I am looking to do a little fuel pump work to a early to mid 90's 772 BH if its not huge pain in the ass. Was wondering if anybody could point me in a direction for some info or if anybody had any pointers? I haven't had any luck with your run of the mill Google searches. Im in no way familiar with JD pumps but im pretty slick with a cummins...... i noticed a solinoid on the right side of the motor that appeared to control the aneroid in some way. Boost limiter maybe? What happens if i tinker with that? Any other tricks i could do to gain a little HP that won't require a pyro or excessive tire spin? Also be advised that this is a public owned machine as i work for the county road department so most ch anges need to be fairly "covert"!
Look at the injector pump If it is like most of the bigger JD engines from that era I have had anything to do with it will have a Bosch or similar piston pump. There should be slotted screw with a jam nut on the back end of the pump. I think if you turn it clockwise 1 full turn you will gain about 35-40 hp assuming nothing is wrong with the rest of the fuel system or turbo. The fuel burn should go up quite a bit and it will probably blow a little black smoke. Oh and of course your warranty will be void. Ha. Personally I probably wouldn't turn it up unless it is a real dog. The additional fuel burn may not be worth the gain in HP. The ones we used to turn up were in the 80's and fuel was less than a buck so it really didn't matter too much. Good luck! I like your grader. Wish I had a 772BH. Tried to find one but ended up with a Fiat Allis FG85 AWD. Cummins engine is great. The machine is like new with only 3800 hrs and is probably as good as any machine out there. However, I am partial to JD.
I don't know why you would want to 'turn it up'... those year 772 blades had plenty of power. The issue I had was only having half as many reverse as forward gears and a rocker switch for the rippers. Overall they were a good machine in my opinion.