Question About Impeller face seal and impellor blade postions?

[JWebber]

I pulled my drive this weekend to do alignment and replace my impellor, Alpha one gen II drive etc... When I split the lower from upper, I noticed that the face seal on top of my impellor housing was not there. Now the new kit I have has it in the kit. So did mercruiser make a change at some point adding this seal as a service bullitin?? Also the blades of the impellor werefacing in the right direction but two were facing opposite direction. I'm not sure if the manu's place it wrong, but I would guess that if spinning in one direction would make them face the same way. Or do worn impellors do this? It looked pretty good condition after three summer seasons in lake water with 193.2 hours on the complete system. See pic!

 

[Don S]

Re: Question About Impeller face seal and impellor blade postions?

I noticed that the face seal on top of my impellor housing was not there.

Yeah, sometimes they fail due to age, or maybe even getting hot from the exhaust. They are supposed to still have them.

On Gen II drives, the impeller must be installed in the proper direction, because they do not always flip over the right direction on that type impeller.
Why a couple of them are backwards who knows, perhaps the installer of the drive the last time turned the shaft backwards and a couple of the blades turned around, or maybe the impeller was installed wrong (and whoever did it forgot to install the face seal too)

No one can tell you why your impeller has a vane or two backward or why the face seal was missing.
What you need to do is install it per the manual.

PS, your pictures do not need to be that big and close up to see a couple of vanes backwards.

 

[JWebber]

Re: Question About Impeller face seal and impellor blade postions?

I see! Yea made me wonder! Oh well! all is well now and its pumping water alot better now, plus my riser is alot cooler too. As far as the pics I have no control over those unless I spend some money on software to down size, but that's what you get from a iphone. LOL! Thanks for the responce Don S.!

 

[Don S]

Re: Question About Impeller face seal and impellor blade postions?

You can resize pictures on about any software for a scanner or digital camera anymore. Or, you can host your pictures at one of hundreds of free sites and resize for free.