I have a reman head from a 4020 404ci Diesel.  Casting number is R34850.  John Deere part number AR34689.  This head has been machined at Midwest Machine in Liberal Kansas.  He did all machine work including machining of base, exhaust and intake ports, and guides.  He also installed the new valve seats and cut to correct depth.  I installed all new valves and keepers.  Rotators are used but where checked for correct specs.  I am a Master Certified John Deere Technician.  I guarantee my work.  These heads are getting hard to come by. 

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