Join Date: Oct 2007
Thanked 6 Times in 6 Posts
Rep Power: 9
Can't keep alternator belt tight.
I have a Yanmar GM20. I tighten the alternator belt using a wrench or flat bar, to pry the alternator off the motor (and tension the belt), and cinch it with the bottom adjustment bolt. The access to this bolt is tough (of course!, but I manage to get it very tight. Then I tighten the pivot bolt on top. It seems like the belt has loosened (more than the recommended 10 Millimeters) after I run the engine. I've tried pushing on the alternator to loosen it, in case my adjustments were not tight enough, and every thing remains tight until I run the motor. Nothing is stripped. I'm not talking sloppy loose here, and the Alternator still functions. However, it is definitely looser than when I adjusted it. Any tips?