A healthy 6V Starter motor shouldn't have any problems spinning over a stock 45' engine. When is the last time you have the Starter gone through? When I rebuild the 6V Starter motors for our customer's, I have my rewinder wind the Armature a little "tighter" for more torque. Slow turning Starter motors are usually tired inside and need to be rebuilt the correct way. Not putting brushes, bearing and bushings in the unit and call it "good". Ten outta' ten 6V Starter motors that come in my shop for rebuild (even the nicely painted ones that just came out of another shop) have bad Armatures in them. That's where the torque and power is made. If nothing is done to change out a tired or bad arm, the unit will never perform as it should!  Even in the cold weather the unit should be able to start the engine, unless it's sub zero weather. That's another story. Using a 8V Battery or a 12V Battery is a bandaid. Get the Starter repaired by a replicable rebuilder. Also, make sure your cables are in good condition and not old either. Draw test the Battery to make sure that is in tip top shape to do it's job as well.

Steve@B&B

are your battery cables as big around as your finger or have they been replaced with the much lighter / newer auto cables ?  Those dont work well with 6v.

You've probably checked this already, but what about the battery terminals on the cable? Are either of them the universal style with the two little bolts that clamp a tab down on the stripped cable end? I've seen a boat-load of trouble and slow-starting being caused by them: Even when they look good and solid, the stripped cable oxidizes and has a very poor connection there.

Apart from that, I'm usually torn between the idea of converting to 12V. Yes, a properly tuned-up 6V system should have no problem, and it's definitely best to find all the problems before you change to 12V and just mask them. But even at the best of times when it' cranking at a good speed and torque, a 6V system can't crank for long before it starts to lose its gusto, especially since good 6V batteries with decent cranking amps are harder and harder to come by. If your engine's a little tired and sometimes requires more than a second or so of cranking, or if you've accidentally flooded it or something and need to crank for a little longer, a 6V starter system can be a little irksome. My justification for having recently converted my Super W6 is because 6V batteries with decent cranking amps and duty cycles are hard to come by and (when you find them) very expensive, and it sill makes it a pain for boosting other equipment (something I find I'm doing far too often).

One thing to keep in mind if you do the conversion: Most folks will tell you that you don't need to do anything with the starter: a 6V starter will work fine on 12V. While that's (kind of) true, a 6V starter run with 12V will really kick out with a lot of gusto, and this is the cause for a lot of sheared flywheel ring gear teeth on converted tractors. Which isn't the end of the world - it just means a ring gear replacement might be in your future a few years down the road. The old ring-gears don't seem to be hardened nearly as much as the newer aftermarket ones. I've replaced a few, and each time I've taken the old and new rings into work where we have a Rockwell hardness tester. The old ones are always down around 20-30 (Rockwell C) while the new ones are around 40+. One of the few instances where newer, aftermarket parts seem to be better than the OEM.

Ky.Allis wrote: If it were mine, I would plan on converting it to 12 volt at some point. I know many defend the 6 volt systems, but in my opinion they're junk. Good back in the day (over crank start), but there was a reason tractors, cars, trucks, etc. went to 12 volt.

Cars and trucks went to 12 volt because of the all the electrical equipment being added to them at the time:  air conditioning, power windows, cruise control, etc.  Tractors at that time did not have to worry about these options, so 6 volt was sufficient.

The electronic ignition is nice to have, but fix the problem you have with the Starter motor first. Take that $130. bucks that you would spend on an E.I. and put it towards the Starter repair. You can always add an E.I. later down the road. The only problem with the 6V system is there isn't a lot of good repair shops out there anymore that do a complete comprehensive job on the old 6V Generators and Starter motors. Older dudes like myself that grew up with 6V and know how to work with it, either retired or passed.  The other problem (and it really isn't a problem) some owners need more accessories such as additional lighting, or attach sprayers and whatever to their Tractors that need more current. When starting to add these types of accessories that need more power, (load) it takes the 6V system out of its realm to keep up with the loads put on that system.  Then, it would be a wise decision to change the complete system over to 12V. BTW, you can still use a Generator to power that 12V system. You don't need to move to an Alternator. The cost factor obviously is more than switching over to an Alternator, but it's completely up to the individual. Some fellers don't like the look of an Alternator on their Tractor that originally came with a Gennie. Again, it's their Tractor and their decision. The system just needs to be designed correctly for the loads that will be put on it. I've changed over many a 6V Gennie to 12V and designed systems that do not have any issues keeping everything on board the Tractor happy.

