does merc impeller work better than original?

[fishkiller]

when merc bought out the force/us marine etc, why did the merc impeller replacements change the number of fins on some of the impellers? the original chrysler and replacement sierra impellers for a 83 75hp outboard had 12 fins and now the merc replacement has only 6. do the old motors have less overheating problems with the new impeller(6 fins) or was this impeller one that merc already had and it just happened to fit the old chryslers?

 

[eurolarva]

Re: does merc impeller work better than original?

The 3065 impeller has six blades and the 3085 has 12 blades. These are after market impellers and both will work. Mercs website shows a lot of motors still using the 12 blade impeller. The part number is 47-F84065. Attached is a link showing a picture of the impeller by part number Impeller picture