help with boat install

[boatben]

Hi guys, bare with me, this may be long. I'm installing a stereo for the first time and it's in my boat. I have 1 alpine MRP 600x1 and 1 RF P400.4 amp. I paid a guy to come out and install it (rip me off). He ran both amps off 1 8 gauge cable. The amps were cutting out so I checked it out and did a little research to find out that the power cable was way too small. So I went to the audio store and bought a 0 guage amp kit. I installed everything and it worked perfectly for awhile and then my 4 channel amp started cutting out. Since it's a boat I have to ground back to the negative terminal on the battery. I obviously didn't have enough 0 gauge so I ran 4 gauge ground cable which I assume is too small and I should be using 0 gauge.

I've done some research on the install bay 0 gauge amp kit I bought and found out the 0 gauge is not a true 0 gauge. So here's my question...should I buy 0 gauge cable for the long ground I need to run or should I get 2 gauge? I guess I could replace all the power and ground with true 0 gauge, but I'm trying to keep cost down and not even sure if true 0 gauge would fit the fuse holder and distribution blocks provided in the kit?

Here's the kit I bought. The Install Bay AK01 - 0-2 Gauge Amp Kits - Sonic Electronix

Thanks in advance for any suggestions!

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[hispls 5,000+ posts]

4 guage should have been adequate for those amps. Proveded your connections at the terminals are good, the only thing I could think is that either you got some water in something and damaged it or your battery/generator are inadequate to keep these amps powered.

 

[boatben]

so it's not an issue if I have supposed 0 guage for the power and 4 gauge for the ground.

I guess it's possible I have a lose connection somewhere. I'm fairly certain nothing got wet, and I have 2 deep cycle batteries with a perko switch so I don't think that's the issue.

 

[n2audio 5,000+ posts]

big batts are nice, but a lot of boats don't have much for an alt (50ish amps) so it's not uncommon to see voltage dropping below 12v with high power amps. Some amps are more sensitive to voltage loss than others which could lead to a low voltage shut down.

 

[keep_hope_alive Premium Member]

monitor the system voltage with a volt meter at all times.

you are correct that the amp kit you have is not true 1/0, that is common with cheap amp kits. power and ground should be equal in size, no exceptions. but true 4 awg would be sufficient for your system. any more than 80A of draw and you need a battery bank and shore power to recharge them after each use.

how many batteries do you have and are they new? what size motor? what kind of boat?

i've done several boat installs, they are all a unique challenge, but can provide very good results. i try to install solar panels to keep the batteries fully charged if the boat can sit in the sun. that way the owner can be assured of a full charge when they get on the boat since (as mentioned) boat alts are sometimes very small.

 

[boatben]

monitor the system voltage with a volt meter at all times.
you are correct that the amp kit you have is not true 1/0, that is common with cheap amp kits. power and ground should be equal in size, no exceptions. but true 4 awg would be sufficient for your system. any more than 80A of draw and you need a battery bank and shore power to recharge them after each use.

how many batteries do you have and are they new? what size motor? what kind of boat?

i've done several boat installs, they are all a unique challenge, but can provide very good results. i try to install solar panels to keep the batteries fully charged if the boat can sit in the sun. that way the owner can be assured of a full charge when they get on the boat since (as mentioned) boat alts are sometimes very small.

I have 2 everstart deep cycle batteries. I think they're about 2 years old, but with minimal use. I set the perko switch to the 2 position when the engine is off so the 2 amps are only running off 1 battery. I put the battery charger on it yesterday and the one that runs my amps is at 75%, so I turned on the stereo and turned it up and sure enough both amps were cutting out at high volumes which leads me to believe it may be a grounding issue...hopefully. The boat is an Advantage 21 SR bowrider and it has V8 Mercruiser EFI 5.7L. I THINK it's a 70amp alternator.

Do you think I should replace the "0" gauge wire that came with the kit with true 0 gauge for the power and ground? Keep in mind the power and ground are both long runs, about 18Ft each.

 

[keep_hope_alive Premium Member]

the "0 gauge" you have is closer to 2 gauge, which should still be fine as long as both power and ground are that size. you should have good quality ring terminals on the wire terminations at the battery. i assume you have a distribution block for power and ground at the amps?

you need to monitor the voltage when the amps cut out. if it's below 11.5VDC, then you have identified the issue as low voltage.

You can easily upgrade the alt on that 5.7L which is probably a good idea if you plan on running the stereo often. 160A alt minmum.