenty. I didn't run out of torque, just couldn't keep the front wheels near the ground. And that early tractor with 15" tires woudn't have had the traction of the 18.4s that were options. My 4020 owner's manual shows 13.6 though 20.8 plus something really wide were factory options. 13.6 had to be duals to hold up the weight. Buying one with 15.5 tires probably cost less than the new 18.4s. Probably wasn't the best place to save money.
Gerald J> | |
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A Look Back < < < John Deere 4010 Production
