Diesel Repower Turns Old Deere Into "Super" 4020

Diesel Repower Turns Old Deere Into Super 4020 ENGINES Engines When Terry Knipper Dyersville Iowa needed a small tractor to farm a few acres of rented land he paid $1 500 for a well-used 1966 Deere 4020     Although it was a good price he and a lot of other people too wondered if the old tractor was really worth it It was in poor shape and hadn t been started in two years It had been stored inside but was covered with rust and bird droppings he says The tires were bad and the seller wasn t even sure the gas engine would turn over     With help from his brother Chris Knipper got the engine started but the clutch slipped badly after it warmed up     He managed to drive the tractor home and once he d power washed off the bird droppings it began to look like a better investment Replacing the clutch and bearings in the front wheels and all four tires actually made it useable Unfortunately the old engine had only about a year left in it      I was headed out one day to cultivate corn and it dropped a valve he says After calculating the cost of rebuilding the engine at about $3 000 Knipper went looking through salvage yards for a diesel to replace it He couldn t find a 4020 diesel engine that didn t need work but did turn up a turbocharged 30 Series Deere diesel out of a æ70 s vintage 6600 Deere combine It s the same engine used in the 4430 tractor he explains     He traded his old gas engine and $2 000 for the diesel which had only 3 200 original hours on it That included the air cleaner and a diesel flywheel for a 4020 which is weighted differently than a 4020 gas flywheel     When he got it home the diesel engine was the right width for the 4020 frame and the engine mounts matched nicely with the holes in the frame However it was about 2 in too long I could have fit it in there by shaving the fan blades but that would have made the cooling system less efficient he says Concerned that might lead to problems especially on a turbocharged diesel he decided to cut the frame and add 2 in of steel to it He had to travel 200 miles to find a length of matching channel iron for the frame     Extending the frame meant the hood didn t fit right so he had that extended and painted at a local body shop     As the project progressed Knipper discovered the stock Deere turbocharger wouldn t fit under the 4020 s hood He located an M&W after-market turbocharger that fit the engine and the space under the hood     Besides extending the hood and frame the only other modification was to the flywheel which he had to alter slightly in order to use with the original transmission I needed the 4020 flywheel because it matched up with the transmission The center hole in the flywheel was 005 in smaller than the shaft in the diesel engine so we had someone machine that to fit the shaft Also the 4020 flywheel bolted on with 4 bolts but the engine needed a flywheel with 6 bolts so I had the machine shop make that change too     Rebuilding the tractor was a winter project done while working for his father Don on the family dairy farm and farming on his own as well     While he had the tractor torn down he replaced the water pump on the diesel engine and all the electrical wiring He also replaced all the gauges After seeing how it looked with the repainted hood he decided the entire tractor needed a paint job After painting it in the farm shop he finished it off with new decals all around including ones that proclaim his tractor is now a 4020 Diesel     Knipper says the diesel engine may be putting out close to 140 or 150 hp That compares with 90 to 95 hp from the 4020 s original gas engine     He figures he spent more than 100 hours reworking the 4020 With his original $1 500 purchase price the new clutch and tires the engine wiring paint and a recently added wide front end he has about $9 000 invested in it He figures that s still quite a bit less than a similarly powered used tractor in such good condition     Contact: FARM SHOW Followup Terry Knipper 3040 172nd St Dyersville Iowa 52040 ph 563-875-7605

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