Catalina 34    Message and Discussion


[C34 Home] [C34Tech Notes] [C34 Tech Wiki] [C34 Cruising Wiki] [Store] [Join C34IA]

Please login or register.

Login with username, password and session length
Advanced search  

News:

Take advantage of the new theme, update your forum profile.

Pages: [1]   Go Down

Author Topic: Mysteries of the Oberdorfer - Seal Replacement - REBUILDING A PUMP w/Flix  (Read 10732 times)

0 Members and 2 Guests are viewing this topic.

Clay Greene

  • Forum - Chief Petty Officer
  • ******
  • Karma: 6
  • Posts: 519
    • View Profile

So, I managed to get the old seals out and now am looking at getting the new seals in.  Looks like a very tight fit (not surprisingly, given that it is a seal).  Any trick to doing so without damaging them in the process other than a good coating of oil and an attempt to apply even pressure?  Thanks.  

[added Seal Replacement & w/Flix to title - Stu  1/19/12]
« Last Edit: March 26, 2012, 09:30:02 AM by Stu Jackson »
Logged
1989, Hull #873, "Serendipity," M25XP, Milwaukee, Wisconsin

Ken Juul

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 12
  • Posts: 2077
    • View Profile
Re: Mysteries of the Oberdorfer
« Reply #1 on: January 19, 2012, 09:15:01 AM »

The key is even pressure all the way around the seal.  Set the seal in the bore, using a piece of wood bigger than the seal as a "punch" tap it in with a hammer.  Once it is flush with the case, if it needs to go in further, use a socket or piece of pipe that just fits into the bore to finish the job.  You want the pressure to be near the outside edge of the seal not the center so you don't dish the seal which might make it less effective.
Logged
Ken & Vicki Juul
Luna Loca #1090
Chesapeake Bay
Past Commodore C34IA

Clay Greene

  • Forum - Chief Petty Officer
  • ******
  • Karma: 6
  • Posts: 519
    • View Profile
Re: Mysteries of the Oberdorfer
« Reply #2 on: January 19, 2012, 10:35:37 AM »

Many thanks, Ken.  I'll give it a go. 
Logged
1989, Hull #873, "Serendipity," M25XP, Milwaukee, Wisconsin

Ron Hill

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 47
  • Posts: 5732
    • View Profile
Re: Mysteries of the Oberdorfer
« Reply #3 on: January 19, 2012, 02:47:19 PM »

Clay : I've written a couple of Mainsheet articles on your very question.

Anyway, take some grease and coat it on the inside of the pump.  Then make sure that the seal is set in correctly (I believe that the writing goes toward the center = weep holes). Then take a deep well socket just slightly smaller than the inside of the pump and start pressing or tapping it in.  The first seal is the oil seal so it goes in first and just past the weep holes and as Ken said make sure it's even and not cocked.
Then take the water seal and do the same, stopping just before the weep holes (again make sure the seal is not backwards).

Hope this helps. 
Logged
Ron, Apache #788

Tom Soko

  • Forum - Petty Officer 2nd Class
  • ****
  • Karma: 1
  • Posts: 167
    • View Profile
Re: Mysteries of the Oberdorfer - Seal Replacement
« Reply #4 on: March 25, 2012, 10:31:05 AM »

Clay,
Rather than using a hammer to tap in the seals, you might try using a bench vice.  You can apply even, controlled pressure.  Using a socket as others have mentioned will allow you to precisely position the seal where you want it.
Logged
Tom Soko

Stu Jackson

  • C34IA - Secretary
  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 59
  • Posts: 6059
    • View Profile
Re: Mysteries of the Oberdorfer - Seal Replacement - REBUILDING A PUMP
« Reply #5 on: March 25, 2012, 09:02:34 PM »

Thanks to you, Ron Hill and his May 2002 rebuild article, the Sailnet discussion, and a fine Sunday afternoon.

In 1999, when our new-to-us boat's raw water pump started leaking, I went to the local Universal dealer, who said: "It'll cost more to rebuild your pump than to buy a new one."

Being A NEWBIE, I did.  Actually, it was a pretty neat deal:  $176 + tax in 1999 $$s, and all it took was four nuts on the studs to remove the pump and replace it.

Recently, I've seen evidence of leaks (see the Critical Upgrades sticky topic for "checking your engine").

Time for a costly new pump?  

Wait!!!  I'd read about rebuilding a pump.  I read Ron's Tech Notes article, and then literally stumbled across the linked Sailnet discussion.

I bought the Allen wrench, and with the help of a neighbor's grinder, cut it down and got to work.

It was SCARY at first, whacking the pump's innards, but once I realized that the pump is like a tank and the seals are simple replacement parts that can get knocked out, removed and replaced, it became much easier.

Using a pair of needle nosed vice grips makes holding the wrench pretty easy, if not necessary.

The idea from Sailnet about the 12P nail worked, too, 'cuz the Ron Hill tool may be too thick to get between the carbon bushing and the water seal.

Sweet feeling when the old ones came out.

Easy to get the new ones back in with a piece of wood and a socket.

