MasterCraft Electrics

MrBlean · Posted: Jun 09, 2003 6:24 am Post subject: MasterCraft Electrics

I am seeking to wire a reversible Jabsco ballast pump into the dashboard of my 94 M/C 205 using the reversing switch supplied with the pump. This switch reverses the polarity of the supply to the pump (and hence reverses the pump). There are two spare Accessory switches and like all the switches, appear to be connected via a miniature circuit breaker. Does anyone have any experience of tapping into these? If so, can you advise the correct connections to use? MasterCraft UK have been unable to help and, amazingly, are unable to supply a wiring diagram for ANY of their boats!

Thanks in advance, Jeffrey. Question

jwat142 · Wakeboarder.Commie Joined: 14 Jan 2003 Posts: 1009

I did the same exact thing you are getting ready to do to my '93 MC Prostar 205. It is really hard to explain which wires go where, and honestly, I don't remember. Just remember when you start looking at the wires, is that black is always ground and on mine, the positive wires were orange. One thing you will have to do is buy another fuse. The ones that are in the dash now are too small and will blow after your pump runs for about 10 seconds. I put a 20 amp fuse in mine, I think the stock ones are only 5 amps. I am not familiar with electrical stuff at all. I just took the wires off and pretty much tried to hook them back up the same way except you are going to have to switch the polarity like you said. One other thing, I got mine hooked up the first time and tested it and it worked in my garage. But when I went out to the water, it didn't pump that fast and my bilge pump and blower barely ran at all. All I had to do was switch one of the wires and now everything works great. I'm sorry this description isn't very good, but like I said, I don't have much electrical background at all, so you just have to kind of mess with it. Good luck.

6more · Newbie Joined: 08 May 2003 Posts: 26 City: Upstate, SC

I have a 93 MC and this is how my boat is wired. The switch has a wire that comes off of it that is hot when the switch is on. This wire goes into the harness and comes out somewhere under the dash. You can hook your pump directly into the end of the wiring harness (it is labeled Acc1 or Acc2). The other end of the switch has a pigtail that goes to the fuse which is locate directly below the switch. As the last poster mentioned, you might have to beef up the fuse. If your pump as it's own fuse, you could always disconnect the fuse from the system, but only do that if the pump has a in-line fuse of it's own.

The + and - are supplies to the fuse from the main wiring harness. It is pretty complecated to figure out exactly where it is getting power and ground from, but you don't really need to. Just use the end of the wiring harness located under the dash.

OttoNP · Addict Joined: 13 Jan 2003 Posts: 848 City: MI

You guys should be careful about increasing the size of fuses, expecially if you don't know that much. Forgive me if you already know this stuff, but here's the ideas behind a fuse.

Everything electrical in your boat uses a certain amount of power. Depending on how much power they use they will draw a certain amount of current. A 12 watt accessary will draw 1 amp and a 120 watt accessary will draw 10 amps. An amp is basically how many electrons move through the wire in a certain amoung of time. The more electrons that go through something, the larger wire you need. If the wire isn't large enough, it will get hot and/or melt and possibly cause a fire. To protect against this we have breakers and fuses. Fuses are basically designed to melt at a certain amperage, limiting the current in the wire and protecting it from melting/fire. Every wire guage has an amperage limit and each wire should be fused accordingly. Changing a 5 amp fuse to a 20 amp is a pretty big change, but it should be ok if the wire guages in the circuit are large enough, which you should check.
________
The Cigar Boss

MrBlean · Posted: Jun 11, 2003 1:13 am Post subject:

I'm an engineer and well aware of amp ratings of wire and the role of fuses but it was taking me so long to figure out how the dash was wired I gave up and simply ran a set of 22 amp-capable cables complete with a 20 amp fuse from the battery to the switch and then ran wires to the pump. I've released the Acc 1 switch from the front panel and shoved it to the back of the dash (still connected up) and put the pump switch in its place in the dash. That way I can remove the pump etc and restore the boat to original condition. A quick test indicates all is OK but having installed the pump, I need the boat in the water to ensure it is actually reversing correctly and not just running the same way with the switch in both positions! I'm pretty sure it's OK but because I'm an engineer, I've learned not to make assumptions! It ain't over till the fat lady sings!