Starter not fully engaging

[tomloans]

1B737378
FEB 2009
250 PRO XS L

Hello all,

I have noticed on the last several trips an odd noise from the engine upon first start up in the morning. This last time the background noise was very quiet and I heard it plainly. The starter is not fully engaging. This last time it happened twice. On the first and second start up. No issues the rest of the day.

Hence it appears to be getting worse.

Any recommendations before I pull the trigger on a new starter? Any recommendations on a reconditioned one? Should I just get a solenoid? Is it seperate from the starter? I haven't opened up the engine to see what the starter looks like yet. Maybe some bolts need tightening? Thank you.

Tom

[EuropeanAM]

Tom:

Make sure you load test your battery, and check for connection, cable or battery switch problems before investing in any parts.

Since it's hard to diagnose "sounds" by keyboard and monitor, it would probably be a good idea for you to observe the starter when cranking to see if there is indeed a failure of the drive gear to engage the flywheel (hard to tell for sure with cowling on).

There are two solenoids- one is the slave solenoid (on electrical plate), the other is the starter solenoid (mounted to and part of the starter). Make sure all connections there are tight, also.

The noise you are hearing- is it simply a spinning sound, grinding, whistle, or ???

[tomloans]

A quick light clatter. Have heard this before on other applications. In this case it does it on the first part of the crank and will engage after about one second of cranking. So it doesn't sit and spin disengaged where I would have to stop and crank again. All I have to do is crank for about 1 or 2 seconds of disengaged starter and then in jumps into the flywheel and starts the engine. This is the part that is odd to me. Usually it will not engage once it starts clattering and you would have to stop and turn the key again to start.

i will check connections. I will put a quick crank of the wrench on everything connected to it.

[lpugh]

Low voltage will cause the symptom you are describing, do a voltage drop test between the battery positive and the starter power connection that enters the starter motor while cranking, before the solonoid engages the starter circuit you should see full battery voltage, when engaged it should drop to one volt or less. The voltage read is the drop in the circuit and represents unwanted resistance. Do the same thing on the ground side. Total drop on both sides added together should not exceed 1.5 volts. The lower the better. If excessive then check individual component's, connection and cables the same way. I would be suspicious of a solonoid issue. The slave solonoid of this type is notorious for chattering as I think you are describing when voltage is to low, though not so common when used as a slave vs a main solenoid like Ford used to do.
Identify first where the noise is coming from solenoids, drive or starter motor
Insufient battery CA will over time will cause solenoids to fail in this manner as well as sometime sticking closed and it will not stop cranking

[Savage]

I would start by having the battery Load Tested, then go from there.

[tomloans]

The battery is a very large output battery and it is the correct size and parameters. The highest available in the market. I charge the battery before every use and top it off the night before. It only does it once or twice in the morning so I don't think it is the battery. If it were the battery I would think it would get worse through-out the day. I think it is either connections or the starter. I have not had a chance to run out and tighten all the connections yet but will do and take it out again and see what happens. But I will have the battery loaded to rule this out too.

[SilverFox579]

I would start by having the battery Load Tested, then go from there.

I agree...eliminate this variable first.

[Hyco Bass]

Might want to lube the bendix gear with a small dab of white lithium grease. I have no knowledge of you motor, but in my experience when the gear gets dry they can stall coming up and also hesitate when disengaging. Do not lube the starter teeth or the flywheel teeth. May not be an electrical problem.

[Savage]

Did you actually see the starter gear not fully engaging with the flywheel?

[tomloans]

No I didn't see it on the water Savage.

Last night I put a crimp on the solenoid wires. The large red one had some room for correction. I cranked a little on the main relay also. One small wire that was attached to the starter solenoid was completely loose. Not sure what this is wire is for but I tightened this.

I put the wires back onto the battery and cranked on them nice and tight. I turned the engine for a second to see if the starter will engage and it did perfectly. We will see what it does on the water. Will report back once I try it. Thank you for your help.

[tomloans]

Might want to lube the bendix gear with a small dab of white lithium grease. I have no knowledge of you motor, but in my experience when the gear gets dry they can stall coming up and also hesitate when disengaging. Do not lube the starter teeth or the flywheel teeth. May not be an electrical problem.

Hyco Bass, when i played with the gear it looked clean and loose. I will see if it was electric first and go from there. Will fill you in as soon as i get some feedback. thank you for your help.

[lpugh]

No I didn't see it on the water Savage.

Last night I put a crimp on the solenoid wires. The large red one had some room for correction. I cranked a little on the main relay also. One small wire that was attached to the starter solenoid was completely loose. Not sure what this is wire is for but I tightened this.

I put the wires back onto the battery and cranked on them nice and tight. I turned the engine for a second to see if the starter will engage and it did perfectly. We will see what it does on the water. Will report back once I try it. Thank you for your help.

That could and probably was your problem Tom. Good Job and saved you some cash to spend on tackle

[tomloans]

Leon what is that small wire. It looks like it is a ground of some type. It was so loose that the bolt that held it was about to come off.

[lpugh]

I asume you are refering to the solenoid on the starter. It excites the solenoid windings causing the iron core to move, which moves attached linkage that moves the starter drive up into the flywheel and at the same time it bridges the contacts to provide the high amperage current flow to the starter motor. Think of it as a amplifier for increasing current flow. The slave solenoid does the same thing for the main solenoid.. Because of all wiring switches as well as heat from hot soaks the main solenoid can have intermittent failure to operate without the slave to give a little boost
Early GM vehicles used to have this issue I described, installing a slave corrected the problem. This was smart on Mercurys part to do it this way assuring the starter would still crank the motor when a battery is down considerably.

[EuropeanAM]

No I didn't see it on the water Savage.

Last night I put a crimp on the solenoid wires. The large red one had some room for correction. I cranked a little on the main relay also. One small wire that was attached to the starter solenoid was completely loose. Not sure what this is wire is for but I tightened this.

I put the wires back onto the battery and cranked on them nice and tight. I turned the engine for a second to see if the starter will engage and it did perfectly. We will see what it does on the water. Will report back once I try it. Thank you for your help.

Not sure I understand how you crank on the main relay?

What color wire was this (and was it on the electrical plate or the starter-mounted solenoid)?

[tomloans]

LOL

"Not sure I understand how you crank on the main relay?

What color wire was this (and was it on the electrical plate or the starter-mounted solenoid)?"

I don't know all the technical names. :)

Cranked on the starter solenoid which wasn't tight and wasnt loose either. There are two small bolts on the solenoid and there is a small wire that is attached to one of these bolts that was completely loose.

The main relay below and to the left of the starter is what I also cranked on. And finally i put a quick crimp on the battery terminals.

Went out today and all worked perfectly. I think I just didn't have tight contacts.

[EuropeanAM]

Just guessing- but it was likely a yellow wire with red stripe, loose, on the starter solenoid (mounted to the starter)- that you tightened.

The other item you mentioned "cranking" (tightening terminal connections) on was likely the slave solenoid.

Thanks for the explanation- good catch- NOW you're "cranking".

[tomloans]

Just guessing- but it was likely a yellow wire with red stripe, loose, on the starter solenoid (mounted to the starter)- that you tightened.

The other item you mentioned "cranking" (tightening terminal connections) on was likely the slave solenoid.

Thanks for the explanation- good catch- NOW you're "cranking".

Thanks Don,

Just curious what that yellow with red wire is for?

[EuropeanAM]

Yellow w/red stripe is the "S" Terminal (originates at the keyswitch when you turn it to "Start"). Circuit travels through neutral safety switch, harness, connectors, a Slave Solenoid (which then provides clean power to the starter mounted solenoid to activate it).