Sierra replacement for Pre-Alpha water pump: base doesn't fit!!

[cheburashka]

The impeller on my Pre-Alpha outdrive had two bent blades and some cracking, so I replaced it. I decided to replace the whole pump with a Sierra unit. Everything matched up, with one exception--the circular extension on the pump base is around 1mm wider in diameter than the original. I'm not sure if it was mismanufactured, or if it fits a different outdrive. It was supposed to be the right one for mine. I wound up using my original base and the impeller and upper body from the new one, but I'm a little uneasy about this. Anyone run into this before?

Thanks

 

[tommays]

Re: Sierra replacement for Pre-Alpha water pump: base doesn't fit!!

I cant tell you what fits what BUT i know there are two different pump sizes on the old units


Tommays

 

[FreeBeeTony]

Re: Sierra replacement for Pre-Alpha water pump: base doesn't fit!!

I had the same problem.......

I ended up removing the seal from the new base and installing it in the original base......it's usually the seal that needs to be replaced anyway.

 

[Bt Doctur]

Re: Sierra replacement for Pre-Alpha water pump: base doesn't fit!!

You have a base for R/MR
18-3417 should be the right one not 18-3419

 

[cheburashka]

Re: Sierra replacement for Pre-Alpha water pump: base doesn't fit!!

OK, so what I got was an 18-3320 (complete pump with base) and what I needed was an 18-3321. Any other differences aside from the part of the base that doesn't fit? Any reason the top section of a 3320 won't work with the bottom section of a 3321?

Thanks

 

[Bt Doctur]

Re: Sierra replacement for Pre-Alpha water pump: base doesn't fit!!

Anything above the base will interchange.