View Full Version : Can I replace the stock Mayfair 750GPH with a Mayfair 1000GPH?

05-31-2007, 03:43 PM
I have a 2001 205V and I want to replace the 750GPH pump with the 1000GPH pump.

From the few specs I can gather.

-The max current draw on the 750GPH is 2.5A
-The max current draw on the 1000GPH is 3.2A

I don't recall there being any labels on the fuses, but I might be wrong.

I want to make sure I don't have 3A fuse and if I do, is there any problem with switching to a 4A fuse? Is the stock wiring harness capable of handling the increased amperage?

Thoughts? Comments? All are welcome!

05-31-2007, 04:04 PM
I would probably just go ahead and switch it out and see if it works and mess with the fuse & wiring if needed. My guess is you are in the clear, but I'm sure someone will have a opinion with a basis!

06-01-2007, 08:34 AM
Thanks. I just have a feeling it's a 3A fuse and I'm gonna be popping fuses. That's can easily be fixed, but I don't know what gauge wire I will need.

You're probably right, most things are overengineered and I'm probably gonna be alright, but I figured I would ask the "MC Crew" before I acted.

06-01-2007, 10:02 AM
To truely know the required guage of the wire you need to know the current draw and the length of the run. A longer run would need bigger wire. That said, on a boat, I would doubt that the length is significant enough to really be a factor. I would also doubt that they run different size wire for the different circuits since it is easier to use a common size. However, it would be a little more expensive to use larger wire so I could be wrong. In any case, the wire size for 3A or 5A is probably the same. Here is a chart for determining extension cord size:

Conductor size
(wire gage) 10 ft. 25 ft. 50 ft. 100 ft.
18 10 amps 10 amps 10 amps 7 amps
16 13 amps 13 amps 13 amps 10 amps
14 15 amps 15 amps 15 amps 13 amps
12 20 amps 20 amps 20 amps 15 amps
10 30 amps 30 amps 30 amps 15 amps

You can see that 18 gauge wire can handle up to 10A at 50 feet. Chances are, the wiring harness in the boat is either 18 or 16 gauge based on what I have seen when working on mine. I have never actually checked the size, but I would guess it is 16.

I do not think you will have a problem increasing the fuse size. You might also want to inspect the fuse holder to see if it is rated. But again, they may all be the same.


06-01-2007, 12:07 PM
perfect, thanks for the input WTRSK1R!!! That's why I love this forum!!

I'll check tonight!!!