Hi to everybody.
I'm new here and I wonder if anyone can help with this problem, please?
My 1990 Atco ride on (Briggs&stratton 12hp 281707 side valve) was given to me as a non starter. The ignition module was faulty and replaced. So far so good. It was starting but when I activate the cutter deck it would stall. This was because the revs were not high enough on max. Main jet on carb was badly scored and the throttle plate had a ton of play so the carb was replaced with a new one. This was after I noticed that on every compression stroke fuel and air was being pushed out of the carb. The engine inlet valve was not closing properly at a quarter inch passed tdc. Unfortunately I took too much off the valve stem and the minimum gap I've got is 15 thou. Both valves lapped in, by the way.
Due to what I think is pre ignition the damn thing now backfires very loudly and snatches back the rope big style; I'm using the rope now because the starter plastic cog has stripped because of the problem.
So, I was confident that the flywheel key had broken, but it's in perfect shape.
I now haven't got a clue what to do. I don't want to give up but I'm getting close.
'Unfortunately I took too much off the valve stem and the minimum gap I've got is 15 thou.'
There is your problem. The compression release is not working, replace the valve.
Many thanks guys for your help. I think a new inlet valve is the way to go for me. That'll teach me to be too heavy handed with the file. That's a mistake that won't happen again.
