1950 John Deere BN Valve Adjustment

John Deere manages to make things difficult. Even the most basic task of adjusting the valves was way more difficult than it had to be. The carburetor float bowl is in the way of getting the valve cover off, so I had to drop the bowl. The large stem poking down in the photo is what the bowl nut threads onto. That stem is still in the way to get the valve cover out all the way but there was just barely enough room to do the job. I suppose since the carburetor on this tractor is not the correct one, it just might have been easier if the right carb was in place, but I doubt it. Most of these DLTX carburetors are very similar in construction.

In order to spin the engine over by hand, I had to remove the flywheel cover. I could have bumped the starter to rotate the engine but I had to adjust the starter rod length anyway, and the cover had to come off for that project also.

The valves are set cold to 0.020", both intake and exhaust. The owners manual says to get each piston to TDC on the compression stroke, then adjust that set of valves, then repeat for the other cylinder. The book says to tighten the adjuster to zero lash, then back it off 1/3 of a turn, or use a feeler gage (.020"). The valves weren't off by much on this engine but it's nice to know they are set right now.