1980 70hp charging system

17rogue70

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i think my chargeing system maybe on the fritz.how can i test it to find out?:eek: all other problems are ironed out thanks to the this awesome forum and its mechanics. thank you guys for everything you do for us do it yourselfers:D:D
 

bktheking

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Re: 1980 70hp charging system

Measure the voltage on the battery when its running with a meter and report back.
 

17rogue70

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Re: 1980 70hp charging system

easy on me fellas,im not an elect guru:eek:.correct me if im wrong ,but the rec/reg should show current on 1 leg (yellow) wire but not the other(yellow/grey) correct?visa/versa, that means the regulator is good right? if im correct my stator is bad,yes? does it harm anything to run with bad stator? i ask this question because i dont know how long it has been this way and i have about 6 outings with this boat as i recently aquired .new battery so i dont know if it was charging when batt was replaced or not. my last time out ,round trip was approx 18 miles .hope i havent damaged anything else.:confused::( thank you for all responses in advance. elect is not my strong point,so i apologize for all the dumb questions.
 

bktheking

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Re: 1980 70hp charging system

This motor doesn't have a regulator, just a rectifier which converts AC supplied by the stator to DC...........your stator may be ok and the rectifier bad. You will need to disconnect the rectifier from the terminal block and test it. You don't test it will running, you test the part in your hand with a meter, the results will tell us if you have a blown diode in the rectifier.

As per Joe Reeves in instructions:

Remove the rectifier wires from the terminal block. Using a ohm meter, connect the black lead of the ohm meter to the rectifier base (ground), then one by one, connect the red lead of the ohm meter to the yellow, yellow/gray,
then the red wire (some rectifiers may also have a fourth yellow/blue wire. If so connect to that also). Now, reverse the ohm meter leads and check those same wires again. You should get a reading in one direction, and none at all in the other direction.

Now, connect the black lead of the ohm meter to the red wire. One by one, connect the red lead of the ohm meter to the yellow, yellow/gray, and if present, the yellow/blue wire. Then reverse the leads, checking the wires again.
Once more, you should get a reading in one direction and none in the other.

Note that the reading obtained from the red rectifier wire will be lower then what is obtained from the other wires.

Any deviation from the "Reading", "No Reading" as above indicates a faulty rectifier. Note that a rectifier will not tolerate reverse polarity.
 

17rogue70

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Re: 1980 70hp charging system

these are the results as follows;

blk to rec base

red to yell 0
red to yell/grey 0
red to red 0

red to rec base

blk to yell 100 ohm
blk to yell/grey 100 ohm
blk to red 100 ohm

blk to rec red

red to yell 100 ohm
red to yell/grey 100 ohm

red to rec base

blk to yell 2 ohm
blk to yell/grey 2 ohm


does this make any sense?:confused::confused:
electrical freaks me out badly.

thank you very much for such a quick reply and answers.
 

17rogue70

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Re: 1980 70hp charging system

thanks for the answers so quickly. well, i have no guages or instrumentation,except a fishfinder.when i use my tilt and trim it sometimes flashes 11.5/11.6volts on the screen,but seems to have plenty of cranking power.sometimes at rest while fishing with f.f on it will flash 11.5/11.6,which leads me to think it isnt charging.havent tested voltage at batt while running yet.::redface:again thank you for your time and patience.
 

bktheking

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Re: 1980 70hp charging system

Use a meter, I've done the finder vs the meter and the meter is more accurate, the finder causes a drop in voltage whereas a multimeter doesn't but you should still see above 12.5 on the FF while underway. Since it's an unregulated system you should see 14-16 volts while under way. Seeing 11.5 volts while off and operating t&t and finders will put a load on the battery dropping it to 12V or less. The telltale that my rectifier was blown was the starting power. I put a new battery in and on the 8th or so outing it was dead again so something wasn't working, I had a blown diode in my rectifier.
 

17rogue70

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Re: 1980 70hp charging system

this was probably my 6th trip but like i said the cranking power seemed to be good and strong. and the battery is new by 2-3 weeks . i need a voltage meter correct? check before starting and whike running? i apologizefor all the questions but i dont want to get stranded out on the water. most of all i want everything as close to 100% as possible.


thanks for all the advice,
mike in fla.
 

bktheking

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Re: 1980 70hp charging system

While running is what you want and a multimeter should do DCV if you have one, you measured ohms or what that just with an ohmmeter?
 

17rogue70

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Re: 1980 70hp charging system

that was just an ohm meter.again thanks for all the help.if you are ever down this way i owe you a cold one or two.ill def let you know what i find out as soon as i know myself. probably tomm afternoon.
 

17rogue70

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Re: 1980 70hp charging system

results on the dcv before starting were 12.31 v. while running were 12.23v
without any increase during acceleration process. again bktheking i am most greatful for all of your answers and replies. you guys that offer free info cant possibly realise what it does mean to some people.:D again thank you.
 

bktheking

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Re: 1980 70hp charging system

Your wlcome, lord knows I`ve had my share of puzzles and the guys on iboats have been awesome, I believe in Karma.

It`s not charging, same results as I got when my rectifier was blown, should be more like 14+ volts. Couple of checks , there should be 2 ground wires coming from the stator being held to the powerhead by bolts, clean the grounding surface and retry also try running a ground wire to the housing of the rectifier and see if you get more volts, trying everything possible before digging into the stator for possible replacement ($200+). Also check all the wiring in going to the stator from the terminal block, may just be a broken wire. Use a multimeter and check from one end of the other using the continuity setting if it has it (should beep at you)
 

17rogue70

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Re: 1980 70hp charging system

stator is under the flywheel? what are the wire colors? ill try grnd to rec base now
 

bktheking

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Re: 1980 70hp charging system

Yup ,under the flywheel.Give me 5 to find it in my manual
 

bktheking

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Re: 1980 70hp charging system

Here is the stator test for your motor:

1. Pull the neg cable
2. Set your ohm meter on high scale
3.Disconnect the yellow and yellow/gray leads from the stator (not the rect) from the term block
4.Connect ohm meter black lead to ground Connect the red to each stator lead and observe, you should get infinity on both leads, anything else indicates a short to ground.
5. Set the meter on low scale and connect one lead to yellow and the other to yellow/gray. Thereading should be 0.7-1.3 on your motor. If the meter reads infinity the stator windings are open. If the readings aren't within spec replace the stator.
 

17rogue70

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Re: 1980 70hp charging system

cleaned all grounds that i new for surebut no dice. i even tried the grnd jumper from rec to block to no dice either.just dunt know about the stator wires .thanks bk you are the king.:D
 

bktheking

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Re: 1980 70hp charging system

Check my last post, I wrote you the stator check procedure, sounds like it might be the culprit.... :(
 

17rogue70

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Re: 1980 70hp charging system

have ti try stator tomm,its getting dark here in fla now:mad:. again thanks a million bk, i was afraid of that
 

bktheking

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Re: 1980 70hp charging system

have ti try stator tomm,its getting dark here in fla now:mad:. again thanks a million bk

No rush, better to get it figured out without spending money , money is well spent on beer , not replacing parts that don't need to be.
 
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