The throttle would only accelerate and freeze solid when trying to decel. Disassembled the govenor bell housing and replaced all parts except for the bracket that mounts to the dozer. After reinstall the throttle is locked solid. With the linkages removed the control rod rotates as a unit freely and all linkages move freely. I did have to tap the control rod into the bell housing to assemble. What did I do wrong? Or do I need to be looking somewhere else? I reassembled exactly as it looked before disassembling the old unit.
I realize you are new here but if you expect any response you need to supply model and serial numbers. There are 23 models of D6C's
Grey Iron.....76' model d6c 90b1703
What is the engine s/n? My book shows a 3306 (44V) series. Is that correct? What type of fuel injection pump? Scroll or sleeve metering? Is the Decelerator control on the bell crank shaft or is it the dashpot type? If it's on the bell crank it will be the two roller and two spring type and has nothing to do with the governor except for the arm connection. Probably going to take a picture to identify what you have.
Not sure on the series of the 3306.....I'll look tomorrow There are two rollers and three springs inside the bellcrank. Sleeve metering pump.
OK, appears you have the early style decelerator control with the sleeve metering pump. Correct, two springs and two rollers with a third locating spring. Did you inspect the inside of the cover assy.? If the roller ramps are excessively worn the assembly should be replaced. Should not be any flat spots on the rollers. The assembly, rollers, springs and cover with ramps act as a roller clutch and must be free working to function properly. Should use just a light oil when assembling the parts (some work better dry). You can use a small dab of grease to hold the roller springs in place for assembly. If the unit is not functioning properly the clutch function will either not work or lock up. It is a temperamental arrangement at best so everything has to be right.
Everything internally and bellcrank cover was replaced........was tight when assembled and I coated in dry silicone. Is there a "trick" to proper assembly? I had to tap everything together on a vice.
Assembly should be slip fit where both parts of the shaft rotate freely. Sounds like the bushing in the cover is to tight. No tricks required. The low idle stop on the bellcrank needs to be in the vertical position when contacting the adjusting screw (approximately 0.25" of adjusting screw protrusion.
How do I "loosen" the bellcrank? Sand with emery? The inner shaft (to hand control) has plenty of room and moves freely.
Usual process would be to ream the bushing to fit the shaft with 0.001 - 0.002 inch clearance. Remove seal (probably will get destroyed unless you can press the bushing out with the seal without damage). Re-install bushing if you remove and ream to size. Press in new seal or use the old if it can be salvaged.