Another battery charge thread

H

hundee r1

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Since installing a volt meter in my boat I've been able to confirm that my batteries are indeed not being charged.
Whilst the motor is running , the volt meter shows 11 volts, no matter what revs.

So after reading the sticky thread about a regulator swap, multimeter in hand I tested the system.

Disconnect the 2 yellow wires from the stator and tacho stops working, volt meter rises a tiny bit, and at 3000 rpm Im seeing AC 18+ volts at one of the yellow wires to.
Is it normal for the other one to show nothing?

Question is, I'm assuming its the normal symptoms for a faulty rectifier? It actually looks damaged with some black gunk oozing out :

Already looks after market yeh?


Secondly, If I don't install and adapt a universal regulator, can I retro fit this rectifier?:

Rectifier 50 AMP Heavy Duty Universal RM Chrysler Force Outboard | eBay

Im also curious, my loom has 2 yellow, 1 red and oddly 1 grey wire goin to the rectifier, I've only read of them having 2 yellow, 1 red, 1 black?
 
jerryjerry05

jerryjerry05

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Re: Another battery charge thread

Is that a burn spot on the rectifier?
You get the factory manual?
It has a section on testing the rectifier.
It's pages long and too much to type and has pics too.
I don't have a scanner that can do that either:(
Maybe someone will post something?
 
H

hundee r1

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Re: Another battery charge thread

Yep, burnt spot with black gunk oozing out internally. I will look at my manual once at work, have them electronically on work pc.
Common fail tho isnt it?
 
Frank Acampora

Frank Acampora

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Re: Another battery charge thread

If it has webbed feet, a bill, feathers, and looks like a duck, it probably is a duck! A burn mark on a rectifier is not normal! Replace it as a matter of course. The fuse must be good because you can start and run the engine.
 
H

hundee r1

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Re: Another battery charge thread

I hear ya mate, I was just more curious about the comparability of the one I linked. Il ring the seller and ask.
 
P

pnwboat

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Re: Another battery charge thread

The item on the link you posted is a full wave bridge rectifier. Your motor has a unit that is a combination rectifier/regulator. There is a difference. Your unit is supposed to regulate the output voltage to around 13.5 - 14.5 volts D.C. The full wave bridge rectifier does not regulate the output voltage. It will go as high as 16volts D.C. The older Force motors used the full wave bridge rectifier and starting sometime in the early 1990's they switched to the rectifier/regulator set up.

The full wave bridge rectifier will probably work, but you will not have any voltage regulation. Most folks that that make changes to their charging system go from a full wave bridge rectifier to the rectifier/regulator set up to limit the D.C. voltage output, not the opposite.

NOTE: Standard price for that full wave bridge rectifier here in the States is less than $5 U.S. at any electronics store.
 
H

hundee r1

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Re: Another battery charge thread

Wow, ok, making sense now. It's a 92 90hp and so therefore would have a rectifyer/regulator. I prefer to protect my expensive electronics so if indeed its faulty I will replace with another. Just have to double check that my testing method was indeed correct, I want to eliminate a bad stator aswell.

Thanx guys
 
P

pnwboat

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Re: Another battery charge thread

The charge winding in the stator should read about .6 OHMs. Very low resistance. Looks almost like a dead short. Tough to determine if you have an analog meter. A digital meter is easier to see.

Not sure if it makes any difference, but try checking the AC voltage output of the stator by measuring across the two yellow leads. I assume you were checking from ground to each yellow lead from your earlier statement about one lead having 18VAC and the other nothing. Having said that, if you are seeing 16 - 18 VAC output from your stator, it's probably good.
 
H

hundee r1

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Re: Another battery charge thread

Thanx again for your help mate, again one, of the great helpers on these boards.

Your right, I did just check the output of the stator by earthing out the meter on one probe and measuring the outputs ( yellow wires) with the other. (using a digital meter)

Explain what you mean "measuring across the two yellow leads"?Im not to good with sparks :(

The reason I also want to check the stator is cos during my motor rebuild I did notice that some black gunk has ozzed out of the stator as well and re solidified.

Chicken/ egg scenario, want to see what exactly needs replacing , then making sure whatever I replace doesn’t fail again because of another faulty part. Ideally I should just throw a new stator and regulator at it and be done with it, but Im pretty tight with $$$$ hahahaha.
Plus no cheap source for stators locally, as it is, the cheap universal reg/rec will have to come from you fine folks of the US, no one locally can tell me where to get one from.

Im at work today, so will troll my manuals looking for the test procedures.
Will also re read the sticky thread on this issue and see if Ive msissed something.

Thanx guys
 
P

pnwboat

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Re: Another battery charge thread

"Explain what you mean "measuring across the two yellow leads"?Im not to good with sparks :("

Place one probe one yellow lead and the other probe on the other yellow lead with the meter set on AC volts.



"The reason I also want to check the stator is cos during my motor rebuild I did notice that some black gunk has ozzed out of the stator as well and re solidified."

That is a sign that it may have gotten hot. As long as the resistance readings are within spec. I wouldn't worry too much.

It looks like your particular stator may have a low speed winding, and a high speed winding. Low speed winding should read 3250 - 3650 OHMs. High speed winding should be 75 - 90 OHMs. The stator wires are Blue and Red. Not sure which one is high or low speed. Disconnect the lead and measure between the lead and earth.
 
H

hundee r1

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Re: Another battery charge thread

Wow, thats some great info!! Last question, do I measure across the yellows whilst the motor is running? and if so, at what revs?

Same with the stator, I assume thats just static , with the motor not running nor ignition on.

wiring diagram fro my motor:
 
P

pnwboat

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Re: Another battery charge thread

Yes measure across the yellow wires with the engine running at least 2000 RPM's.

