Watermaker Failure Due to Absent Weep Hole

[VeinDocFL]

We purchased a two year old cruising cat with a Spectra
400 MKII watermaker mounted under a bed. It had always seemed unusually loud but maintained its water making until this summer when it gradually failed.
Only 650hrs on the unit. Through troubleshooting over the phone with the Spectra rep who installed it we determined that it was the death of the high pressure motor which he says is very rare, and cost $2000 to replace. Upon doing the installation of the new motor I noticed there was some weeping of water from where the magnetic pump attaches to the motor. He had me stop immediately and we determined the pump's seals had failed, cost additional $650. Ok, so what happened? It never had a leak that I noticed. While replacing the magnetic pump I noticed that the new one has a 1/4" hole drilled into the housing but the old one did not. Without the weep hole, the pressure from the pump forced the water past the failing seals, up the shaft of the motor and into the coils eventually shorting the motor and killing it. This would have been prevented had a weep hole been present by relieving the water pressure and providing an indication of pump seal failure through the drip. Anyone else kill their motor this way? Please PM me if so and maybe we can have a chat with the manufacturer.
So check your magnetic pump for the hole, (it may be around back) and if you don't have one I suggest contacting the installer and ask if you should have one. Might save you a few boat bucks down the line.

[Tellie]

I have seen this before. It is a seal failure on the pump head itself. Usually it takes a while for the seal to fail so catastrophically that the salt water backs up into the feed pump motor. There should have been a water trail emanating from the bottom of you feed pump module for some time. As you suggested you should inspect for a weep hole. Also, I would make the weep hole much lower and a bit larger than shown. Use three holes to be extra sure. The holes will not effect performance at all.

[tkeithlu]

Thank you for posting this, Vein Doc. My Spectra will be inspected.

[Boat Guy]

Interesting info... I wonder how much water is expected to weep out.

[Mbenjamin]

I had the same thing happen to me at just about the same number of hours about a year and a half ago in a very remote location. Fortunately I was cruising with a buddy boat who could supply water until the next port. In my case water was actually pouring out the motor vent slots. Had to replace the motor and pump. Very expensive design flaw. I was told that the seal failed due to motor vibration. Technician added extra support to reduce movement. I’ll have to check if the new pump has a weep hole. Definitely don’t want to relive that experience.

[VeinDocFL]

Originally Posted by Mbenjamin

I had the same thing happen to me at just about the same number of hours about a year and a half ago in a very remote location. Fortunately I was cruising with a buddy boat who could supply water until the next port. In my case water was actually pouring out the motor vent slots. Had to replace the motor and pump. Very expensive design flaw. I was told that the seal failed due to motor vibration. Technician added extra support to reduce movement. I’ll have to check if the new pump has a weep hole. Definitely don’t want to relive that experience.

When I removed my pump motor I saw rust streaks down the sides as well. Never really enough water to notice a leak though but enough to ruin the motor. Was yours the Procon magnetic pump as well? Spectra water maker? Shoot me a PM if so.

[VeinDocFL]

Originally Posted by Boat Guy

Interesting info... I wonder how much water is expected to weep out.

None. It’s supposed to be a sealed dry magnetic pump. If any weeping occurs the seals are failing and the motor and your wallet are in imminent danger of damage. It’s supposed to be an early warning mechanism.

[Boat Guy]

rgr...thanks

[Tellie]

Originally Posted by VeinDocFL

None. It’s supposed to be a sealed dry magnetic pump. If any weeping occurs the seals are failing and the motor and your wallet are in imminent danger of damage. It’s supposed to be an early warning mechanism.

Exactly.

[Tellie]

Originally Posted by Mbenjamin

I had the same thing happen to me at just about the same number of hours about a year and a half ago in a very remote location. Fortunately I was cruising with a buddy boat who could supply water until the next port. In my case water was actually pouring out the motor vent slots. Had to replace the motor and pump. Very expensive design flaw. I was told that the seal failed due to motor vibration. Technician added extra support to reduce movement. I’ll have to check if the new pump has a weep hole. Definitely don’t want to relive that experience.

"I was told that the seal failed due to motor vibration. Technician added extra support to reduce movement."


Interesting guess on his part but no.