Alternator swap. Help

[Lakerider]

I have a 1997 Larson with a 4.3GL. the factory alternator is only 65amps. It can't keep up with the stereo I have in the boat, when the bass hits the amp gauge almost bottoms out and if I play the stereo turned up high for very long all the lights start to dim with each beat of the bass.
I have a chevy blazer 1995 with a 4.3l engine, I plan to steal the alternator and use it if possible. I have looked and a factory replacement is 105 amps. I know that will or should fix my charging problem since the stereo in my boat was first in this vehicle and I never had the lights dim once and the gauge was rock steady.
Now for the part number of the volvo penta alternator. It has 2 numbers on it
The first is : part no 3856600
The second : no AC165618.

I can try to post a picture of the wiring on the Volvo Penta unit if I need to.
The chevy unit has a large positive wire and a small wire attached close to the positive but on a separate post and
The 2 small wires running into a plug in connector
I have pictures of the back of each alternator if that would help

 

[Lyle29464]

Re: Alternator swap. Help

If you change the unit you will need to buy a marine grade unit. I would look at the wiring first. Duel batteries second

 

[Lakerider]

Re: Alternator swap. Help

I already have dual batteries. The alternator can't stay up What is the difference from an automotive alternator from a marine unit I have tried looking at a Volvo replacement and I can't find anything but 63 or 62 amp units and that's a waste of money

 

[Lakerider]

Re: Alternator swap. Help

Using the parts numbers I supplied in the first post of this thread. Can anyone give a clue where to look for a replacement that is marine grade but with at least a 105 or higher output?
Everywhere I search using my engine model numbers all I get is the weak amped unit I already have. Please someone tell me there is a high output unit that will work.

 

[jerome radtke]

Re: Alternator swap. Help

I have a 1997 Larson with a 4.3GL. the factory alternator is only 65amps. It can't keep up with the stereo I have in the boat, when the bass hits the amp gauge almost bottoms out and if I play the stereo turned up high for very long all the lights start to dim with each beat of the bass.


I could tell you, but, then I, and I am sure many others would not like being anywhere near you on the water. I don't like your car either.

 

[Nickypoo]

Re: Alternator swap. Help

I agree with jerome ^^^ subwoofers are super annoying. I used to be into them back in high school but I hate them now.

Anyway, get a capacitor first and see how that evens things out. If that doesn't work then you will have to go to an aftermarket alternator that isn't official replacement equipment on your boat. You may need to alter the wiring. You could also do a dual alternator setup if you're crafty.

Whatever you do don't use an auto alternator. They can produce sparks that ignite gas fumes and blow up your boat.

 

[Scott Danforth]

Re: Alternator swap. Help

try dbelectrical.com for marine alternators

 

[dypcdiver]

Re: Alternator swap. Help

Buy a hearing aid instead!!!!

 

[Lakerider]

Re: Alternator swap. Help

I have a 1997 Larson with a 4.3GL. the factory alternator is only 65amps. It can't keep up with the stereo I have in the boat, when the bass hits the amp gauge almost bottoms out and if I play the stereo turned up high for very long all the lights start to dim with each beat of the bass.


I could tell you, but, then I, and I am sure many others would not like being anywhere near you on the water. I don't like your car either.

Well jerome radtke that is rude Thanks for the input
You have no idea what my car even is,
the only reason I made reference to the stereo having been in my old car was that the factory alternator worked fine.

My boat doesnt have speakers pointing across the lake like all the wakeboarding boats have, so if you want to be hating turn it towards them.

For your sake, I hope that when and if ever you have a question to post in one of the forums people are more helpful than you.

 

[Lakerider]

Re: Alternator swap. Help

For all the HATERS.
I dont turn my stereo up around other boats
I dont sit at the beach and think everyone wants to hear my music
I only have two 75 watt amps. Just enough power to hear the radio when running across the lake at 30 to 35 mph.

Wind noise is rough to hear over.


Maybe your boats wont go that fast so you dont know what i am talking about. I dont know thats all i can guess.
I am not in the forums to grip or criticise what other people like to do in their boats as long as they aren't being rude to me or my family on the lake.

Here is an idea try to be nice or helpful or just don't comment.
I am sure when it comes time for you to need help you will get better help that way.

And to the people who did offer helpful advice THANK YOU
and I did some research since I asked the difference between automotive and marine and I for sure will only use a marine
i LIKE TO WATCH FIREWORKS OVER THE LAKE
BUT I HAVE NO INTEREST IN BEING THE FIREWORKS

 

[Don S]

Re: Alternator swap. Help

Undersized wiring, poor connections, even a junk battery will cause your problem. Get all of your batteries load tested individually and check all your wiring connections. Checking a battery with a volt meter doesn't tell you anything about the condition of the battery.