The diagram you attached looks to be the 1996 and later Mercury Thunderbolt CDM ignition system. Each coil has a 4 pin modular plug that connects it to the wiring harness. The stator wires are White/Green and Green/White.

From your picture of the regulator, I looks like you may have the earlier Mercury Thunderbolt ignition system in which each coil has two wires going to each coil attached with a small nut. This system utilizes a switch box to fire the coils. What color are the stator wires on your motor?

Forgot to mention that you check the stator with the engine off and the stator lead(s) disconnected. Put one probe on the stator lead, and earth the other probe.
 
H

hundee r1

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Re: Another battery charge thread

Yeh, OK, you are probably right cos I think the serial number on my motor starts with an 8. All my manuals are in PDF format, and the one I have for my actual year motor is only the Seloc rubbish. I assumed this cos it was the closest match to the parts Ive been investigating.
Id love to see the exact diagram of what mine actually is.
here is a pic of my motor if it helps, comfirmed as a 1992 vintage:



many thanks mate

edit, just had another look thru my manuals and came across this wiring diagram but says its for the 4 cyl 120hp.
The years match tho, as do the wires goin to the reg. I also cant see any other wires coming from the stator than the 2 yellows. I will have to have a closer look at mine tonite I think and see if I can find these blue and red wires you speak off:

 
H

hundee r1

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Re: Another battery charge thread

From the same Seloc manual here are what they say about testing the regulator:





testing the stator:



 
H

hundee r1

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Re: Another battery charge thread

pnwboat said:
"Explain what you mean "measuring across the two yellow leads"?Im not to good with sparks :("

Place one probe one yellow lead and the other probe on the other yellow lead with the meter set on AC volts.
Click to expand...

Ok, reading kept moving but it hovered around .5 ohms for most of the time (motor not running):




pnwboat said:
"The reason I also want to check the stator is cos during my motor rebuild I did notice that some black gunk has ozzed out of the stator as well and re solidified."

That is a sign that it may have gotten hot. As long as the resistance readings are within spec. I wouldn't worry too much.

It looks like your particular stator may have a low speed winding, and a high speed winding. Low speed winding should read 3250 - 3650 OHMs. High speed winding should be 75 - 90 OHMs. The stator wires are Blue and Red. Not sure which one is high or low speed. Disconnect the lead and measure between the lead and earth.
Click to expand...




 
H

hundee r1

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Re: Another battery charge thread

pnwboat said:
Yes measure across the yellow wires with the engine running at least 2000 RPM's.

The diagram you attached looks to be the 1996 and later Mercury Thunderbolt CDM ignition system. Each coil has a 4 pin modular plug that connects it to the wiring harness. The stator wires are White/Green and Green/White.

From your picture of the regulator, I looks like you may have the earlier Mercury Thunderbolt ignition system in which each coil has two wires going to each coil attached with a small nut. This system utilizes a switch box to fire the coils. What color are the stator wires on your motor?

Forgot to mention that you check the stator with the engine off and the stator lead(s) disconnected. Put one probe on the stator lead, and earth the other probe.
Click to expand...


You are 100% correct, out of the stator is 2 x yellow wires,1x blue, 1x red, also
picture pix showing the ignition type: (the 120hp diagram I posted still isn't correct)





100% right with your postings pnwboat!!
I will do the static test outlined by seloc on the reg at work in the morn with an electrical engineer, my meter is a bit complicated to understand by a simple man like myself,I will post up the rersults.
But from my photos above, stator seems to check out as ok against the Seloc manual across the 2 yellows and its close but slightly higher for the red and blue to your method, Il will have to run it again during daylight hrs just to double check, both your method and selocs during running.

many thanx!!
 
P

pnwboat

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Re: Another battery charge thread

Looks like the resistance measurements on your stator are just a tad on the high side but within tolerance. Not something to worry about at this time.

The static test on the regulator out-lined in the manual is OK, but the actual output test with the motor running at 2000 RPM's is the most accurate. If you have approx. 16 volts AC on the yellow wires with the engine running, but don't have 13.5 - 14.5 volts DC on the red wire of the regulator then the regulator is bad.

NOTE: The wiring diagram for your motor is at the top of page 5-69 in the Seloc manual.
 
R

RRitt

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Re: Another battery charge thread

I always subscribe to KISS principles when designing or repairing machines.

If you are measuring AC output on the yellow wires then assume the stator is good and move on. You can't measure any AC voltage if the stator has a broken winding. The stator is a winding of wire that spins inside a magnetic field. It creates electricity whenever it spins until the wire or magnet breaks. The faster it spins then the more voltage it puts out. When a wire breaks then the circuit is broken and you get no output. nothing, nada, zip, zilch.

so, KISS.
disconnect battery and measure output. if under 13V then take battery out of boat and charge in garage. Let sit for a few hours after charging and measure again. If still too low then you have bad battery that is artificially holding down voltage (and probably caused that burn spot). If battery tests fine then throw a $30 regulator on engine and measure the output again. By now your problem is probably fixed.
 
H

hundee r1

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Re: Another battery charge thread

Thanx Richard for you input aswell.

the batterries have both been load tested and take full charge well.

Static testing of the reg failed in all instances of the Seloc test except for the second one.

I will double check the output at the reg when I have the motor running again, just to be well and truelly convinced but I will spend the next couple days trying to find a replacement locally, if not will then look inoto getting one sent over.

Will just have to comfirm I can get one with teh tacho output inbuilt, else I believe I may have to bypass the reg with the tach wire and piggy back it to one of the yellows?
 
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