Catalina 34

General Activities => Main Message Board => Topic started by: TortolaTim on August 02, 2019, 01:19:49 PM

Title: Which Oberdorfer pump is this?
Post by: TortolaTim on August 02, 2019, 01:19:49 PM
My Oberdorfer has a slow drip and I want to replace the gasket and impeller, but can't find the model number on it. There is a small 8920 on the side of the housing, but I don't think that is the model, as I've been searching around online. Boat is a 1989 with the M25XP.
Title: Re: Which Oberdorfer pump is this?
Post by: Stu Jackson on August 02, 2019, 02:09:54 PM
Most likely the ubiquitous 202M-15.  Paper gasket against the engine and at the faceplate.  There are newer models that replace the paper gaskets with O rings.

www.depcopump.com
Title: Re: Which Oberdorfer pump is this?
Post by: KWKloeber on August 02, 2019, 04:17:28 PM
Tim

8920 is the part no of the body on the old series (202M-15) pump.  The newer N202M-15 body is 8920-1.

You want gasket #6599 and impeller #6593 (same p/n for all the 202-xx pumps.)
Check the backside of the cover with a metal straight.edge.  The impeller wears an indent, which can affect suction/flow.  The heavy bronze covers CAN be resurfaced.

Maybe TMI, but all the new N202 pumps seal w/ an o-ring on the pump body.  Don Moyer sells an aftermarket cover for the old gasketed pumps that has an o-ring set into the pump COVER (and it has captive thumbscrews to boot.)  Pretty slick item.
Title: Re: Which Oberdorfer pump is this?
Post by: Stu Jackson on August 02, 2019, 04:29:54 PM
Quote from: KWKloeber on August 02, 2019, 04:17:28 PM

Check the backside of the cover with a metal straight.edge.  The impeller wears an indent, which can affect suction/flow.  The heavy bronze covers CAN be resurfaced.


Good point, but they don't need to be "resurfaced," unless I misunderstood, just fine sandpaper the surface.  I've had the same pump faceplate for more than 15 years and two seal rebuilds.  They do last a long time.
Title: Re: Which Oberdorfer pump is this?
Post by: TortolaTim on August 02, 2019, 06:25:53 PM
Thanks for the info guys. I bought a couple new impellers today, and will take a look at the o-ring covers. I appreciate all the great stuff on this site, I've learned a ton already!
Title: Re: Which Oberdorfer pump is this?
Post by: KWKloeber on August 02, 2019, 06:53:17 PM
Quote from: Stu Jackson on August 02, 2019, 04:29:54 PM

"resurfaced," unless I misunderstood, just fine sandpaper the surface. 


If it's deposits or fine scratching, yep.  It's not that often but if it gets cupped or a recess in them (or very deep grooves) where the impeller runs then you need to remove material all around the cup or recess and leave a perfectly flat (not just smooth) suirface.  It can be done on a perfectly flat surface (like a pane of glass) using very thin wet n dry or crocus cloth, or even a wide sharpening stone, but need to make sure it's even pressure, etc., etc. 
Title: Re: Which Oberdorfer pump is this?
Post by: Ron Hill on August 03, 2019, 12:47:57 PM
Guys : I used to take my old Oberdoffer face plates to a machine shop and a friend would "reface" them for $5!!

If you decide to go the "sandpaper" route as Stu suggested  1. Make sure you have an absolutely flat surface to put the plate on and flat block to wrap the paper around &  2. start with 400 grit wet/dry paper (WET) and finish it off with 1500 grit WET paper!!!

A thought
Title: Re: Which Oberdorfer pump is this?
Post by: lazybone on August 03, 2019, 02:13:57 PM
You can make a gaskets out of notebook paper.  Make a dozen... last you the rest of your life.
Title: Re: Which Oberdorfer pump is this?
Post by: Stu Jackson on August 03, 2019, 08:12:59 PM
Quote from: Ron Hill on August 03, 2019, 12:47:57 PM
Guys : I used to take my old Oberdoffer face plates to a machine shop and a friend would "reface" them for $5!!

If you decide to go the "sandpaper" route as Stu suggested  1. Make sure you have an absolutely flat surface to put the plate on and flat block to wrap the paper around &  2. start with 400 grit wet/dry paper (WET) and finish it off with 1500 grit WET paper!!!

A thought

I grab whatever sandpaper I can reach in my toolbox, find the finest I can, and put it on a block of wood and rub away.  DRY. 

As long as, as Ken K said, there isn't a huge divot in the faceplate, it's been working for me for 21 years.

If there was a deep gouge, I'd buy a new faceplate.  That's harder to do here on Vancouver Island than it was in SF where I could go to the local Universal dealer on the way home between the boat and home.

BUT...I found one or two here, so if I need one I can get one.

As they say here on "The Island," "I can get it for you by Tuesday from Vancouver!"
Title: Re: Which Oberdorfer pump is this?
Post by: Ed Shankle on August 04, 2019, 05:35:47 PM
I use Scotchbrite pads. Seems to work good. Any concerns with that?
Regards,
Ed
Title: Re: Which Oberdorfer pump is this?
Post by: KWKloeber on August 04, 2019, 06:57:22 PM
Ed

On a scale of 1 to 5, it's probably a 4 (for removing just gunk, not resurfacing a divot or belly.)  Better would be rubbing the cover across a flat surface w/ wet n dry, but is it 3M fatal? Nah.
Title: Re: Which Oberdorfer pump is this?
Post by: Ron Hill on August 05, 2019, 02:01:44 PM
Guys : You can take the wear marking off the faceplate any way you want!!

The technique all depends on how smooth a product you have when you are finished!  I liked mine very SMOOTH!

A thought