bedford k 6 volt to 12volt conversion

My old Bedford K has not been run for a few years , It is being very hard to start . With my 6 volt battery it turns over , but real slow , probably too slow to get it firing . I do have good spark and fuel ( and Aerostart) I intend putting a 12 volt battery over the starter to get it spinning a bit better . So I am asking about any thoughts on doing this .
Now this also got me thinking ... would it ultimately be better to change the truck over to a 12 volt positive earth system using a more modern alternator etc . Does anyone have experience in this type of conversion .
In the short term I would really like to just get the truck running , and easy enough to start to give it a spin around the paddock every few weeks . The truck probably wont ever make it onto the bitumen though .
Thanks for reading this
Richard

Depending how functional you want it, you could just disconnect the wiring from the coil and starter and just run it off a 12 volt battery with a light cliplead to the coil. The 6 volt starter won't be too bothered and will spin over quite fast, but I think you will have to change the coil to a 12 volt one.
It's likely your 6 volt battery is too old. My Studebaker winds over just fine on 6 volts. You could try stripping and cleaning all the starter connections, too.

Jarrod.

My O series got a bush conversion to 12 volt, I was lucky to find a working 12v genni got a 12 v coil & fitted them, changed a few globes. I must have changed the voltage reg but dont remember doing it. and the capacitor in the dizzy gave up after about 20 hours of driving around the paddock.

The starter was very happy on 12 volt.

Sarge, thanks for this , I am pleased the started seemed to handle 12 volts . It seems that there is not too much to change over .

Jarrod, I think you are right about my battery . The coil will have to be changed yes , but it is alot easier to find 12 volt coils than 6 . Also I am thinking going forwards having 12 volt battery is alot easier to find on the property than 6 . So i might make the KSeries a 12 volter .
I must clean my connections too .
Cheers

Hi Richard Salter I have a 12 volt gen and a 12 voltage reg. from my TJ Bedford, because I have put a alternator in it. I see you are in SA I am in Vic. My brother lives in Adelaide, I am catching up with him in a couple of weeks. If your are interested I can give him the 12 volt gen to take over. With the 12 volt reg, I have not finished with it, the alto electrician wants to see were the wires are coming from. But are happy to post that later. But it might be ready to go all together by then. I do not know if it all works or not, but it is free to a good home. With the 6 volt starter I was told it is fine to run 12 volts. but not to work it to hard and to give it a rest if having trouble starting. My phone no is 0467531875. This is a few photos of my fit up. Cheers Fill

100_2765 by fill quinn , on Flickr

100_2763 by fill quinn , on Flickr

Most modern (up to EFI) vehicles actually ran a 6volt coil with a ballast resister so wired that the coil received 12volts when cranking and 6volts when running. This did 2 things. 1, it overcame voltage drop whilst the starter was spinning and 2, it improved the spark for better starting.

I'd fit an alternator and run neg earth This would mean all light globes would need replacing and you could run another ballast resister to step the voltage down for the dash.

Ultra reliable and easy to do.

The old Lucas 6v systems can be run quite successfully on 12v,just by adjusting the regulator,and changing the bulbs.....the old third brush generators just need the battery changed.......My old Coles crane was setup with 2x12v batteries as 24v when I got it.......After about 12 months the generator burnt out,and I discovered it was actually made as 12v,and Bobby Addison had connected it up to 24 to make the motor start easier.....it was a P6 Perk,and he had fiddled with the pump,stuffing up the timing.

Weren't the old side valve Morris engines much the same set up?
Bloke I knew replaced the battery with a 12 volt without too much harm, swapped the original 6v genny with a 12v Holden. He used to leave the bakerlite cover off the voltage regulator and jam a couple of wooden matches against the solenoids to close the points and charge the system.
Which makes me think that the regulator itself must have been unaffected with either 6 or 12 volt, maybe only the solenoids themselves were voltage conscious, probably that was the idea of the matches, burnt the solenoids out??
Dave

Your old starter is probably "poling out"......and the commutator is probably also suspect......in other words ,its plumb wore out.