starter??

[scottyisback44]

My motor is a 73 merc 65 hp. It will not turn over by the key when the plugs are in. Take the plugs out and it spins over strong. Is it the starter or cables or connections? And whats the best way to figure out what it is?

 

[sutor623]

Re: starter??

Does the starter gear try to engage when you turn the key? Does it just spin? When you say plugs out, are you taking the spark plugs out and testing it?

 

[sutor623]

Re: starter??

Did you check your main battery wires and terminals for corrosion? How old is the battery? Many people point fingers at the starter when the battery cables are in shotty shape.

 

[scottyisback44]

Re: starter??

The battery is brand new. 625 cca. I took the plugs out to see if the starter would turn the motor over with no compression. And the starter turns the motor over.

 

[sutor623]

Re: starter??

Okay well how do the battery wires look? Many times corrosion gets deep inside the insulation and it is hard to tell that the wire is in fact corroded. If you have the original wire harness I bet this is the case. I have a '67 Merc and needed to cut back 3-4 foot of wire and bar splice in some fresh 6 gauge.

 

[sutor623]

Re: starter??

You can go back a few inches from the terminals and cut a little slice of the insulation. If the wire is green then you need to change it. If it is not, tape up the splice. Also check all the wires/connection to starter and solenoid.

 

[scottyisback44]

Re: starter??

Guess i can start there. Im baffled with this problem.

 

[sutor623]

Re: starter??

Dont be too baffled. The relief of strain on the starter motor by pulling the plugs is giving it an easier time turning the motor. You seem to have a big voltage drop from the battery to the starter. Trust me just check the cables. If they are not corroded I will put a sock in it.

 

[scottyisback44]

Re: starter??

Any generic battery cable will work right? As long as its 6 guage. I shouldn't need engine specific cables, correct??

 

[sutor623]

Re: starter??

Well you SHOULD use tinned wire because it will prolong the corrosion process. I bought two 6' sections of 6ga. wire from the auto parts store, and 6ga. bar splice clamps from lowes to connect the wires. I cut the wire back until I saw no more corrosion and then spliced it. So mine is not tinned, but it has been over a year and no issues. I also keep the boat tarped in the front yard all year. Have you already verified that there is corrosion?

 

[sutor623]

Re: starter??

Your other option is a new external wire harness. Mine for my '67 Merc is $400, so I took the bar splice route.

 

[scottyisback44]

Re: starter??

Haven't verified corrosion yet. Was going to go to the auto parts store and run new cables to eliminate the splicing. I only plan on keeping this boat for this year so tinned isnt a concern.

 

[sutor623]

Re: starter??

How are you going to eliminate the splicing? You will need to splice the new wires to the wiring harness.

 

[CharlieB]

Re: starter??

Before spending a dime do a few simple tests.

Check battery voltage at the starter relay/positive battery cable then check again during cranking, check cranking voltage with and without spark plugs. How much voltage drop do you see in the three tests?

Grab your trusty battery jumper cables and jump directly from the battery top the starter, does it crank now? With the spark plugs in?

Poor connections, poor cables will not carry enough current and the voltage will drop. If your jumper cables crank fine this verifies the poor connections/cables.

If it will NOT crank well with the jumper cables you may want to look inside the starter.

 

[scottyisback44]

Re: starter??

Jumping the starter directly from the battery to the starter with jumper cables wouldn't spin the starter. All it did was get hot. Guess its time for a new starter.

 

[sutor623]

Re: starter??

Jumping the starter directly from the battery to the starter with jumper cables wouldn't spin the starter. All it did was get hot. Guess its time for a new starter.

Yup.

 

[scottyisback44]

Re: starter??

Thanks everyone for all the help

 

[scottyisback44]

Re: starter??

Put a used starter on it today. Pushed the choke in. Motor fired right up. Sweet jesus it runs!!!!

 

[sutor623]

Re: starter??

Tite!!