6 Volt Starting

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356Monkey
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6 Volt Starting

Post by 356Monkey »

Ok so it must be at least 3 months since someone banged on about deathly slow 6 volt starter motor issues so I'll reboot the conversation. I just changed the starter bush in my car as a bit of a last resort. I fully restored my car, it has a new wiring loom, hot wire from battery to start, voltage regulator, new battery, new earth straps on perfect clean metal so I was running out of options to fix the dreaded slow starter. I've got to say that when i removed the old one and compared it's fit on the end of the starter motor with the new bush there wasn't a huge difference but you know what? It worked, the starter turned really well now!!

I'm glad as I was thinking about biting the bullet and going 12v or forking out for a high torque starter. I have no issue with either of those options but I guess the 6 volt system will work just fine as Dr Porsche intended as long as all the elements are working well.
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Julian Hunt
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Re: 6 Volt Starting

Post by Julian Hunt »

Whenever anyone asked me about a starter motor issue the bush was the first thing I would suggest they change every time.
Its amazing how a £5 bush can cause so much trouble, and it's amazing how many people don't change them!
Mike Smith
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Re: 6 Volt Starting

Post by Mike Smith »

Whenever anyone asked me about a starter motor issue the bush was the first thing I would suggest they change every time.
Its amazing how a £5 bush can cause so much trouble, and it's amazing how many people don't change them!
+1 - Julian

The other thing that nobody ever looks at are the contacts inside the Solenoid
They take the the full amp blast and are often heavily burnt

Of, course its a bit more work to get to them
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roy mawbey
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Re: 6 Volt Starting

Post by roy mawbey »

Ah Mike how true your words are concerning the Solinoid points situated under the cover on the starter itself. I did all the checking of earths, connections, changing the bush in the bell housing for the starter drive shaft and a check of the motor brushes. What did all that do, well for me it improved it somewhat but ... a hot engine and the start up crank was still terribly slow. I did wonder what was under the factory soldered ? on top cover of the solinoid but never was brave enough to find out!
Broadway electrics in Essex were and found all the contacts inside totally covered in dirt and burning from the start ups from 1959! They checked everything else which were okay so put new carbon brushes for the commutator cleaned the solinoid contacts till perfect and drilled the solinoid cover for small nuts and bolts.

Mike is right its not an easy item to replace its heavy and without a ramp hard on your back. Move the loom out of the way position the top bolt and stick it there with bluetac and with the end of the bolt able to go into the reception.

What a result that was now as fast as a 12 volt hot or cold.

Roy
RHD 356A coupe super 75 106954
Peter Roberts
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Re: 6 Volt Starting

Post by Peter Roberts »

i Suffered the same problem for years and put out a post on how i resolved it. I to was going to go 12v during a major restoration but the forum advised if Porsche could get it to work then why change it as problems would likely to be just maintenance not 6v. Apart from overhauling or replacing everything electrical i also put on two engine earth straps with one directly onto the starter motor and i double bolted the battery earth cable using a thick copper strip. The result is a starter that flies over. I also incorporated a rally style battery master switch. Not only does this guarantee no battery drain it is also a very good anti theft device. I left my car unused for 3 months without charging . On start up the engine spun over at a rate and once the floats were full burst into life. My advice is stick with 6v and get everything reconditioned and all contacts scrupulously clean.
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Ashley James
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Re: 6 Volt Starting

Post by Ashley James »

I’ve a 6 Volt Hi-Torque starter motor from Powerlite on the car and a re manufactured Bosch on the spare engine in the workshop. Both work as well. But I believe the hi-torque pulls less current and it’s far easier to fit and doesn’t need the bush that otherwise has to be replaced.
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