PLEASE Help with overcharging issue

[Thoroughbred]

My Merc 150 Offshore is also overcharging. I have dual batteries and one died last year so I replaced the one, the other seems fine. While at idle volt meter is 13-14 but while under way as it goes up over 16 and sometimes pegs. Fish finder goes into protection/shutdown mode because of overcharging etc. Could it be because I only changed one (dual purpose) battery? I did have a trim switch problem last summer and fixed that but didn't think the two were related. Now my bilge pump and bait box pumps don't work and I think they fried due to overcharging.

Any/all ideas? Should I have bought 2 new batteries at that time even though one was fine?

 

[Laddies]

Re: PLEASE Help with overcharging issue

Sounds like the regulator went bad.

 

[PondTunes]

Re: PLEASE Help with overcharging issue

yep, bad voltage regulator!

 

[Thoroughbred]

Re: PLEASE Help with overcharging issue

In a car motor that was my first choice but surprised it is in boat OB but then again I am still a newbie with OB's. Read a few replies where it said their were no voltage regulars in some motors.

Anyway thanks guys I really appreciate it!!!

Now does it really matter if I buy a Mallory, CDI or Sierra?

 

[hkeiner]

Re: PLEASE Help with overcharging issue

Some small motors and some old motors do not have voltage regulators, only rectifiers to convert AC to DC current. You motor has a voltage regulator. CDI is a good choice for a replacement voltage regulator.

 

[Thoroughbred]

Re: PLEASE Help with overcharging issue

Thanks and as most times the best is the most expense I guess you get what you pay for though.

Is there any way to test a voltage regulator? Probably not but would hate to spend the $130 only to find out it isn't the problem.

Thanks again

 

[PondTunes]

Re: PLEASE Help with overcharging issue

While at idle volt meter is 13-14 but while under way as it goes up over 16 and sometimes pegs.

Sounds like you've already tested it! Throw a good multimeter on there and re-check the voltage if you don't trust your dash gauge! A meter should tell you how much it's actually putting out it might be upwards of 18 -20 or more un-regulated...

 

[hkeiner]

Re: PLEASE Help with overcharging issue

If there is no output or constant high output, then there may be other causes other than a faulty voltage regulator. If the output is erratically high (such as yours) it is a faulty regulator. I had the same symptoms on my motor last year and replaced the voltage regulators to solve it.

There are two voltage regulators on your motor and if you do not want to replace both of them, you can use a voltmeter (touching the wires coming directly from each regulator with the motor running) to determine which of the two regulators is causing the erratic high voltage. Doing bench tests (using an ohmmeter with the regulators removed) are generally not too helpful when the regulator is acting erratically only when the motor is running.

Sometimes is it best to just replace both regulators right away.

 

[Thoroughbred]

Re: PLEASE Help with overcharging issue

If there is no output or constant high output, then there may be other causes other than a faulty voltage regulator. If the output is erratically high (such as yours) it is a faulty regulator. I had the same symptoms on my motor last year and replaced the voltage regulators to solve it.

There are two voltage regulators on your motor and if you do not want to replace both of them, you can use a voltmeter (touching the wires coming directly from each regulator with the motor running) to determine which of the two regulators is causing the erratic high voltage. Doing bench tests (using an ohmmeter with the regulators removed) are generally not too helpful when the regulator is acting erratically only when the motor is running.

Sometimes is it best to just replace both regulators right away.

and what brand did you replace yours with?

 

[hkeiner]

Re: PLEASE Help with overcharging issue

I bought the CDI regulators

 

[glhay]

Same overcharging issue Merc 150HP (1996 carbed

Same overcharging issue Merc 150HP (1996 carbed

I also have a 1996 Mercury 150HP V6 carbed outboard motor and Maxum 1900XR bowrider boat and I am having the same overcharging issue. While at idle volt meter is sometimes in the 13-14 range but while under way as it goes up over 17 and it usually will peg at some point. It was more erratic at first as you could some times run for an hour or more at 1/2 throttle and it would not happen. But now it is getting worse and usually pegs at anything but idle.

Thinking it was the regulator as the battery was a new marine cranking battery and the connections are all clean and solid. I choose to purchase one new regulator (mercury replacement part) and try to change out one regulator at time to see if one was bad. This DID NOT solve the problem. Same thing happeds regardless of which regulator is changed out.

Is it likely that both regulators are bad and have to be replaced. Have I done the wrong thing by putting in a new good regulator with perhaps a bad one and now wrecked it as well?

Any advice would be appreciated.

 

[glhay]

Same overcharging issue on a Merc 150HP (1996 carbed)

Same overcharging issue on a Merc 150HP (1996 carbed)

My Merc 150 is also overcharging. While at idle the volt meter is usually 13-14 but while under way as it will eventually go up over 16 and will usually peg at some point. If running for some time the battery will leak acid into the battery box due to overcharging.

In an attempt to fix, I purchased one new regulator from local Merc dealer and replaced first one then the other regulator. No matter which was changed out the same overcharging condition would occur. Is it likely that both of the regulators are bad? Have I now wrecked a new regulator by installing it with a bad one?

Any help would be appreciated.

Thanks

(I also have a 1996 Mercury 150HP V6 carbed outboard motor and Maxum 1900XR bowrider boat)

 

[hkeiner]

Re: PLEASE Help with overcharging issue

Nice choice on the boat and motor. Regarding the voltage regulators, I replaced both of mine at the same time and it solved the problem. I did this over two years ago, and the voltage has been OK since. I can't help you on what happens if you replace only one at a time, as I did not do that myself and I don't know enough to give an opinion.

 

[Thoroughbred]

Re: Same overcharging issue on a Merc 150HP (1996 carbed)

Re: Same overcharging issue on a Merc 150HP (1996 carbed)

My Merc 150 is also overcharging. While at idle the volt meter is usually 13-14 but while under way as it will eventually go up over 16 and will usually peg at some point. If running for some time the battery will leak acid into the battery box due to overcharging.

In an attempt to fix, I purchased one new regulator from local Merc dealer and replaced first one then the other regulator. No matter which was changed out the same overcharging condition would occur. Is it likely that both of the regulators are bad? Have I now wrecked a new regulator by installing it with a bad one?

Any help would be appreciated.

Thanks

(I also have a 1996 Mercury 150HP V6 carbed outboard motor and Maxum 1900XR bowrider boat)

Have you fixed your issue yet? I was thinking of buying one as well and hadn't done it yet but definitely won't now. For what it's worth I found the CDI's for just under $100 each.

 

[Thoroughbred]

Re: PLEASE Help with overcharging issue

I bought the CDI regulators

Sorry to re-visiting this issue but could wiring to a cowl switch cause the voltage regulator issue? I found a worn and corroded wire to the switch last year and I fixed it, now the cowl switch is acting up again so I am thinking there was more corrosion in the wire then I could see. I wanted to cut more off but was limited so I didn't. Looks like I need to find some wire and fish it through which is a pain in the butt.

When I run the motor at home in the water trough I can't get the amps to go up over 14 again even running up to 4,000 rpms. When it did before it blew the bilge and livewell fuses but that's it. I haven't switched out the regulators yet do to cost but an going on vacation in 2 weeks.

Any thoughts are greatly appreciated.

 

[Thoroughbred]

Re: PLEASE Help with overcharging issue

Replaced both VR with CDI's and it didn't go above just past 14 which is where it should be.

THANKS GUYS!!!!!

Now if I can get the not starting every once in a while issue solved I will be in heaven.