Voltage to high?

[redleo]

I have a 1977 Mercury 150 V6,have just fitted a volt gauge and found that it is reading 16volts at 800rpm and above,have checked reading with multimeter at battery and is the same.
Is this normal

 

[arsenalpsu]

Re: Voltage to high?

16v is fine, but that's only at 800 RPM, what are you when your at WOT or cursing? You can just turn on some lights when cursing, just remember to turn them off...or you can spend some $$ and add a regulator to your system

 

[j_martin]

Re: Voltage to high?

I have a 1977 Mercury 150 V6,have just fitted a volt gauge and found that it is reading 16volts at 800rpm and above,have checked reading with multimeter at battery and is the same.
Is this normal

That's normal, but you need some education on an unregulated system. It's been beat to death here, so do some research using the search function.

Welcome.
John

 

[Dukedog]

Re: Voltage to high?

Something don't add up. '77 should have been a 9 amp stator and flywheel. Tha 16 hadn't come out yet............

 

[j_martin]

Re: Voltage to high?

Something don't add up. '77 should have been a 9 amp stator and flywheel. Tha 16 hadn't come out yet............

Huh?

 

[Dukedog]

Re: Voltage to high?

Huh?

And your point?

So just maybe its been changed. But back to tha problem. We have seen some problems with tha 16 and no regulator lately. Seems that some of tha NEWER electronics have a voltage protection that shuts 'em down at 15/16 volts. We have had to put reglators on 2 boats in tha last two weeks 'cause of this. Just something you might think about if ya got or gettin' new stuff in tha future..................

 

[sschefer]

Re: Voltage to high?

And your point?

So just maybe its been changed. But back to tha problem. We have seen some problems with tha 16 and no regulator lately. Seems that some of tha NEWER electronics have a voltage protection that shuts 'em down at 15/16 volts. We have had to put reglators on 2 boats in tha last two weeks 'cause of this. Just something you might think about if ya got or gettin' new stuff in tha future..................

Agree... Regulator/Rectifiers aint cheap but neither are good batteries. I use battery isolators also.

 

[CharlieB]

Re: Voltage to high?

No one asked an important question,

How OLD is the battery?

Generally, on a battery that is in good shape, the battery is the voltage limiter in the NON-regulated system, voltage will rise to the maximum that the battery will allow.

As a battery ages that upper voltage limit rises and you start noticing the higher voltages. Usually this isn't a problem until the battery starts failing to HOLD a charge and begins to fail under starter load.

The biggest drawback with the non-regulated systems is many owners fail to check battery water levels until they fall too low and the upper ends of the plates dry and die.

 

[j_martin]

Re: Voltage to high?

And your point?

Either 9 amp or 16 amp system is unregulated, and will put out up to 90 volts if the battery load is missing. So what was your point about 9 amp or 16 amp system?

 

[Dukedog]

Re: Voltage to high?

Some production 16's (later years, '86 up) were regulated. All 16's on tha Hi Po motors(2.0,2.4,2.5's) were regulated. It came out as a 9 so if it was changed to a 16 how or what else was done?

Good point Charlie. First thing we checked on tha 2 cases I refered to. They were fine. After tha added regulator they dropped to 13/14 volts........

 

[j_martin]

Re: Voltage to high?

Some production 16's (later years, '86 up) were regulated. All 16's on tha Hi Po motors(2.0,2.4,2.5's) were regulated. It came out as a 9 so if it was changed to a 16 how or what else was done?

Good point Charlie. First thing we checked on tha 2 cases I refered to. They were fine. After tha added regulator they dropped to 13/14 volts........

This is obviously an unregulated 16 amp common on the fishing motors of that era.

Of course the pulse mode regulator refines the product, but it was not available on that motor. The regulator they first put on was a zener clamping affair that had a bad habit of catching fire. It's NLA. If you maintain your battery, it's not needed. You can splice one in on any system if you wish.

 

[redleo]

Re: Voltage to high?

Thanks great info