How do I jump a solenoid?

[Leosantanalg]

I m having this weird problem. The boat runs like a champ (5.7 mercruiser). When I stop in the middle of the lake, try to start the boat I hear a click and the starter doesn't crank, try again click, click... After few times, starts and runs perfectly! I ve been going out because it always starts after five or six tries but I m starting to get scared that it will not start next time. Most of people suggested a bad connection or a solenoid! My mecanic wants to change the starter!!! Tomorrow I will clean the main conectors at the battery and I would like to jump the solenoid! Is it hard? Does any one have a link to a diagram? Step by step maybe! Thanks to all in advance

 

[ande0652]

Re: How do I jump a solenoid?

That sounds like a bad connection or a solenoid going bad. The solenoid is pretty much a switch just like a light switch on the wall of your house. When you "flick" the switch on your wall, you are manually moving two metal poles together to make a complete circuit to light your light. A solenoid is the same thing except you have two smaller wires (starter switch) that go to an electrical coil in the solenoid. When power is applied to the smaller wires, a magnetic field causes a switch (two metal poles) to come together. The two larger wires (connected to the internal two metal poles) go from your battery to your starter motor. If you jump the two larger connections together you will put power directly from your battery to your starter.

You need to be careful doing this becuase the if the solenoid is the problem, as soon as you jump it, the starter motor will turn and possibly crank the motor. You also have to know that this is a very high current and it will spark as you begin to do it. It's low voltage (12v) so it won't shock you but will arc and could burn a small wire in half. When I find myself having to do this, I normally used a pair of needle nosed pliers to place across the larger poles. If this causes the starter motor to move, then replace the solenoid.

 

[Silvertip]

Re: How do I jump a solenoid?

There are a number of ways to do this.

1) Use a heavy screwdriver and short the two large posts on the solenoid being careful not to touch the metal case fo the starter. This is a very high-current approach and if you are timid, you will likely create serious arcing. Make that connection with authority.

2) Use a short piece of wire and jump the large terminal that has the POSITIVE battery cable on it, to the small terminal that has the wire from the ignition switch on it. (That would be the "S" terminal on the solenoid).

3) Use a jumper cable connected to the POSITIVE termnal of the battery. Touch the other end to the large terminal on the solenoid that feeds the starter. Keep in mind the ground cable connections need to be clean and tight for any of these tests to be valid.

 

[Chris1956]

Re: How do I jump a solenoid?

I had that very issue on my MerCruiser. I changed the keyswitch and slave solenoid to no avail. I eventually suspected it was the solenoid on the starter itself. I had been using rebuilt starters, and thought that part was never rebuilt. I never proved it though, an never got stuck on the water, although it did take a 1/2 hour to get the motor going one time.

 

[Leosantanalg]

Re: How do I jump a solenoid?

Ok I didn't jump the selenide yet because I didn't have a helper to turn the key on this morning but I was following the diagram troubleshooting below


http://forums.iboats.com/showthread.php?t=167035

And came to a new puzzle. On the diagram the starter solenoid has four screws (connections) and believe it or not mine only has two! Seems that everything is connected at one but one wire in the other!

The test light lit in all connections on the solenoid but I don't know how to move from this point! Any ideas???
Does it make sense?

Thanks to all. Has been a great help so far

 

[Don S]

Re: How do I jump a solenoid?

And came to a new puzzle. On the diagram the starter solenoid has four screws (connections) and believe it or not mine only has two!

Sounds like you have either an automotive starter, or a very cheap aftermarket starter. How about some engine info before we go further. Do you have a Mercruiser serial number for your engine?

On your starter, which ones from the picture below are you missing.

 

[achris]

Re: How do I jump a solenoid?

We need to get some clarity here... Are you referring to the starter solenoid (the one mounted to the starter motor itself) or the slave solenoid that switches power to the stater solenoid, which is mounted higher up on the engine?

And you don't need a second person there... Just leave the key in the ON position and do your jumping, the engine will start and run...

 

[mark1905]

Re: How do I jump a solenoid?

- Turn key to on position

- Take a screwdriver and touch it to both poles

- Engine starts



Rocket science, it's not.

 

[Leosantanalg]

Re: How do I jump a solenoid?

I believe I missing D and B. thanks and sorry for the delay!

 

[Leosantanalg]

Re: How do I jump a solenoid?

I checked the slave solenoid with a test light as my diagram instructed me and all the lights came as it should but when I move to test the starter solenoid there was only two screws on it. I was missing B and D from (Don S) picture above. ???? Should I just jump the slave solenoid and see what happens! Also another quick question, someone told me I can jump it with car jumping cables to avoid that crazy sparking!! Is that ok?

 

[Don S]

Re: How do I jump a solenoid?

I believe I missing D and B. thanks and sorry for the delay!

You better make sure, It can't be missing both of them or you have a real problem.

Post a picture of your starter and solenoid.

 

[Leosantanalg]

Re: How do I jump a solenoid?

Sure I will. Will be here tomorrow! Thanks again

 

[Leosantanalg]

Re: How do I jump a solenoid?

Couldn't get a pic of the starter without pulling it out! Too tight on compartment! However, I checked with a mirror and flash light and found out that there are four screws on the starter solenoid but everything is hooked to a single one (A). There is a single wire (yellow w red stripe) is hooked on (B) I believe! It could be (D). But for sure the other two have nothing on it! Are they jumping the starter solenoid?

The slave solenoid, I replaced today! Boat starts fine now. It was the problem..
Thanks for you guys I ve saved some $$$$$. .
Thanks everyone

 

[Grandad]

Re: How do I jump a solenoid?

Leo, just a quick note about manually jumping the solenoid. When you do this, you're also bypassing the neutral safety switch. Make sure you're in neutral when she turns over, particularly if you're in the water and the throttle is set high. - Grandad