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Recommendations for pex in Marine use.

Discussion in 'Technical Discussion' started by Eddieclemons, Apr 18, 2021.

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  1. Eddieclemons

    Eddieclemons Member

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    I have some places in my fresh water system that drip/leak and are nest of connections. I plan to replace them with pex. There are a few questions I am researching.

    1. I was told that stainless crimp clamps are considered to have more corrosion resistance than the brass compression rings?

    2. Brass vs plastic fittings? Not all fittings are even found in plastic.

    3. If the brass fitting barb allows room for a double crimp clamp, shall I double up? There is a minimum clearance for the clamp to fitting down the pex
  2. Capt J

    Capt J Senior Member

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    Nobody really crimps them on yachts, the vibration and expansion causes them to pop the crimps or for it to cut into the hose. Generally they use push lock connectors......stick to one system and order extra fittings........seatech (now Aqualock) is popular, whale is popular. The Home Depot stuff isn't exactly the same size and doesn't always work in place of marine brands.

    SeaTech Is Now AquaLock™ (watts.com)

    Pipework (whalepumps.com)
    Eddieclemons likes this.
  3. Eddieclemons

    Eddieclemons Member

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    Thanks, I would have thought the crimped stainless on pex with brass fittings would have been a pretty solid system, I guess not. The aqua lock looks good, but that's alot of rings to fail, but it would be easily replaced.
  4. Capt Ralph

    Capt Ralph Senior Member

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    I think your talking about Polybutylene and clamps.
    Now outlawed in most codes and in your home, may not be insurable.
    Pex and it's slip in fittings (Polybuty replacement) are another evolution in plumbing head aches.

    https://www.polybutylene.com/poly.html
  5. Capt J

    Capt J Senior Member

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    No, they've been crimping PEX in houses these days.
  6. Norseman

    Norseman Senior Member

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    Have PEX in my boat, 20 year old system: Seems to work good,
  7. Eddieclemons

    Eddieclemons Member

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    I meant O rings to fail with the Aqua lock, sorry for the typo.
  8. Eddieclemons

    Eddieclemons Member

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    Connections are ???
  9. Eddieclemons

    Eddieclemons Member

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    I was looking at these crimped on brass vs Aqua lock. Plenty of room to double clamp. Screenshot_20210418-140436.png Screenshot_20210418-140436.png
  10. rtrafford

    rtrafford Senior Member

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    Perhaps not mentioned here, try to avoid using brass on a boat. If you use stainless clamps, use the quality ones usually not found at Home Depot or Lowes.
  11. Capt Ralph

    Capt Ralph Senior Member

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    I hope not, When using Polybutylene and clamp, the clamps, eithey alloy or monel were a failure topis.
  12. Capt Ralph

    Capt Ralph Senior Member

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    Once O rings set, they are pretty much a lost thought. No worries here.
  13. Capt Ralph

    Capt Ralph Senior Member

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    Only returned to a real (not hospital) land bed in a real house (not hotel) this last week.
    Now modern plumbing with mixed metal fitting examples??
    I'm going back to my 43 year old boat where it's safe, All copper.
  14. Eddieclemons

    Eddieclemons Member

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    I am going to clean a few areas with Aqua Lock and Pex. Thanks for all the comments. Now to see who has an good selection and price.
  15. Norseman

    Norseman Senior Member

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    Looks like push-in plastic connectors.
    Have not really paid attention as there has been no leaks and no need for maintenance.
    The water system holds pressure for looong time after I turn the breaker off, probably overnight, I am impressed.
  16. Eddieclemons

    Eddieclemons Member

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    I placed a order for Watts Aqualock from Freshwatersystems. I will let y'all know how it goes.
  17. Capt J

    Capt J Senior Member

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    You DO NOT want to crimp the connections. They pex expands and contracts with temperature changes and with vibration from running the boat. It is a major failure point. Either the crimps cut through the hose, rot and fall off, or expand. Use the plastic push lock connectors like every yacht builder under 100' and be done with it. The o-rings don't fail and the connectors generally last 20 years.