European boat owners: Tell me about your holding tank fitting

[Tedd]

I'm the proud owner of a TES 246 Versus, a boat made in Poland. I'm trying to get a pumpout adapter for it but I'm having trouble identifying the thread size of the pumpout deck fitting. Hoping someone here with a European boat can set me straight.

The closest metric size I can find is M42 fine pitch, but it doesn't actually measure very close to that. The closest plausible non-metric thread I can find is NPT straight 1-1/4, but that's even further from what I measure on the actual fitting.

Bonus question: Is the standard pumpout adapter fitting a Camlock 1-1/4? It looks like that, but I can't find any reference confirming it.

 

[Ralph Johnstone]

Do you have a thread gauge ?

 

[sail sfbay]

Congrats on your new sailboat!!

Please post a photo of what you are trying to find. Is it a pumpout fitting? Pumpout stations I am familiar with use an open nozzle with rubber collar to insert into a deck's female fitting like the one below.

Photo?

 

[Peggie Hall HeadMistress]

This one should work in any deck pumpout fitting, metric or otherwise and will mate up with any dockside pumpout that uses a cam connection:

Pumpout Nozzle X 1.5" Male Quick Clamp Adapter (272QC-150)

The standard universal Pumpout Nozzle is attached to a male 1.5" Quick Clamp (camlock) Adapter so it can be interchanged with other deck adapters.

www.edsonpumps.com

There is a downside to it: you have to jam it into the deck pumpout fitting and then stand there and manually keep it jammed in till pumpout is complete. Otherwise it won't keep the necessary vacuum seal.



--Peggie

 

[Tedd]

Thanks, @Peggie Hall HeadMistress . I'd like to avoid the push-and-hold kind, but it's a good option to have.

 

[Tedd]

I eventually figured out what the threads are. They are 1-1/4 NPS.

I was worried that they might be something metric because the boat is from Poland. Weirdly, almost everything I've found on the boat so far has been U.S. units.

 

[jssailem]

almost everything I've found on the boat so far has been U.S. units.

Clever Poles...

 

[Tedd]

Clever Poles...

It's actually a bit annoying because I have to carry two sets of tools on board. I would have preferred if they'd just left it metric. I have to carry metric tools for the engine, anyway, and it would be easier just to have one set.

 

[jssailem]

SAE. METRIC.
With a little care the can be close enough, mostly.
You just need to be specific about the selection.
I am particularly fond of my metric adjustable spanner, loaned to me by my friend @LeslieTroyer the engineer.

It is a British design.



He said it will work on my Perkins British engine.

 

[Tedd]

I am particularly fond of my metric adjustable spanner, loaned to me by my friend @LeslieTroyer the engineer.

That's amazing, I have an Imperial spanner that's nearly identical!

 

[Peggie Hall HeadMistress]

If the builders used US fittings, the deck fittings (water, pumpout, fuel) will be 16 TPI (threads per inch) if the boat was built before the mid-'80s. That was when they all changed to 11 TPI...not sure of the exact year.

--Peggie

 

[Parsons]

1.25 inches seems like a really small pumpout deck fitting.
What Defender sells is either 1 5/8 or 1 7/8:
Dometic Deck Fitting Pump Out Adapter is available in (3) Size:

• Model 310343502:
  • Deck Fitting Cap OD: 1-7/8"
  • Thread Diameter/Type: 1-1/2" MPT (Note: Product packaging shows this specification only)
  • Threads per Inch: 11.5
  • Threads per Quarter Inch: 2-3/4
• Model 310343503:
  • Deck Fitting OD 1-5/8"
  • Thread Diameter/Type: 1-1/4" MPT (Note: Product packaging shows this specification only)
  • Threads per Inch: 11.5
  • Threads per Quarter Inch: 2-3/4
• Model 310343504:
  • Deck Fitting OD 1-5/8"
  • Thread Diameter/Type: 1-1/4" MPT (Note: Product packaging shows this specification only)
  • Threads per Inch: 16
  • Threads per Quarter Inch: 4 (fine thread)

*How to determine which NozAll adapter will fit a deck pump-out fitting requires two simple measurements from the cap of the deck fitting.

1. Measure the outside diameter (O.D.) of the cap threads (A)
2. Count the number of threads per 1/4-in. of thread length (B)
   • Multiply that number by 4 to determine threads per inch (TPI)
3. Use Information below to determine which NozAll item number your measurements apply

 

[Tedd]

Thanks, @Peggie Hall HeadMistress . My holding tank pumpout deck fitting appears to be 1-1/4 NPS which, according to Machinery's Handbook, is 11-1/2 TPI. That also matches my measurements, to the accuracy that I was able to measure using calipers (my thread pitch gauge doesn't have 11-1/2 TPI).

Thanks for the NozAll information, @Parsons . One of the reasons I was interested in determining the thread size in the first place was to avoid the exorbitant prices that marine suppliers are charging for these fittings. For example, the Model 310343504 fitting you listed is $37.95 at Environmental Marine but, if I'm correct that it's 1-1/4 NPS, the exact same fitting is available from McMaster-Carr for $4.11. I have already screwed a 1-1/4 NPS fitting into the hole and it appears to match perfectly.