A/C March Pump problems

[rourkeh]

I am having problems with my A/C water pump">raw water pump overheating. I have been using the water cooled, magnetic drive march pumps on my A/C units and I am lucky to get 2 years out of them as they are running 24/7 in warm Caribbean water. I believe the small cooling passages to cool the sealed motor are getting clogged.
My question is does anyone have long term experience with the March AC-5C-MD air cooled pump? I am thinking about replacing my clapped out pump with one of these. Want to know if air cooling lasts long term.

[DotDun]

I use the Cal pump (S580). It's cooled via big piece of bronze as a heat sink between the motor and water. I find them quieter than the March and they usually last 5 years or more. And they are cheaper.

[jstevens]

No experience with the air cooled March pumps, but I've had similar problems with the water cooled pumps. Here in JAX we have a lot silt and small debris that will clog those small water tubes. They can be cleaned using monofilament line pushed through the tubes. Access to the tubes requires removing the face plate. The pumps have an overtemp shut off, so the blockage does not normally damage the pump, but it will shut it down. If the blockage is not removed the pump can be restarted after it cools down, but it will only run for a short time.

John

[svHyLyte]

We are in southwest Florida and have been using air cooled March MDX Pumps on our 16K BTU air conditioning system since it was first installed in 1996. The original pump came as original equipment with the air conditioning system when it was first purchased. That pump lasted 12 years and only failed due to an unrelated water leak that damaged the motor. I installed the replacement pump, a March MDXT, in 2008 and it is still going strong. Key to longevity is regular lubrication of the motor drive bearings. That takes a few squirts of 3-1 oil in the lubrication galleries every few months and you're good to go.

FWIW...

[captain mitch]

Yup, We agree, the air cooled March pump will outlast the water cooled 10 to 1.
I have converted out air con. to those and have not had a problem in 10 years (not with the pump anyway)
Put one on our freezer and it out lasted our freezer.
Now have one as a feeder to the watermaker with great results.
We like them better than the Cal pumps by far.

[spottsvillle]

We use a March Pump and it has worked with no problem for 10+ years. We do carry a spare one just in case. Easily accessed in engine room to R&R.

Norm