Spectra Ventura 150 Clarke Pump Leak Query

[Insight]

Hi Cruisers,

I am trying to commission the Spectra Ventura 150 Watermarker fitted to a yacht I have purchased and have discovered a significant leak between the Clarke Pump centre block and one of the pistons.

The leak is only apparent when running the pump in high pressure mode, it starts as a few drops and periodically turns into a greater trickle of water.

From what I can tell from the MPC5000 the watermaker has 3000 hours on it.

So my questions are:

1. Is this leak repairable and if so which is the seal kit I require? Or is it likely that the block or piston is cracked? What else do i replace at the same time?
2. Is 3000 hours significant and should I have the pump rebuilt? It would seem in Australia this is upwards of $2100!
3. Is there a way to turn the pump into a 200T, it appears the only difference is the clarke pump is 10%?
4. I have no idea of the history of the membrane, should I replace it while I have the whole assembly out of the boat?
5. Should I persist with repairing this Spectra or purchase an alternate watermaker?

Any help or advice would be appreciated.

[Insight]

Photo attached showing the source of the leak.

[belizesailor]

Leaking between the blocks is likely just a seal that needs replacing. It could also be a cracked block, but thats unusual and would likely be visible (pic is fuzzy so cant really tell).

Re membrane. No way to know with out testing. But, the leak will likely cause performance to suffer. So, I would fix the leak then test the membrane. You will need a TDS meter to do this accurately. Test TDS and product water output volume. Testing volume is easy, you just need a graduated cup and a timer.

Replacing seals and membrane is neither expensive nor difficult. Definately whorthwhile to restore the Spectra given the cost of replacing it. And, in the end, you have the most energy efficient 12V water maker on the market.

Im sure Tellie can provide more detailed assistance. Tellie, you out there?

[Insight]

Thanks for the advice, can you provide any guidance on how to dissasemble and replace that seal?

I have been searching for a Spectra manual for dissasembly without luck.

[belizesailor]

Its pretty straight forward, but there are service manuals available. In the past Ive downloaded them from the Spectra site or had them sent to me by Spectra. Check out their site and contact them if you cant find what you need.

Link to my copy of the Clark Pump Repair Manual. Spectra/Tellie can provide more up to date/specific to your model info.

https://www.dropbox.com/s/472q5bfybl...81%29.pdf?dl=0

As with any repair job these days, a digital camera is your friend. Take lots of pics during disassembly in case you need a reminder during re-assembly.

[Insight]

Thank you! I will read the manual and see if i can purchase the correct seals.

[Tellie]

You have a check valve "O-ring" problem. There are two on each cylinder. I would suggest you replace all four. These are a few dollars and a bit of labor on your part. The Clark pump has to be removed from its base to do this job. It is pretty strait forward one the pump is out. Just remove the four Allen bolts that hold the cylinder on and remove the cylinder. You will see three O-rings, the cylinder O-ring and the two check valve O-rings. They cylinder O-ring should be fine. The two check valve O-rings are probably white and are most likely brittle. The replacements are standard black O-rings. Replace these on both cylinders and re-install the pump and you should be fine. If you need further instructions on how to replace theses O-rings give me a call.

Best Regards J.T. Halden
(954) 515-7077
HaldenMarineService@yahoo.com

[S/V Alchemy]

Originally Posted by Tellie

You have a check valve "O-ring" problem. There are two on each cylinder. I would suggest you replace all four. These are a few dollars and a bit of labor on your part. The Clark pump has to be removed from its base to do this job. It is pretty strait forward one the pump is out. Just remove the four Allen bolts that hold the cylinder on and remove the cylinder. You will see three O-rings, the cylinder O-ring and the two check valve O-rings. They cylinder O-ring should be fine. The two check valve O-rings are probably white and are most likely brittle. The replacements are standard black O-rings. Replace these on both cylinders and re-install the pump and you should be fine. If you need further instructions on how to replace theses O-rings give me a call.

Best Regards J.T. Halden
(954) 515-7077
HaldenMarineService@yahoo.com

Now, that's what I call advice!

[NirvanaBob]

You first need to determine which Clark pump you have (-7, -10 or -15). It is stamped into the center block of the pump. Then go to any Spectra reseller and purchase the correct O-ring kit. With the o-rings in hand, go the spectra website and dowload the clark pump disassembly/assembly PDF file and follow the instructions. I had the same leak, which turned out to be that 3 of the four approximately 1/2 inch diamter o-rings that make the seal between the center block and the adjacent side blocks being cracked. Spectra makes the new rings from a different rubber or plastic compound now to eliminate the cracking. This sounds like a daunting task but is much less complex than it is. The o-ring kit contains all o-rings for the entire clark pump and includes an o-ring identification chart. It is very unlikely that a pston is cracked. When you have the side blocks off, run your finger along the interior of the cylinders to check for roughness or scoring from piston travel wear. If REALLY you might consider replacing the cylinders; again I rather doubt you'll find significant wear. Good luck.

[Insight]

Thanks all for the replies, I have a parts list from the Australian importer and will order the recommended parts.