Merc 1250 wiont start.

[captainpierre]

Hi Guys,

I have an old merc 1250, its been running like a champ since I bought it. I went and launched the other day, hop in and turn the key and get nothing but a click.

Ok, so thats embarrassing. Sorry guys, give me a sec to get my boat out of the water!

I tried switching out the battery with my car's still nothing but a single click when i turn the key.

Was going to try rope starting it, but am unsure how. It would be nice to know that it is just the starter. So while looking around the engine I spot some corrosion on some ground wires, and on the wire from master motor control plug to a wiring block that has wires that continue up to the red thingee at the top of the engine (that spins when the starter is working. (has timing markings on the side of it)). - these wires have brittle insulation that comes right off if handled at all, and cracks in the insulation where you can see oxidized copper (green) in the cracks

I'm guessing that you can tell from my liberal use of the word thingee that I am hardly a competent mechanic.

I guess my question is two part... can I just pull the starter out and touch it to a battery and if it starts spinning is it good?

Is it possible that the wire corrosion is the problem? The boat was just working fine a month ago. If so what guage wire should I use to rewire the harness?

Any advice you can give is much appreciated.

Thanks.

 

[hoosiercaver1]

Re: Merc 1250 wiont start.

When I rewired mine, I used 12awg thhn copper for all but the red power lead to the rectifier and switch box. I used 10 awg for that cause it was a bigger wire originally. It does sound like the wiring could be a part of ur problem, but I know mine still ran with the brittle cracked and exposed wiring, but I wanted to clean it up. I know u defineately need a good ground path for that starter to work. It's pulling a lot of amps.

 

[Georgesalmon]

Re: Merc 1250 wiont start.

You don't have to pull the starter out. Just use a batt jumper cable from pos on batt and touch the starter terminal. If it spins it should be OK. Then check the starter solonoid. Clean all the connections to the starter and solonoid. Take em off and use electronic cleaner a brush and put them back on and try it. I guess you should replace the wires. I have a 79 merc and I cleaned the oil off of the cracked and broken insulation with brake cleaner, then put three layers of liquid elect tape on them. Letting dry between each coat. As i said it not the best solution but I did that three years ago and the liquid tape is still holding up.

 

[captainpierre]

Re: Merc 1250 wiont start.

You don't have to pull the starter out. Just use a batt jumper cable from pos on batt and touch the starter terminal. If it spins it should be OK. Then check the starter solonoid. Clean all the connections to the starter and solonoid. Take em off and use electronic cleaner a brush and put them back on and try it. I guess you should replace the wires. I have a 79 merc and I cleaned the oil off of the cracked and broken insulation with brake cleaner, then put three layers of liquid elect tape on them. Letting dry between each coat. As i said it not the best solution but I did that three years ago and the liquid tape is still holding up.

Thanks!

The starter spins just fine, ordering a new harness and solenoid right now!

For any Merc 1250 owners...

Starter Solenoid
25661 Merc part number
ARCO SW661

Internal Wire Harness
48150 Merc part number
CDI Electronics 414-2770
http://www.cdielectronics.com/InstallSheet/414-2770.pdf