Deal on Poulan tractor mower needs valve lash adjusted

I got my hands on a 2005 Poulan tractor mower with a B&S 17.5 hp engine. I don't have the motor number now but I believe it needs valve lash adjusted because it stops at TDC as compression release seems not to work. Poulan was of little help and even when giving me the part number for the cam it was incorrect.

All I need is to figure out where to get a service manual for the specs on the lash, as I believe the compression release is just a bump on the lobe and is a yearly maintenance procedure.

The valve clearance is .004-.006. The compression release on the camshaft is a weight activated half-moon rod that moves the intake valve off its seats. it has a spring to return it to its resting postion when not running.

Sometimes the spring breaks, sometimes the weight breaks. I have seen compression release issues were they have to be adjusted once in the life of the mower, and I have others that I have to adjust every 6 months.

Thanks, I actually contacted Briggs and Stratton, they are sending me a service manual, should be here anytime, this way I have all of the info on hand for any issues with the engine.