Another helpful link that links back here:  http://www.sailnet.com/forums/diesel-engine-forum/60992-rebuilding-oberdorfer-pump.html

This link is important because it shows the tool that Ron Hill built to get the old seals out (1/4 inch hex head Allen wrench ground down to fit).  second picture, link to Ron's article:  http://www.c34.org/mainsheet/pdf/May_2002.pdf

The C34 Tech wiki also has that article:  http://www.c34.org/wiki/index.php?title=Raw_water_pump,_impellers_and_cooling_system
« Last Edit: April 05, 2013, 10:36:40 AM by Stu Jackson »
Logged
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  San Francisco Bay, SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Stu Jackson

  • C34IA - Secretary
  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 59
  • Posts: 6059
    • View Profile
Re: Mysteries of the Oberdorfer - Seal Replacement - REBUILDING A PUMP
« Reply #6 on: March 25, 2012, 09:53:04 PM »

Cleaner - planned to use on engine, but too messy - good to learn on a small piece

This is the impeller on the shaft with the MALE end.  This end fits easily into the engine end, unlike the older female end fitting on the shaft.  The trick is to continue to rotate the new shaft until it sits firmly inside the engine and the impeller blades go all the way into the pump.

The two different sides of the new seals.  Writing faces IN.
« Last Edit: March 26, 2012, 09:25:20 AM by Stu Jackson »
Logged
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  San Francisco Bay, SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Stu Jackson

  • C34IA - Secretary
  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 59
  • Posts: 6059
    • View Profile
Re: Mysteries of the Oberdorfer - Seal Replacement - REBUILDING A PUMP
« Reply #7 on: March 25, 2012, 10:02:23 PM »

The first seal going in, writing facing up, next one writing faces down.

Added to Tech wiki, Engines

There's also a Tech wiki on this, link added there, too

http://www.c34.org/wiki/index.php?title=Raw_water_pump,_impellers_and_cooling_system

« Last Edit: October 19, 2013, 01:45:40 PM by Stu Jackson »
Logged
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  San Francisco Bay, SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

prh77

  • Forum - Petty Officer 2nd Class
  • ****
  • Karma: 0
  • Posts: 155
    • View Profile

Just bought a new Oberdorfer from Depco for $230. Do not know what rebuild parts add up to, but if you have to replace the shaft or cam,$ might be close to new. New style cover plate has an O ring, no more overpriced gaskets. Now I carry the old pump as a spare.
Logged
Peyton Harrison Hull # 597 1988 "Trinity"

Stu Jackson

  • C34IA - Secretary
  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 59
  • Posts: 6059
    • View Profile
Logged
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  San Francisco Bay, SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Ron Hill

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 47
  • Posts: 5732
    • View Profile

Guys : NEVER NEVER buy Oberdorfer parts from any one other than DEPCO (800-445-1656).  

www.depcopump.com

You might as well light your cigars with $20 bills!!

added link to Depco website - Stu
« Last Edit: June 05, 2012, 07:59:24 PM by Stu Jackson »
Logged
Ron, Apache #788

Stu Jackson

  • C34IA - Secretary
  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 59
  • Posts: 6059
    • View Profile

Here's another good link from Maine Sail

http://www.pbase.com/mainecruising/raw_water_pump

Different kinda pump, but the same concepts.  We don't have to bang out our shafts!   :D
« Last Edit: March 28, 2012, 02:53:41 PM by Stu Jackson »
Logged
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  San Francisco Bay, SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."

Stu Jackson

  • C34IA - Secretary
  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 59
  • Posts: 6059
    • View Profile

In some of the OLD literature for M25 engines, there was a discussion that said, essentially, "If you pull out the shaft, you WILL have to remove the pump to reinsert the shaft."

That was because there was a female end on the shaft and a male end on the engine side.

The "newer" (mine's a 1986) Oberdorfer pumps have male end on the shaft and a female end on the engine side.

This makes pulling the shaft and replacing the impeller a SIMPLE job WITHOUT having to take the pump body off the engine.

Here's a picture of the INSIDE of the engine with the female end.  Match that with the picture of the shaft in the earlier posts and you'll see how easy it is.  Make sure the impeller is ALL THE WAY in the pump, or else you won't be able to put the faceplate on.  How do you know if it's in all the way?  Read the last sentence.   :D  In my case, I wondered about it, then just kept turning the shaft until it slid in all the way.

This picture was taken with the pump off to be able to show the inside end of the engine.

OBERDORFER PUMP MODELS

There are two you can choose from: the N 202M-15, which has an O ring on the faceplate and a reversible faceplate, or the standard 202M-15 which uses a paper gasket for the faceplate with only one "inside" face on the faceplate. We have the 202M-15 in this topic.

"Crud" on the Aluminum Timing Belt Cover Above the Pump

Please note the "giveaway" scaling above and around the pump.  While I don't think the seals were the cause of this, because there was no distinct weeping, it appears that the paper gasket between the pump and the engine had deteriorated and the salt water was "creeping" all around the pump.  I'm going to clean that up and repaint.

For repainting engines, see "Engine Paint" here:  http://c34.org/bbs/index.php/topic,4600.0.html
« Last Edit: May 21, 2015, 09:21:50 AM by Stu Jackson »
Logged
Stu Jackson, C34 IA Secretary, #224 1986, "Aquavite"  San Francisco Bay, SR/FK, M25, Rocna 10 (22#) (NZ model)

"There is no problem so great that it can't be solved."
Pages: [1]   Go Up