Small Engines (Lawn Mowers, etc.): blade adaptor, bolt and nuts, spring retainer

Question
Hi John, Thanks for your suggestion on removing blade adaptor. I applied heat to it, but when doing so, my neighbor saw that it had a key way. We did'nt know how to remove key so we just worked with the dust cover and eventually got the belt off. I have a new question, new belt is on and spring and spring retainer replaced. Is there a way to tighten belt tension? Mower has sluggish pull when on the grass.  I replaced spring retainer with a long bolt and nuts to had tension on the pulley on top of the motor, but too much tension causes belt to slip off when engaged. My craftsman is model # 917.378070. Thanks in advance for any suggestions you may have.

Answer
Was the new spring and retainer different than the old one?
I noticed a lot of parts changing, so they may have done a lot
"improving".
One thing I have noticed about working on these self propelled
units, that you need to dig out all of the old caked in grass
out of the "v" of both pullies, or you will have trouble.

Otherwise, I do not know of a way to add more tension other than
the factory spring setup.
Hope this helps