Where are all the Oberdorfers???

[KWKloeber]

Richard

Apologies for not answering sooner.  The notices of new message posts coming thru to me is haphazard at best.

They are M6 double-ended, unequal length thread, stainless-steel studs.
The OEM Kubota studs have an interference fit, but I just use red locktite to hold these.

I use two lengths - 25mm for the Ob flat base pumps and 30mm (a bit long, 27-28mm would be better) to use with the L-clips on the Sw 903/908 pumps or Ob 908 pump.  I buy them wholesale 50 a bag.

PM me if you want a set of studs/nuts (I have no clue how long it takes to get across the border.) 
Or you can get the Kubota steel studs p/n 15221-88210.
McMaster-Carr also has the nuts p/n 94710A103 and 27mm studs p/n 5580N112

-Ken

[Phil Spicer]

Reply 5, Kirk said his Sherwood would not hold a prime. Helped a C30 (1988) friend this weekend and that may be his Sherwood problem. What is the fix to prime the pump short of changing to an Ob pump?
He would like to sail sooner than waiting for a new pump. If the problem is loss of prime, will this continue to happen.
 Checked the impeller and no missing vanes.
 I don't know if the engine is a M25 or M25XP. I expected to see the same engine
as I have since we both have 1988 Catalina's. Mine is the bronze color, his is the silver blue color.
 Time didn't allow for checking for plugged lines or plugged heat exchanger.
I know I'll get some good suggestions, thank you.
   Phil

[scgunner]

Phil,

What is your friend's priming problem, is he losing the prime while the motor is running or is he unable to get a prime when starting? The number one thing that causes priming problems is an air leak, it either won't allow the pump to create a prime when starting or it brake the prime while running.

[Phil Spicer]

Thanks Kevin, I'll check that out when I can get back to the sail club and we have more time. This is a new problem for me. I need some direction. As Ken says, I don't want to go at this as a "wack-a-mole project. As for so many of us, this is a wonderful place to start when you need guidance finding your way through a boat problem.

[KWKloeber]

Phil

Losing prime on the C30 is not the norm, but it is also not unusual to hear that.  I don't know why it occurs but some have reported it.

It possibly seems to occur after the hose drains on a tack — maybe it fills with air and the impeller isn't making a good seal to re-prime - I dunno. I've heard of it on Obs so I doubt the pump brand is necessarily the cause.

Have him check for wear on the pump cover, impeller fit.  If the cover is loosened/removed seawater should flow to it when the seacock is opened. 

Is it a 903 or 908 pump model?
Coat the pump body and cover with SuperLube gel and see if she primes.

The engine (25 or xp) wont make a difference on the pumping.

M-25s and some XPs were copper bronze and later (Westerbeke) ones and XPAs XPACs were Ice Blue.

Ken

[Phil Spicer]

Ken, thanks for the reply so quickly. I'll take this information to the Sail Club in the morning and apply it. So good to have a few ideas for chasing down these problems. I appreciate your wisdom and that of others on our website.
   

[Phil Spicer]

Problem solved ! After checking the impeller on Sunday, we were out of time to do any more investigation as to why we didn't have water flowing out of the exhaust. Got back to the BOAT today armed with some new knowledge thanks to our 34 website. Before pulling the water pump apart, some investigation was done and a fish was found stuck in the intake before the filter.
All is well. Thank you for the help
   Phil

[Noah]

Not the first time I have heard this happening. Not on our website, but my slip neighbor had it happen to him TWICE! How did you find it?

[KWKloeber]

I'm reeling over that fishy line which sounds like a trolling owner casting a wide net, and chumming the forum and angling to lure members into a clickbait!

That's a new data point to add to the "checklist"!

Eons ago I was delivering a C-42 Pullman from Worton Creek to Great Neck LI and stopped in Atlantic City to wait out some heavy weather. We checked the filter every day before firing up and my bro pulled an eel out of it!

[Phil Spicer]

Intake hose before the filter had a fish stuck in it. A blast from a water hose cleared the fish and got things right.