DID I BUY THE WRONG IMPELLER???

[TkdSilat]

hello all
the engine is a 69 mercury 200 20hp s/n 2250249 i initially ordered the sierra impeller but then i found the mercury part. the mercury part seems too big and i CANT get it to fit the sierra part lines up perfect and installs nicely. The old impeller is just as big as the mercury one I ordered but i Cant get it to fit for the life of me. any tips??? see the pics... the shaft has the sierra part installed... can I use this one, or will it damage anything??

thanks for the help!

 

[wrench 3]

The Sierra impeller is definitely the wrong part. Way too small.
The manual tells you to lube everything up with petroleum jelly, place the impeller on the shaft and press the water pump cover down over the impeller while rotating the shaft clockwise.
However, I prefer to lube with silicone grease and install the impeller into the cover first, turning it counter clockwise being careful not to damage it on the sharp edge of the insert.

 

[racerone]

The impeller in the middle picture is for a newer model 20 hp.

 

[minuteman62-64]

The Sierra impeller is definitely the wrong part. Way too small.
The manual tells you to lube everything up with petroleum jelly, place the impeller on the shaft and press the water pump cover down over the impeller while rotating the shaft clockwise.
However, I prefer to lube with silicone grease and install the impeller into the cover first, turning it counter clockwise being careful not to damage it on the sharp edge of the insert.

Last year I purchased an OEM impeller for my Mariner, which failed right out of the box. Followed with Sierra impeller. Sierra impeller was slightly smaller than OEM - but didn't look like as much difference as you show. However, it worked w/no problem - and wore out from age, not an out of box failure.

Second on the installation technique. When I do it by the book the impeller tends to slide the gasket around and sometimes ends up out of position.

 

[merc850]

According to this site http://store.oldmercs.com/category_s/856.htm it's a 1967; going by your serial Nr.

 

[MTboatguy]

Yup, that is a 1967 model 200