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

B

BornBlue82

Seaman
Joined
Feb 11, 2013
Messages
59
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

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
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.
Click to expand...

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

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
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.
Click to expand...

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
 
B

BornBlue82

Seaman
Joined
Feb 11, 2013
Messages
59
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Don S said:
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
Click to expand...

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

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
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..

Merc V8 SN Location.jpg
 
Eric 3.7LX Alpha 1

Eric 3.7LX Alpha 1

Captain
Joined
Mar 27, 2010
Messages
3,008
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.
 
Peter Eikenberry

Peter Eikenberry

Chief Petty Officer
Joined
Sep 3, 2007
Messages
408
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.
 
F

figaro

Cadet
Joined
Nov 3, 2010
Messages
23
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

BornBlue82 said:
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?
Click to expand...

are u sure the belt was tight ?
 
G

generator12

Senior Chief Petty Officer
Joined
Jul 9, 2010
Messages
666
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.
 
B

BornBlue82

Seaman
Joined
Feb 11, 2013
Messages
59
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Eric 3.7LX Alpha 1 said:
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.
Click to expand...

Peter Eikenberry said:
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.
Click to expand...

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.
 
B

BornBlue82

Seaman
Joined
Feb 11, 2013
Messages
59
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

achris said:
That's the transom serial number, not the engine....
Click to expand...

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

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

BornBlue82 said:
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.
Click to expand...

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.
 
B

BornBlue82

Seaman
Joined
Feb 11, 2013
Messages
59
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Don S said:
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.
Click to expand...

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

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
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.
 
B

BornBlue82

Seaman
Joined
Feb 11, 2013
Messages
59
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

Don S said:
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.
Click to expand...

That's what I was thinking
 
achris

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

BornBlue82 said:
I asked him, but he said he didn't have the parts to do a marine battery.
Click to expand...

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

BornBlue82 said:
He's been in business for 30+ year.
Click to expand...

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:)

BornBlue82 said:
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.
Click to expand...

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....
 
B

BornBlue82

Seaman
Joined
Feb 11, 2013
Messages
59
Re: Voltage Drops While Advancing Throttle To Max Power Help.....

achris said:
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....
Click to expand...

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.
 
You must log in or register to reply here.
Top