Oberdorfer N202M-837 will pump cooling water but not A/F

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belladonna
Posts: 105
Joined: Fri Mar 22, 2013 12:20 pm
Location: White Stone,VA - lower Ches Bay

Oberdorfer N202M-837 will pump cooling water but not A/F

Post by belladonna »

Weird subject I know but after changing the impeller, the pump will pump the cooling water but NOT the a/f which I am supplying through a Sea Flush kit into the Groco water strainer with all components tight. I hold the a/f container above the level of the strainer and even move the hose around some but no luck. Any suggestions will be greatly appreciated as I right in the middle of winterizing.
Thanx, Jim
Jim Lassiter
2005 Catalina 350 "BELLA DONNA" # 368
White Stone, VA (lower Chesapeake Bay)
KenKrawford
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Joined: Wed Nov 02, 2005 8:54 pm
Location: Atlanta, GA

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by KenKrawford »

Jim, are you closing the raw water thru hull when using the Sea Flush kit?
Ken Krawford
Message Board Moderator
C350 # 351
Lake Lanier, GA
belladonna
Posts: 105
Joined: Fri Mar 22, 2013 12:20 pm
Location: White Stone,VA - lower Ches Bay

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by belladonna »

Ken, yes I am but remarkably when I tried it yesterday the pump pulled the a/f from the Sea Flush system as it's supposed to do. Go figure!!
Thanx, Jim
Jim Lassiter
2005 Catalina 350 "BELLA DONNA" # 368
White Stone, VA (lower Chesapeake Bay)
Interlude35
Posts: 44
Joined: Wed Mar 18, 2015 7:44 pm

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by Interlude35 »

Jim - It may not be applicable as I have a Perko filter with a flush kit - it requires the handle on the filter top to be moved to be parallel to the inlet/outlet axis to allow flow in the flush mode.
nybor
Posts: 249
Joined: Sun Jan 06, 2013 7:55 am

Re: Oberdorfer N202M-837 cooling issue?

Post by nybor »

I have had it with Sherwood (in fact even Robin Hood says he is leaving the forest). Question looking at the one above, CatalinaDirect says it might cause the engine to run hot at hull speed temps. Has anyone seen this? Does the 350 gang agree on this make and model as a replacement.

thanks

dave
ElizabethG
Posts: 108
Joined: Wed Nov 02, 2016 5:43 pm

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by ElizabethG »

Dave,

I replaced my Sherwood with the p/n Z3936 from CatalinaDirect.

It's the 1/2" Oberdorfer water pump replacement for the 1/2" Sherwood.

I have had no issues with cooling.

(BTW, I don't know what "A/F" stands for in the title)

Bill
C350, #193
Atlanta (Home) / Charleston, SC (Boat)
KenKrawford
Posts: 614
Joined: Wed Nov 02, 2005 8:54 pm
Location: Atlanta, GA

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by KenKrawford »

Antifreeze ??
ElizabethG wrote: Thu Mar 14, 2024 7:29 pm (BTW, I don't know what "A/F" stands for in the title)

Bill
C350, #193
Atlanta (Home) / Charleston, SC (Boat)
Ken Krawford
Message Board Moderator
C350 # 351
Lake Lanier, GA
nybor
Posts: 249
Joined: Sun Jan 06, 2013 7:55 am

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by nybor »

Thanks. I didn't notice the A/F in the subject line. Have no idea what it stands for, maybe at full throttle? That is what CatalinaDirect said might happen. I saw another response that mentioned something about a Flush kit. Maybe that is the "F"?

dave
Flagmanmike
Posts: 25
Joined: Fri Mar 27, 2015 10:42 am

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by Flagmanmike »

I replaced my Sherwood with the Oberdorfer N202M-908 in 2017. It has been super reliable since then. Recommend it highly. I Bought it from Sales@pumpsandpartsonline.com and the packing slip said Cardinal Pump, St. Louis, MO 314-628-0100 . In 2017 the price was $312 and bought a spare impeller $29.Good Luck and Fair Winds

Mike Cronin
FlagShip Hull No 314.
nybor
Posts: 249
Joined: Sun Jan 06, 2013 7:55 am

Re: Oberdorfer N202M-837 will pump cooling water but not A/F

Post by nybor »

Fantastic. So the impellers from the Sherwood won't work?

dave
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