Starter Motor Fault - When Hot.

[Willy Eckerslyke]

Hi, got a 1.6 diesel on a 57 plate.

 

The engine turns over and starts as usual when the engine is cold but after a journey and once the engine is up to running temperature, if you stop the engine and then try to restart it 50% of the time it will not turn over. If you try to start it 3,4, or 5 times eventually it will turn over as normal and start. Also if you let the engine cool down it starts as normal.

 

Battery was tested and was ok. When it doesn't start there is an audible, single click or knock, not very loud but it is there.

 

When it happens it is just like trying to turn an engine over where the battery has gone almost totally flat and the starter will not spin. I took it to the garage and at first he said it was the battery but on testing this was not the case. For some reason the mechanic at the garage said he thinks its the starter but is not prepared to change it until the car won't start at all and they can diagnose it ?

 

Only problem is that we now have a car we can not rely on. Can any one throw any light on the matter as using the car until it fails altogether is not really an option.

 

Thanks for reading.

 

Bigted

[paul.h]

I guess all the wiring, connections (battery and starter) and earths have been checked. If it is just clicking and the wiring and battery are ok then it could be the solenoid on the starter is not making a good connection to allow the full power to turn the starter - if the starter is accessible, a jump lead could be used to provide a supply direct to the motor bypassing the solenoid to show this. Or maybe the starter motor electrical brushes are worn.

 

Who is going to pay for the work, you or the garage which could explain the reluctance to fix the car.

 

How many miles has the car done ?

[Willy Eckerslyke]

Hi, I am paying for the work and the car has done 75000.

 

Thanks for your comments. When I initially took the car in to the garage I rolled up outside told them it was not turning over and starting when hot. They grabbed a power pack, we went out side, I tried to start it nothing , they stuck the jump leads on and bingo.

 

They immediately said its the battery. I took the car to a battery agent he tested it and said nowt wrong with battery. Back to garage and left the car there. Picked it up later in day and they said they had started it 30 times in a row no problems.

 

This is where the problem lies in that the fault only starts once the engine is up to running temperature and hot. From cold, turns over from the off and starts immediately.

 

I just wondered if there was any obvious reason why a failing starter/solenoid would show up when hot and behave perfectly from cold. You would think it would be the other way round.

[Johndouglas]

 why a failing starter/solenoid would show up when hot and behave perfectly from cold.

 

One of the rules of physics is that resistivity increases with increasing temperature.   If you have satisfied yourself that all the connections are solid - including the earth straps from battery to ground, the next item to suspect is the solenoid.   You can check it by carefully connecting directly from the starter to the battery with a jump lead.  

[Willy Eckerslyke]

Tha

 

 

 why a failing starter/solenoid would show up when hot and behave perfectly from cold.

 

One of the rules of physics is that resistivity increases with increasing temperature.   If you have satisfied yourself that all the connections are solid - including the earth straps from battery to ground, the next item to suspect is the solenoid.   You can check it by carefully connecting directly from the starter to the battery with a jump lead.  

 

Hi, thanks for that, yes of course you are right. I am thinking back now to hearing about chilled super-conducters etc. 

 

I will try the solenoid.

 

Thanks