March AC pump motor freezing up

[67hat34c]

Cal-Pumps are complete Junk, no not use these pumps. March is about the best out there, Stick with it. March pump in our boat was 3 yrs old when we sold the boat and still running as far as I know. It ran 365days a year and many many hours each day in FL.

I went throug a cal pump every 8 to 12m for a while. They are not a mag drive. The shaft has a crappy little rubber seal with a small band around it to keep sea water out of the electric motor. This is an awful system. Pump is pretty though, shiney stainless and brass. Funny thing is that the pond pump and marine pump are identical but marine has shorter warranty and costs more money.

Regarding pump location: you may consider re location. Remember the pump must be higher than the sea strainer and discharge from pump must be condinuous up slope to the unit, no dips in the line. Pump cant push an airpocket.

[spcoolin]

I got 8 years out of the original so I replaced it with the same pump. That said, the replacement has more noise than the original, sounds grumbly. Also, it seems to run pretty hot - an IR temp gun says 115 F. I never measured the original so I have no reference. Looks like good water flow and the AC unit likes the cooling. I was pretty careful to have good sealing at the threaded fittings and hose clamps - double clamps and tape/leak lock sealant on the threads so I should not have any air/cavitation but there are no clear hoses to verify 100%. Also I had to dissassemble the wet end to rotate the output and I verified all the parts and sequence.

Any thoughts on the noise or heat?

Thanks,

George

George...You aren't using that AC 2C March for your 16K system are you ?

If so...It won't pump enough water & your head pressure should run higher than we discussed in your other thread...even with a squeaky clean condenser it is not enough unless your seawater is very cold.

That pump is only rated for about 250 GPH which is only good for 12K or one ton...
You need the next size up AC 3C MD March which is rated for 500 GPH & up to 24K (two tons)

Is it too late to take this one back because of the noise ?

Steve~

[67hat34c]

Agree on pump size. Get the biggest one you can. Also need to make sure hose size is also proper.

[spartonboat1]

Allow me to re-visit my Cal-Marine recommendation, after reading all the issues others have had. I may well be incorrect to recommend the CM unit, although it has given good service, up until the mounting let loose (not CM's fault, but I notice that they have upgraded the mounting to be two large SS hose type clamps.

My Cal-Marine flew into two pieces, after its mounting bracket became loose due to the rubber mounting devised by my prior tech slipping out of place. Yes, the CM pumps are two stainless shells- one end is an empty shell, while the other has the pump mounted in it. The two shells are press fitted and the shells are sealed with some type of RV sealant or other blue sealant at the press fit. Obviously the blue sealant was not enough to hold the two shells together, if the mounting bracket was not tight to the shells. Personally, I would prefer to see the two shells held together by threaded fasteners (nuts and bolts).

1) When the two SS shell pieces came apart, the fill of dielectric grease/oil went all over and was quite a mess. It is about the consistency of pea soup and a greasy mess.
2) CM was totally unhelpful (!) on any of my issues, when I called them. They were polite but, sorry, you're on your own. I.e. would not provide the name of the vendor or part number of the dielectric fluid, or the volume recommended and would not send me any and was not willing to factory re-assemble the unit.

I did not expect warranty support, as this unit is several years old and had been running for probably 100-200 hundred hours. But did not enjoy getting blown off!

Have said all that, I am going to take a closer look at the Dayton unit carried by Grainger. Still a little leary of March...not crazy when a unit is Epoxy enclosed (if it still it).

[GJH]

Try calling our old friend Depco 800.446.1656; they will recommend a proper replacement. My Oberdforfer 104M sure is dependable and relatively quiet ,but may be overkill for the OP's use: it feeds five units on my boat. You can get a rebuild kit from Depco (80 bucks as i recall); which I put in this winter after at least 4 years of hard use. Anyway pretty hard to beat the Oberdorfers and Marches designed for this purpose.

[Reefgeorge]

Sorry, I had a typo induced by the right pump being shipped in the wrong box/label. This system is two 16k btu units being fed by a new and still noisy AC5CMD230/PM1000. March confirmed that a 115F case temperature is normal but the noise is not typical. They said that if I wait a few days, the noise may subside.

The set up has 1" intake plumbing and 1/2" output plumbing split to the two condensors. Water flow is as good or better than new.

[Boatsb]

That's not the sealed pump others referred to. It will handle 3 tons in warm climates and 4 in the north.

I think they are about 1K gal/hour and I have had one a few years running on my boat with no issues.

Its a great pump for most applications. I see you have the 230 V one. Are your AC system 230? I have all 115 and wish they were 230.

[Reefgeorge]

Yes my water pump and both of my AC units are 230V.

[Boatsb]

Lucky you. I am thinking of rewiring the main in my boat to a 50 A 125/250. This way I can pull 230 of a panel and still run all my 115 stuff. I have to double check but I believe if there is truly 50A at the power pole I can pull about 20A on the 220 and still have 30A for the 2 115V panels

Then I can slowly convert things over.

[spcoolin]

Ok George...That is the correct pump...and a good one at that....

I noticed you said you had to remove the head to relocate the output...

Usually the source of noise is in the head of those pumps and two things you need to be sure of since you had it apart...

The ceramic spindle that the impeller rides on...cracks very easily if you were re-assembling the head to the motor under a bind...My helper broke one the other day before I could say STOP !...I heard the small click sound & it was too late...
Also be sure that the ceramic washer is in place on the spindle between the inlet cover & the impeller...

Most times the pump will run with either of these things not right...But it will be noisy, and will wear itself out in short order...

Steve~