New starter motor faulty?

[Llewelyn82]

Got a bit of a head scratcher... I bought a high torque starter from SJ to replace my original starter motor as it was basically on it's way out. Anyway I've fitted it but since then the starter motor relay (not the solenoid), clicks once and thats it. I don't get any joy from the solenoid at all.

I've verified:

Good engine ground

A nice healthy voltage directly to the starter motor

Momentary trigger voltage from the starter relay to the white/red signal cable which connects to the starter solneoid seems to be there

I don't really want to have to remove it and then post back to SJ, and wait for a replacement etc so I'm hoping it's operator error! Anything else worth checking?

The only thing I haven't tried yet is applying 12v direct from the battery to the solenoid exciter terminal. Will report back tomorrow morning on this. Any pointers in the meantime would be appreciated

[Sparky]

Voltage might be there, but what about current? Do you know your battery's good?  Yes, put 12v direct to solenoid.  If that doesn't work, try and get a jump lead on the starter feed for a quick jolt.

[Llewelyn82]

13 minutes ago, Sparky said:

Voltage might be there, but what about current? Do you know your battery's good?  Yes, put 12v direct to solenoid.  If that doesn't work, try and get a jump lead on the starter feed for a quick jolt.

Thanks sparky... The battery is fully charged and new-ish so should be ok. I’m getting 12.5v ish at the starter feed although haven’t checked the current.

I’m not sure I understand your comment though - isn’t putting a jump lead on the solenoid and starter feed the same thing? I’ve already got voltage at the starter, which is permanent  

[Barrykearley]

Check the voltage at the same time as turning the key.

if the battery doesn’t have the capacity to deliver the current required to turn the starter you will see the voltage drop considerably. For the few hours it’ll take - chuck a charger on it and see

[silverfrost]

Also, check the pos battery cable to terminal,,  Very rare but can happen,  the thick pos wire snaps at the terminal meeting point, still provides a current reading as the broken bits of thick battery cable slighty touch, but not enough to provide enough current for cranking.  

[Llewelyn82]

Cheers guys! 

I’ve been out this morning messing about although it’s raining cats and dogs and the car is outside at the mo so it’s not been much fun!

So I’ve determined the engine earth is good. Also the battery is definitely good which rules out supply and ground issues.

If everything is connected nothing happens except the ignition vacuum relay clicks once (relay in the drivers rear buttress). If I provide 12v direct to the (red/white wire) exciter input on the starter then the solenoid energises but nothing else happens. At that point I’d expect the starter to crank but literally nothing happens. Very odd.

I've even tried jump starting off another car to eliminate spurious battery probs.

My old starter worked fine until the solenoid contacts were too corroded to work any more. I’m at a loss!

I will ring SJ on Monday and get their opinion!

Anything I’ve missed?

[Clive59]

Do you have a voltmeter? If the starter solenoid clicks, can you measure what voltage you have on the starter motor side of the solenoid contacts. Could be a faulty solenoid not pushing the contactor bar fully home to make proper contact? I would be pretty confident the solenoid was faulty if you can hear it clicking. You might be able to do a DIY repair if it can be pulled apart.

If battery was low, the solenoid would chatter, as it provides current to crank, then voltage drops, solenoid drops out, voltage rises, and so on...

[Llewelyn82]

15 hours ago, Clive59 said:

Do you have a voltmeter? If the starter solenoid clicks, can you measure what voltage you have on the starter motor side of the solenoid contacts. Could be a faulty solenoid not pushing the contactor bar fully home to make proper contact? I would be pretty confident the solenoid was faulty if you can hear it clicking. You might be able to do a DIY repair if it can be pulled apart.

If battery was low, the solenoid would chatter, as it provides current to crank, then voltage drops, solenoid drops out, voltage rises, and so on...

Hi Clive, I can't get a meter on them unfortunately - It's all internal. The only thing I can measure on is the ground, the main "hot" post and the exciter input terminal (red/white wire connection). I get a healthy voltage on the exciter wire when the ignition switch is turned. So I've got good ground and power in the right places direct at the starter and it still won't work, not sure what else it can be other than the starter now! 

Battery had a full overnight charge and I tried again this morning to no avail so it's absolutely not the battery.

[Llewelyn82]

Well after speaking with SJ they are kindly sending me another starter motor.... Hopefully a working one this time !

[Llewelyn82]

Got to the bottom of this and it wasn’t the starter motor!!

Happy to snaffle a bit of humble pie

I didn’t get any life out of the starter by jumping directly from the battery which was why I was pretty much convinced the starter motor was at fault. My jump leads are shite or I was being an idiot and not clamping it on well enough. 

Turns out at some point I knocked the connectors off the throttle jack solenoid which caused a voltage drop on the exciter wire. I haven’t looked at the wiring diagram so I’m not sure why but at least the problem is solved. And it’s another thing to check next time my car won’t start!

[Escape]

Good to hear you got it sorted and it was an easy fix after all (i.e. without having to take the starter motor off again). I've had a quick look through the wiring diagrams, but can't find an obvious connection between the starter circuit and the solenoids.

Filip

[Llewelyn82]

9 hours ago, Escape said:

Good to hear you got it sorted and it was an easy fix after all (i.e. without having to take the starter motor off again). I've had a quick look through the wiring diagrams, but can't find an obvious connection between the starter circuit and the solenoids.

Filip

Me too - Very odd eh! But on my car, when it is disconnected the starter relay will not energise....