Starter motor

[kachel 5]

In the last 2.000 km (in 2 years) I have replaced the starter motor 3 times..... The issue is the the same every time. When I turn the starter motor I hear a click but no turning over of the engine. With a few pulls of the car in the 3th gear it will turn over again. Is it bad luck that I bought 3 times a bad second hand starter motor or could it be something else? Battery is new. 

[jackherer 543]

It's a very common issue.

 

It is usually a fault in the wiring to the solenoid or the brown multiplug it runs through all the way back to the ignition barrel. Or the barrel itself. Or the wiring to the barrel. Or the barrel itself.

 

It could also be the battery clamps or cables including grounds.

 

Have you tried applying +12v to the solenoid terminal directly when it has failed at any time? If that works you can rule out the starter, it is also very unlikely you have had multiple faulty units.

 

On the odd occasion (probably less than 1 in 50) I have seen this problem and it actually has been a faulty starter motor it consistently only failed when warm.

[kachel 5]

Thanks! I'll start with checking if the starter motor will turn with 12v directly on the selenoid. If there is still a click but no cranking I know it is the starter motor again. 

[toolie72 67 1 Cars]

Worth checking the starter is earthing correctly. Jump lead back to negative terminal from starter body.

Earth point is on gearbox and can get manky

[Telf 224 2 Cars]

Agree with what's said above. I've had this fault on and off for ages. Having built and fitted all new wiring in the engine I was surprised when I had another start fault. I was convinced it must be the starter solenoid and did a quick check of when I last replaced the starter ... 3 years ago but only 800 miles due to the refurb of the car. Probably not that then. 

 

Investigating further I replaced a very worn ignition barrel loom that as seen better days having clearly been messed with over the years as various immobilizers have been installed. With the new loom fitted I tested the start and nothing happened even though it had been working 5 minutes earlier. Much cable wiggling and fault found - the ignition able on the brown plug under the steering column. 

[kachel 5]

Ah, you mean check the earth wire from the ignition barrel to the earth point on the gearbox? 

I assume the starter motor gets earth from being mounted to the gearbox? 

Or am I way out now? 

[jackherer 543]

The starter is earthed to the gearbox but the gearbox itself is connected directly to the negative battery clamp.

 

Check that wire at both ends, the battery clamp and the ring connector where it bolts to the gearbox, there should be a serrated washer so it gets a good connection.

[kachel 5]

OK, thanks for clearing that out. 

The thing that bothers me (without testing based on the very helpful information above, I will start testing off course) is that I hear the famous click of the starter motor when turning the key. This click happens also with faulty earthing? 

[jackherer 543]

Yes, when the voltage at the starter solenoid is too low for whatever reason it will either do nothing or just click.

 

The best test is to apply +12v directly to the solenoid as I described above, just make 100% sure it is not in gear and keep your hands away from the alternator belt.

[kachel 5]

Great info, thanks for helping me understand this matter. 

Today I tried to start the car and it directly turned around. The car hasn't moved since the last time I tried starting it with only a click as a result. 

 

[Telf 224 2 Cars]

It started from a direct feed from the battery to solenoid? You have a wiring fault then. Good work

[kachel 5]

So today I got some time, I also needed to replace the thermo sensor in the radiator. Next to that I have checked the earth wiring from the battery to the gearbox. The cable seems to be fine, no rust or lose ends. But the connection on the negative pole on the battery was quit wigly. (is that a correct word?) So I have replaced the negative pole clamp and now it is secure again. I might be wrong but I think when I turn the ignition key now the response of the starter motor is faster. In my assumption there was always a little delay in turning the ignition key and the reaction of the starter motor. So... I have real prove that it is solved, but the first signs are good. Time will tell. 

 

[jackherer 543]

The faster response is definitely a good sign!

 

It's often more than one thing though, each bit of high resistance adds up so don't be surprised if the problem comes back at some point.

[kachel 5]

Yes indeed. But for now I am satisfied. 

Thanks!