83 Merc 5.7 odd starter question

[BuzzM]

Since ownership, my engine starter operated a bit differently than I expected. When I turn the ignition key, it would turn over fine, briskly & engaged; but wouldn't fire up & actually start the engine until I released the key. Then it would run fine.
A mechanic a couple of years ago said that I needed a wire connected from the starter to a post on the coil to " fix" this problem. He said the bendix was probably not releasing. Since then, it starts like a car.. truns over, fires up, then I simply release the key.
Now, my current mechanic said that was nonsense and I could damage the starter system by leaving the wire in place.
Additionally, I am wondering if this wire contributes to my corrosion issues.
Any thoughts?

 

[Bondo]

Re: 83 Merc 5.7 odd starter question

Go back to your Old Mechanic,.........

That Ign. wire Needs to be there...........
And,....
It's got Nothing to do with your Corrosion Issues......

 

[Don S]

Re: 83 Merc 5.7 odd starter question

If your engine and distributor are original, then you should have the Thunderbolt electronic ignition and won't have that wire to the starter/coil.
What you might try is checking the voltage at the coil + terminal and the ignition terminal on the ignition switch while in the cranking position and see if you have power to both places. If not, you may just need an ignition switch.
Some ignition switchs were designed to not power the ignition side during starting because the starter wire your old mechanic mentioned put power to the POINTS on the old point type ignition and bypassed the resistor wire or ballast resistor used on those systems.

 

[BuzzM]

Re: 83 Merc 5.7 odd starter question

Thanks. It has the original Thunderbolt system. I replaced the ignition switch in March, but never thought to remove this wire. This 1983 Sunrunner 245 was a slip queen with 78 hrs on it when I bought it in 2001 from an older gent to lived on it occasionaly.
I'll perform the voltage check as suggested.
Always learing ... the hard part is remembering.

 

[WillyBWright]

Re: 83 Merc 5.7 odd starter question

Did you get an automotive ignition switch? That would explain your problem Get one from a marine dealer, or one from NAPA specifically for marine use. They are also available here on iboats. Besides your current problem that can be fixed with that jumper wire between the small stud opposite the small Start stud on the starter solenoid, you'll find that it won't hold-up to the elements. Rain and humidity will kill it in a matter of months. Marine switches are made to tolerate the elements much better.

 

[Don S]

Re: 83 Merc 5.7 odd starter question

I replaced the ignition switch in March, but never thought to remove this wire.

What do you mean you never thought to remove this wire?
What Wire? ? ? ?

 

[Bondo]

Re: 83 Merc 5.7 odd starter question

A mechanic a couple of years ago said that I needed a wire connected from the starter to a post on the coil to " fix" this problem.

I believe we're talking about the Starter's Ignition wire,.....
the 1 from the Little Stud on the Starter that goes to the Coil,......
If it was a points Ignition..........The Resistor By-pass Wire.......

 

[BuzzM]

Re: 83 Merc 5.7 odd starter question

The wire that I am talking about was added about 2 years after I got the boat. While having the carb reinstalled after a rebuild, the mechanic said that this wire was necessary or my starter would eventually be ruined. I can't find it on any diagrams for a thunderbolt system. I do need to replaced the " replaced " switch with a CORRECT one for this application marine switch as recommended, however.

 

[Don S]

Re: 83 Merc 5.7 odd starter question

The reason you can't find that wire on any diagram is because it's not supposed to be there. You "Mechanic" didn't do anything buy try to find a way to "Make It Work" instead of finding the actual problem and fixing it.
Here is an ignition switch that will work

http://www.iboats.com/mall/?keyword...=094629584&list_time=1166975401&view_id=47124

 

[BuzzM]

Re: 83 Merc 5.7 odd starter question

Thank you very much. I hope you & the rest of the forum's experienced " advisors " realize what a value you provide to those of us who continue to learn about these machines. We appreciate your patience in helping all of us not only save a few dollars, but gain an understanding of marine mechanics.
thx