1972 mercury 80hp starting issues, please help me save my baby.

GA_Boater

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Yours sounds exactly like mine did last year. It was the starter and I tried all the tricks. Even tore apart the solenoid/starter and cleaned the guts, along with all the connections. It was still the starter. Jumped from the battery directly to the starter and guess what? It was still the starter.

Try all the suggestions, but start looking for, you got it - a starter.
 

GA_Boater

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Got your motor serial number? No guessing then.
 

GA_Boater

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

New Starter Mercury Mariner Outboard 115 135 HP 1970 1972 MJL4002 MJL4002A | eBay

would this be an appropriate replacement? I am not that familiar with the aftermarket parts and or quality of them. Thanks for any suggestions.

No, you have an 80 horse motor, not a 115-135 HP. The Merc part no. is 50-58788A 3. Search for an aftermarket starter with the equivalent Merc P/N.

Here: Premium Outboard Starter - Sierra

And here: MES, Mercury Marine, Mariner Replacement Outboard Starter 5377 - Arco

iboats will price match if you find a better price.
 

Timestep

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

The serial number is irrelevant ?

It's the battery, the wires/joints or the starter surely ? (in that order)

Dave
 

GA_Boater

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Why is the S/N irrelevant?
 

Fed

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

I'd check the voltage between the starter positive stud & the starter outer case.
 

colinwalsh

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

The serial number is irrelevant ?

It's the battery, the wires/joints or the starter surely ? (in that order)

Dave

prior to my attempt to turn the motor over I noticed a burned up wire, melted outer casing. I flipped the key over and it started to smoke on the faulty wire. I noticed this wire goes directly to where the outer wiring harness connects to. Is this wire able to be replaced by it self? it looks like there is a whole system of wires that are connected to the outer wiring harness. I apologize for my non advanced boat descriptions.

from what I read in the manual it looks like the wire is connected to the electrical harness from the starter if I am correct?

thanks for any any all advice, it is truly appreciated

Colin
 

GA_Boater

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

The first mention of burned up wires. Anything else we should be aware of?
 

eggs712

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Have you tried directly jumping the battery to the starter? That will tell you immediately if the starter is good or not.
 

colinwalsh

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Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

Re: WHY WILL MY OUTBOARD NOT TURN OVER? 1972 80hp merc

The first mention of burned up wires. Anything else we should be aware of?

I had just noticed the burned wire when I was about to take off the starter. It was late and after work so I didnt want to mess with it in the dark. Tomorrow I am working a half day and will post photos of the wire where it seems to be smoking out of.

thanks again for all the help.
 

colinwalsh

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1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

I replaced all of the internal wiring harness wires with a new unit via partspak.com (thanks guys) and I still have the issue of the motor not turing over. I also took the starter off and inspected it. all points (4) were making good contact with average wear for a 1972, this starter looks to be aftermarket. I was told previously that it is the starter. I am now thinking that it could be the trigger?

well thats the issue short and sweet. thanks for any help guys. cant wait to see her back in action!

-Colin



:confused:
 

merc850

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Re: 1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

Re: 1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

Are you lifting the cold start lever (small black one on the control box) to upright position? It sounds like low idle speed that can be adjusted by turning the screw in front of distributor. Do you have a tach?
 

colinwalsh

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Re: 1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

Re: 1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

Are you lifting the cold start lever (small black one on the control box) to upright position? It sounds like low idle speed that can be adjusted by turning the screw in front of distributor. Do you have a tach?

Thank you for the feedback, I will try that when I go to my boat tomorrow and let you know. I do not have a tach hooked up.

Thanks again

-Colin
 

merc850

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Re: 1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

Re: 1972 mercury 800 ISSUES----VIDEO INCLUDED_what is preventing motor to idle?

It should idle at 600 rpm, the idle screws in the carbs have to be set running in forward moving in water on a warm engine. Start set them 1-1/2 turns out then set them for smooth running but not too lean.
 

colinwalsh

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mercury 80 hp turning over but will not fire- VIDEO INCLUDED

mercury 80 hp turning over but will not fire- VIDEO INCLUDED

not sure why she wont turn over. I replaced the internal wiring harness because it was really nasty and still have the same issue.

 

GA_Boater

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Re: mercury 80 hp turning over but will not fire- VIDEO INCLUDED

Re: mercury 80 hp turning over but will not fire- VIDEO INCLUDED

This little saga began on December 18th and this is the sixth thread you've started. Do you know why it isn't fixed yet? Because instead of following the given advice, you drop it and start a new thread.

I got into the one you started on April 4th and gave some possibly erroneous advice because I didn't have the history in one thread and you dropped that one too. On December 28th you were asked to check your timing belt. Did you, you never replied? But you keep starting new threads.

Stop starting new threads and answer the questions! And read the forum rules, especially:

11. Please do not post multiple threads in multiple forums about a single problem. This is confusing to those trying to help you. Multiple threads in the same forum about the same issue are also confusing. If you want help fast, one thread in the most closely related forum is the best way to get it.

You keep posting multiple times in the same forum. Stick to one thread if you want help. We are trying to help you, but you aren't helping us.
 

achris

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Re: 1972 mercury 80hp starting issues, please help me save my baby.

Without reading all of them I have merged all 6 threads together. Please use the same thread for the same problem, and not keep starting new ones. It confusing for everybody, including you....

Chris........
 
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colinwalsh

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Re: mercury 80 hp turning over but will not fire- VIDEO INCLUDED

Re: mercury 80 hp turning over but will not fire- VIDEO INCLUDED

not sure why she wont turn over. I replaced the internal wiring harness because it was really nasty and still have the same issue.


Ok, well I apologize for starting new threads I thought that it would get different attention from different people but I was wrong. I have done everything mentioned accept buying a new trigger, which is a little out of my price range currently but I will see what I can do. thanks for all the help guys.

-Colin
 
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