[dockterj]

I've checked both the JD 317 service manual and the KT17 manual from Kohler and only the Kohler manual specifies "Rotate camshaft to position where cam has no effect on tappets." I've noticed on my engine that TDC on the compression stroke appears to have the most clearance. At other camshaft positions there appears to be about .005 difference. Is this normal? Is TDC the correct position to set clearance or should I position the cam somewhere before the valve opens?

 

[jdalchemist]

Jacob,
At "TDC" the valves will be fully closed for one cylinder. Rocking the flywheel a few degrees will have no effect on the valve closure on this cylinder. Set the valve lash on these valves by grinding the valve stems (grind them flat), as needed. Now rotate the flywheel 360 degrees to TDC and set the valve lash on the other cylinder. Things work this way because the pistons are out of phase (with respect to power and exhaust strokes) and the crankshaft turns faster than the camshaft.
Harold

 

[dockterj]

Harold,
Thanks for your response. I'm having a terrible time with this seemingly simple task. I've just about had it with this engine! I thought I had everything adjusted correctly and was getting perfect clearance numbers that were repeatable (.006 intake, .014 exhaust). Then I put the springs in and luckily re-measured. All of the clearances had decreased by around .003!!! I guess I wasn't pushing the valves in hard enough when I was grinding and checking. Oh well, at least this is fixable without getting new valves!

But the latest "issue" - the Kohler book is very clear about the valve clearances (.003-.006 intake .011-.014 exhaust). I made the "mistake" of looking in Deere's 317 book and it has the intake clearance as .008-.011! This is for both series I and II. It is listed like that in multiple locations.

Now I don't know what to do!

Also, Am I wrong to be targeting the high end of the spec or should I try to get in the middle instead?

Honestly, I usually don't have these kinds of problems but for some reason this task is just beating me up.

 

[jdalchemist]

Jacob,
The valve lash spec is not the only difference between the Kohler and Deere manuals. Maybe the Deere engineers learned something and adjusted accordingly. For what it is worth, Kohler continued the intake spec for the Magnum engines. I favor the upper end of the valve lash range to give some room for valve face erosion. This means 0.006" for the intake valves, but I expect the Deere spec would be fine as well--at worse a little bit of clatter.
Harold