Voltage to Starter Motor

[crazymatelot]

Does anyone know what controls the voltage to the starter motor? My cerb has been playing up lately. Instead of engaging the starter justs clicks, some people have said that the starter motor solonoid arm is too long by a couple of thou but I don't believe this. When the solendoid clicks the voltage to the starter is down to 10 Volts, when it fires up I have full voltage of 12 + volts to the starter. Something is intermittently reducing the voltage, I suspect a relay or something in the boot, but could it also be either the immobiliser or ECU?

[Jackal83]

i'm not sure on the TVR starter but most other starts have an earth going from the solinoid to the rear of the starter... if this cable is bad it could give a clicky noise because it wont be able to get the power to it...

Also is the starter earth ok???? run a jump lead/cable from the starter to the earth of the battery and see if you are having a bad earth problem....

Jack

[Jitzz]

Hi Guys,

I had a similar problem with my starter some time back, (see my posts) as it gave me the same 'Clicky' sound - not good when your at the petrol station !!

I removed mine and had a new solenoid put in by an auto electrician, who also checked the whole starter over. I also cleaned up my earth cables up and ran a new one form the battery to the starter body as suggested.

Before all this though, just to check whether the starter was knackered or not, I ran a positive feed from the battery onto the kick lead - and she spun up which suggested to me it was OK, but I had an 'Overhaul just the same !!

I also fitted a 'hidden' switch which runs a direct postiive feed to the starter, just in case the 'clicky' returns


Hope this helps

Jitzz

[gruffalo]

Sounds like starter refurb time, mines in at STR8SIX at the moment having this fixed as well as a few other bits done before winter. This is a well known problem, original unit was only just up to the job but a small amount of wear stops it working.

The Voltage droping down to 10 volts is because the starter is not turning there is no back EMF but the current is being applied so in effect yo have stuck a great big piece of metal across your battery terminals there fore reducing the potential difference which is what Volts is a measurement of.

[crazymatelot]

Thanks for all the comments and advice. The starter motor is brand new and was fitted by a local garage, who measured the voltage drop. I have managed to start the car and get it home. I shall now investigate further.

[AlexH22]

Sticking soleniod? Sometimes a tap with somthing like an extension bar can be enough to provoke it and unstick it, granted its a short term cowboy bodge.

If its brand new, i`d be checking the wiring and make sure the local garage put all the wires back and earth's are clean etc.

[gruffalo]

You didn't get the new starter from RaceTech did you, I had a chat with some one in the know about those and he wasn't complimentry, lucky if they work.

Having said that just sent mine back to be rebuilt for the third time this month, hope they get it right this time.

[headcase]

I remember a while back this was a common problem, i think it was generally cause by the length of the cable that goes to the starter (goes around the car several times and via several connectors) eventually ending up with about 8v at the starter. The most common bodge was to mod the starter circuit so that a freash relay powers the solenoid from the battery using the 'Original' solenoid wire to power the new relay. Also possible an immobiliser problem (dry joints) as it goes via there on its travels. Apparently if you hold your finger on the starter button for ages and it eventually starts to turn over then its the immobiliser.
Suggest you do a search as all of that was from memory so could be slightly wrong