Voltage Drops While Advancing Throttle To Max Power Help.....

[BornBlue82]

I just recently purchased a 01 bayliner capri sport with the 4.3L engine. I replaced the battery and serviced everything before taking it out for my first time. The guy I bought it from is a friend of mine, who told me that he notice the voltage problem. So that was a known problem to me. Which is also the reason that I replaced the battery. So when I took it out, everything worked great. However, when I advanced the throttle wide open I noticed the voltage dropping. It took about a little bit (don't know the exact time) to get down to low voltage range, then the battery light came on and the alarm sounded. I then cut the throttle back down the idle and the voltage rose back to btw 12 and 13. I removed the alternator to take it to advance but they said they didnt have the code to test it. Has anyone else experienced this problem? Could it be anything other than the alternator?

 

[Don S]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

I removed the alternator to take it to advance but they said they didnt have the code to test it.

You don't need a code to test an alternator. You need someone that knows what they are doing. You probably have a shop in your area that specializes in starters, alternators, and electric motors. They would be the ones to take it to.

Do you have a Merc serial number for your engines, to many different combinations for just saying it an 01 4.3

 

[Don S]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

I removed the alternator to take it to advance but they said they didnt have the code to test it.

You don't need a code to test an alternator. You need someone that knows what they are doing. You probably have a shop in your area that specializes in starters, alternators, and electric motors. They would be the ones to take it to.

Do you have a Merc serial number for your engines, to many different combinations for just saying it an 01 4.3

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

You don't need a code to test an alternator. You need someone that knows what they are doing. You probably have a shop in your area that specializes in starters, alternators, and electric motors. They would be the ones to take it to.

Do you have a Merc serial number for your engines, to many different combinations for just saying it an 01 4.3

Ok I took the alternator to a specialist and he hooked it up. It ran good until he put a load on it, then it decreased. It was making a loud noise. He said that the bearins were going and it was slipping. So I guess that is the problem. But my engine is a 2000 mercury mercruiser Alpha 1 4-211015n1. Thanks for the reply.

 

[Don S]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Year is meaningless and that is not a Merc serial number. Serial number is something like this example 0M123456..

 

[Eric 3.7LX Alpha 1]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

See if there are any alternator/starter rebuild shops in your area. If you are handy there are rebuild kits out there you can do it yourself.

If you buy new make sure to get one rated for Marine.

 

[Ike-110722]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

I would recommend buying new. I have the same 4.3L engine in my Sea Ray. Last year I replaced the alternator. A brand new Mallory alternator bought through iboats was $209.60 including shipping and handling. The peace of mind was worth it. (No I do not work for, and other than the forum, I am not affiliated with iboats. I just got a good deal.) No rebuild necessary, just bolt it on and hook it up. No worries about how long will it last, and so on.

 

[figaro]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

I just recently purchased a 01 bayliner capri sport with the 4.3L engine. I replaced the battery and serviced everything before taking it out for my first time. The guy I bought it from is a friend of mine, who told me that he notice the voltage problem. So that was a known problem to me. Which is also the reason that I replaced the battery. So when I took it out, everything worked great. However, when I advanced the throttle wide open I noticed the voltage dropping. It took about a little bit (don't know the exact time) to get down to low voltage range, then the battery light came on and the alarm sounded. I then cut the throttle back down the idle and the voltage rose back to btw 12 and 13. I removed the alternator to take it to advance but they said they didnt have the code to test it. Has anyone else experienced this problem? Could it be anything other than the alternator?

are u sure the belt was tight ?

 

[generator12]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

I'm with Figaro. It's been known to happen that a loose belt will show itself under high rpm push and not do so at lower rpm. Not common but it does happen.

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Year is meaningless and that is not a Merc serial number. Serial number is something like this example 0M123456..

View attachment 194889

Sorry, S/N OL925719

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

are u sure the belt was tight ?

Yeah I checked the belt, it was on pretty snug.

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

See if there are any alternator/starter rebuild shops in your area. If you are handy there are rebuild kits out there you can do it yourself.

If you buy new make sure to get one rated for Marine.

I would recommend buying new. I have the same 4.3L engine in my Sea Ray. Last year I replaced the alternator. A brand new Mallory alternator bought through iboats was $209.60 including shipping and handling. The peace of mind was worth it. (No I do not work for, and other than the forum, I am not affiliated with iboats. I just got a good deal.) No rebuild necessary, just bolt it on and hook it up. No worries about how long will it last, and so on.

I cross referenced the number of the alternator which is Mercruiser 862031 and I found an alternator on Amazon for $93 marine rated alternator. We'll see how well it works.

 

[achris]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Sorry, S/N OL925719

That's the transom serial number, not the engine....

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

That's the transom serial number, not the engine....

Sorry I'm new to this. I got the number off of the manual. I will get it off of the engine when I get home this evening.

 

[Don S]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Ok I took the alternator to a specialist and he hooked it up. It ran good until he put a load on it, then it decreased. It was making a loud noise. He said that the bearins were going and it was slipping.

Did you ask your specialist how much to rebuild it? It's usually much less than a new one, even a cheap offshore aftmarket alternator.
They also look brand new if it's any kind of alternator shop.

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Did you ask your specialist how much to rebuild it? It's usually much less than a new one, even a cheap offshore aftmarket alternator.
They also look brand new if it's any kind of alternator shop.

I asked him, but he said he didn't have the parts to do a marine battery. He's been in business for 30+ year. He had an alternator that cross referenced with the part number. He said that the new alternator was ordered as a forklift alternator, that they use the same type. So I left and decided to do my own research.

 

[Don S]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Marine alternators are shielded to prevent sparks from igniting any stray gas fumes that could be present in the bilge. Not sure a fork lift would need that.

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Marine alternators are shielded to prevent sparks from igniting any stray gas fumes that could be present in the bilge. Not sure a fork lift would need that.

That's what I was thinking

 

[achris]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

I asked him, but he said he didn't have the parts to do a marine battery.

Testing an alternator (marine or otherwise) does not require a 'marine' battery, any battery will do for testing.

He's been in business for 30+ year.

Sounds like he's either, total incompetent, or he doesn't want your business. (This is the same guy who told you he needed codes to check the alternator. :facepalm

He had an alternator that cross referenced with the part number. He said that the new alternator was ordered as a forklift alternator, that they use the same type. So I left and decided to do my own research.

I'd also be researching a new auto-electrician.... A marine alternator and a forklift alternator are quite different... A forklift alternator is NOT marine rated....

 

[BornBlue82]

Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Testing an alternator (marine or otherwise) does not require a 'marine' battery, any battery will do for testing.



Sounds like he's either, total incompetent, or he doesn't want your business. (This is the same guy who told you he needed codes to check the alternator. :facepalm



I'd also be researching a new auto-electrician.... A marine alternator and a forklift alternator are quite different... A forklift alternator is NOT marine rated....

I meant to say that he doesn't have the parts for a marine alternator. The guy from advance auto parts said that he didn't have the code, which is why I went to this guy. He had the equipment to test any alternator or starter. As for the alternator that he had, the part number is the exact same as the part number for the marine alternator. However, I agree with you, I feel like he didn't want my business. He was too quick to try to sell me an alternator. Thanks for the reply.