Is it my starter motor???

I have a p reg disco 1 and i have recently been having problems with starting, Some times she starts sweet as a nut but then sometimes my starter sticks on even with the key removed and others it fails to start altogether like a flat battery. I have tried fitting a new ignition barrel to try to counter the sticking problem as mine had started to collapse anyway but still having difficulty. I havent seen any of the tell tale glowing down the side but have fitted an isolation switch so that when it does stick is isnt on for too long. Not sure if i need a new battery also or what. Really dont want to pay out on a new starter if it may be something else such as a connection somewhere. Does anyone have any tips on what to check before buying a new starter?

Could be the starter solenoid than the motor it's self, there kits to repair it I believe, but if the engine doesn't crank you may have an iffy 'spider' immobiliser, assuming u don't have a Tdi auto.

There are Threads on bypassing the spider.

How old is the battery? If it is over 3 years old it may be worth getting it load tested to check its cold cranking capacity. Also check the earth connection from the engine to the chassis.

I am sure there is a relay which goes to the starter motor on the V8. I think it is in the driver's side foot well.

If you need to change the starter motor and the engine is a V8 then I found it was easier the remove the exhaust manifold and remove the starter upwards rather than how the workshop manual tells you. You will need a allen key socket (unfortunately I cannot remember the size) and a number of wobble extensions to remove and refit the starter. Ideally have someone with you to assist.

thanks for the suggestions guys, car will crank but seems lazy sometimes, even after changing the ignition, could a lazy battery cause the starter motor to stick on, or is it not receiving the stop signal so to speak after the engine starts from where ever the signal may come from (sorry don't know much about these things but need to learn as cash is tight). hence the need for the isolator switch as even removing the key from the igniton the starter motor is still whirring .

hope this helps

nina

Well, here's the first test.

If you can get access to the starter find the small cable that goes to it. Should be just a push on connector instead of bolt on like the rest.

If you can get it to stick on (ie when it won't stop cranking) pull that little cable off and see what happens.

I suspect nothing will happen (it will carry on cranking) in which case your starter needs attention.

Could be a rebuild (diy free), recon (small cost), replacement (second hand about 50 quid max I think)

Hope that helps.

The starter motor relay in behind the side panel in the drivers side foot well. The relay should be the second one from the back. The colours of the wires to the relay base should be:-
85 - white with red stripe
86 - black with orange stripe
30 - brown with white stripe
87 - brown with red stripe
Pin 87 is the switched supply to the starter which connects to the starter solenoid but it goes via the spider first (if fitted).

thanks for all the replies so far guys going to check the relay tomorrow and some of the other suggestions and if still failing will take the starter off and have a closer look on the week end, thinking of also checking the vehicle engine to chassis earth cables to.

My instructions should, IMO, be carried out first as this simply tells you whether it is starter or car.

There is zero point faffing about with the problem until you have made this simple test!

I agree as I suspect that the starter solenoid is the most likely cause of the problem.