16HP oppossed twin valve adjustment

The 16 on my sons mower is real hard to crank over. I see all over the place that the valves need to be adjusted. What im wonder is there is a small plate held on with two screws on both cylinders just behind the intake. Is the valve adjustment behind that. This is a flat head motor and any of them i have worked on over the years did not have valve adjustments. What should the valve clearance be on that motor?
Thanks guys for the help.

Yep- behind the pushrod cover. Valve lash is not "adjustable" on L-heads. If lash is under spec, you must file it down. If there's too much lash, you're replacing parts. I will look up the spec for you later.

Slow cranking can apparently be caused by dry starter bushings, as well as the usual assortment of electrical woes like a low battery or poor connections.

From the FSM:


CHECK AND ADJUST VALVE CLEARANCE
Turn crankshaft until piston is 1/4” (6.35 mm) past Top Dead Center, compression stroke, for cylinder being checked.
See specifications below.
1. If clearance is less than specified, grind end of valve stem to obtain proper clearance.
2. If clearance is too much, replace valve or cut valve seat to obtain proper clearance. See Reface Valves and Seats,
this Section. Repeat for other cylinder.
NOTE: Always check clearances while engine is cold.

Intake- 0.004"-0.006"
Exhaust 0.007"-0.009"

Doc, if you only knew how many oppy's I could have saved knowing that bit right there... lol good bit of info!