2009 yamaha 115 four stroke starter relay replace question

kentrx1

Seaman
Joined
Jul 15, 2005
Messages
57
getting one click with no voltage drop at starter. happens randomly, usually at first start up of day if at all. usually can turn switch mutiple times----sometimes seems like a 100---then it magically cures itself for the rest of the day------or maybe many days. from what i have read it seems like the starter relay is a common culprit and pretty cheap to replace. my question is how hard is it to get to and replace. it is on a pontoon and i am wondering if it is simple enough to do while in the water at shore/dock or should i put it back on the trailer to work on it? thanks for any help!
 

boscoe99

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Aug 22, 2013
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I am not understanding the switch being turned as the cure as having anything whatsoever to do the starter motor relay.
 

99yam40

Fleet Admiral
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Sep 7, 2008
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9,085
is a starter replay the same as a starter solenoid?
usually the high current contacts get pitted/burned and do not make good contact from time to time.
or a bad connection somewhere in the battery system arcs and makes good contact for awhile.

I like working on things on solid ground so if I drop something I have a chance of finding it
 

kentrx1

Seaman
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Jul 15, 2005
Messages
57
I am not understanding the switch being turned as the cure as having anything whatsoever to do the starter motor relay.
My understanding is the points get burned and continuing to engage eventually makes enough contact to fire starter.
 

boscoe99

Lieutenant Commander
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Aug 22, 2013
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OK. I think I got it.

The ignition/start switch has internal contacts. The starter relay has internal contacts. The starter motor relay (aka solenoid) has internal contacts. These contacts are normally open. They are closed to allow electrical current to pass across them.

Neither part is particularly difficult to replace. Some trouble shooting is needed to determine where the problem lies but if one wants to simple remove and replace a part you can certainly do so.

One thing you might want to do is to disconnect, clean and reattached all electrical connectors related to the starter system.

 

brodmann

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Jun 17, 2008
Messages
426
Diagnosis is pretty simple. A starter solenoid or relay allows you to use a small amount of voltage through your ignition switch by using low voltage, basically a coil of wire that when voltage is sent through it, it becomes a magnet and draws a plate toward it to make a connection. Use a volt meter to check voltage at the starter. You'll need a helper, but the starter should have either one or two wires going to it. If it has two, they'll be black and red. If it only has one it will be red, and instead of a large black wire, the started is grounded by being mounted to the engine. Place the positive lead of the meter to the red wire, and connect the black wire of the meter to either the black wire on the starter of the a bolt somewhere on the motor. when the key is turned, if you have voltage at the starter, then the starter is bad. If you don't have voltage at the starter when the key is turned to crank, you either have a bad solenoid or relay, or it could be the ignition key switch.
 

wmgeorge

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Jun 6, 2023
Messages
65
Is that starter relay / solenoid something that can be carefully replaced while the boat is in the water? I know disconnect the battery. This is on a F40 year 2007.
 

brodmann

Chief Petty Officer
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Jun 17, 2008
Messages
426
Okay, I'll give you a much simpler way to diagnose the problem before you start replacing parts that may/may not be bad. The next time you try to start the motor and it won't turn over, turn and hold the key and have someone tap the starter lightly with a hammer! If the starter works, you have a bad starter. I've used that test for 50 years. Never fails. I don't know if you have a relay or a solenoid, so I can't tell you how easily you can replace the part. If it's a relay, it simply plugs in. If it's a solenoid there will be two small wires and two larger wires. If you use a screwdriver or a piece of wire to make a connection between the two larger wired and the starter turns, then your solenoid is the problem. Again, I don't know what you have, and I'm not looking into your motor to figure that out. You'll need to do just a little bit of the digging into this yourself.
 
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