Impeller replacement

[Set2sea]

I am planning of replacing my Oberdorfer impeller tonight.
I searched the tech wiki, Main Sheet and with the search function down, I can't find what I am sure is there.
Question: Should I pull the shaft and impeller out of the housing to replace impeller or should I pull off the retaining ring while inside the housing and then pull impeller. I am figuring that you could do it either way but just wanted to double check.
Thanks
Paul B

[Stu Jackson]

Pull the whole shaft.  When the search comes back up, I'll link you to why this is possible (it's in the Oberdorfer Rebuild thread, with pictures).

Actually, it's in the tech wiki, no search needed:  http://c34.org/bbs/index.php/topic,6766.0.html

[Set2sea]

Thanks Stu, I saw the rebuild of the tech wiki but I didn't see anywhere about just changing impeller.
I will pull the shaft out.

[Ron Hill]

Set2 : The next time you need to replace or just inspect the impeller on an Oberdoffer; just pull out the impeller if you have already removed the "C" clip/ snap ring that holds the impeller on to the shaft.

Why they ever install that "C" clip is beyond me?  The impeller can't go anywhere and it's easy enough to pull the shaft if you want to inspect it.  In an emergency/faster job it sure is much easier to pop off the impeller if you don't have to screw around with that "C" clip.

A thought

[Stu Jackson]

Ron's right.  That's one way.  What I do is install a new impeller on a new shaft, so when I change them out I know that the new impeller is the one on the backup shaft.

[Set2sea]

OMG what a PIA it is to get that retaining ring off of the shaft, Probably even harder to get it back on. I see why you say to have an impeller on a shaft set to go.

[Kevin Henderson]

Stu... Great idea to get a spare shaft to keep an impeller on at the ready.  What is a good source to order that particular part? 

Set... The last time I changes out my impeller I fought and fought.... and fought to put that retainer ring back on.  But after seeing the many posts that said it really serves no purpose and is an overengineered item, I simply never installed it again.  No problems since then either. 

[Stu Jackson]

Kevin, we've been suggesting DEPCO for pumps for a loooong time.

The retainer ring:  back, as Ron says, BI, before internet, I didn't even know there was something called a restrainer tool (or something close).  So when I first did this in maybe 1999, I got two small flat head screwdrivers - really small - and managed to pry it off without breaking it.  Putting it back on simply consists of slipping one side into the slot and pushing down with the screwdriver blade.  I never found this to be too hard, and never bought the tool.  There is a tool out there, though.  Someone might actually know the proper name for it so you can buy one, but I'd save my $$ up for new sails, and buy a couple of small screwdrivers - not as small as jeweler's drivers, but just small ones.

[steve stoneback]

They are simply called "snap ring pliars".  They make them for inside rings and outside rings and they make different sizes of them.  Obviously for this task you need small ones for outside rings.

[John Fogelgren]

Can you pull the shaft with the impeller on the Sherwood as well?

[Stu Jackson]

Yes, the inside of the engine and the shafts are the same.  IIRC, the Oberdorfer rebuild thread has pictures of the shaft and the engine guts.

Your M25XP (right?) will not have had the issue of "the older engines where you can't."

[Ron Hill]

John : You can not pull the shaft out with the impeller on a 908 model Sherwood, not too sure on a 903 model?