Hello, the engine belt on my 4.3 Merc 220 HP came loose. Would it be just a matter of tightening the belt tensioner to put it back in place? Would it mess up the timing? Thanks for the info.
Check that all the pulleys are on the same plane. You can't tighten the tensioner unless it is falling off the engine. That belt has nothing to do with the timing..
The tensioner is not like a automotive one that is sprung. Just loosen off the tensioner nut (5/8' spanner), refit the belt and adjust the centre bolt of the tensioner mounting with a 5/16" spanner, then (while holding the 5/16" spanner in the right place) tighten the 5/8" locking nut. The right tension is when the longest run on the belt (for a standard cooling Alpha engine that will be the alternator to water pump) deflects 1/4" with moderate thumb pressure (that's what the book says :facepalm or the correct tension if using a Belt Tension Gauge....
or the correct tension if using a Belt Tension Gauge....