I've seen a lot of shoddy work over the 53 years I've been doing this stuff. If you have a replicable rebuilder near you that changes out the Armatures as well, then you're in the right shop! 70+ year old arms don't cut it. As I said, I build 12V conversion systems as well, and do a lot of converting Gennies, and Starters to 12V, but I'm not one to poo poo a 6V system. As I said, I grew up with 6V and was taught the correct way to rebuild units when I was a young lad. As long as the components that make up the 6V system are in tip top shape and everything is working together as it should, the old system is still reliable for what it needs to do.  You just have to keep an eyeball on it more and keep things in check so everything on board works perfectly...... HTH

Steve@B&B

The biggest difference between a 6v starting system and a 12v starting system is I2R... prounounced I-square-R.

Resistance limits current... while Voltage overcomes resistance.

The reason why automotive, agricultural, and industrial manufacturers went from 6v to 12v is BECAUSE THEY COULD.

Prior to WW2, manufacture of a 12v battery was considerably more expensive than manufacturing a SIX.  The internal difference is simple:  The leaded plates are THINNER, and TWICE AS MANY.  By doing this, the battery's ability to develop high current in COLD weather was over four times' greater... because battery CURRENT is a function of electrolyte contact PLATE SURFACE.

Prior to WW2, the manufacturing technology needed to make thinner plates was simply not an economic priority.  WW2 changed that, and the machinery appeared, making manufacture of large numbers of much thinner, but just-as-durable plates very inexpensive.  They didn't go to 12v... they went to 24, and it wasn't for farm tractors or pickup trucks, it was for AIRCRAFT.  Fighter aircraft, in particular, needed to be lightweight, but have the ability to start an Allison 1710 V12, and run electrohydraulics, navigation, radio systems, etc., while withstanding high G circumstances.

HEAVY plates in a 6V battery do NOT tolerate high-G combat maneuvers.  6V batteries located in the middle of an aircraft cannot crank a 1711 cubic inch V12 when there's 18 feet of battery cable in the circuit... the I2R losses are simply too high to carry that cranking current.  Even at 12v, it wasn't enough.  Go to 24v, and now you're at 4x the voltage, but you're only trying to carry a quarter of the current, and that means you can use SMALLER, LIGHTER battery conductors and still get the job done.

In an aircraft circumstance, one only needs to be able to start ONE engine.  Once one is started, the first engine HELPS start the rest.

Back to cars, trucks, and agricultural-

Most starter motors are SERIES WOUND.  That means the field and the armature are in series.  The operational character of a series wound motor, because of the armature and commutator, is an AC device... meaning, the magnetic field relationship between the field and armature, since the armature's polarity is reversing, it is technically an AC circumstance, which is to say, there is a point where the armature's magnetic field cannot reverse any faster.  When the armature reaches this point, it's internal reactance (inability to operate beyond a certain speed) means it is also limiting the FIELD current, and thus, the motor can spin no faster... it is self-regulating in upper speed.   A series wound motor is NOT quite the same, in that it reaches it's limits in a significantly higher range.

When Delco developed their industrial starter line, they did something very interesting- they calculated the windings carefully, and manufactured them to operate well on SEVERAL voltages.  They did this so that it was not particularly necessary to manufacture 3 different starter motors to be suitable for 3 different battery voltages.  My big generator, for example, is a Hercules JXLD 338ci inline six, it's starter motor was included in the generator package for a 24v military contract system.  This starter will start the engine basically the same way, with four big 6v batteries in parallel, that it will with the batteries in series-parallel (for 12v) or in series (for 24v.

The difference is, I can put ONE 12v Group 24 battery on it, with a pair of 4ft cables, or I can put TWO lawn-and-garden batteries at 24v on 15ft cables, and it'll still start just fine.

ANY starter on an old engine will benefit from a genuine freshening.  As Steve noted above, the armature needs attention- megging the windings, or running it on a growler, getting the backcut on the commutator... those are things many shops just don't do.  My guy down at Gillespie has a growler AND a megger.  I have a growler and a megger.  I don't know any other people in my area that have a growler and a megger...

The battery cables, connections, and starter SWITCH SURFACE on a 6v system are FOUR TIMES AS CRITICAL as on a 12v system.  Most guys overlook that starter switch.

When you electrically crank an engine, you're asking that (cold) battery to put a SERIOUS amount of current through wires to that starter motor.  Your electric ignition system's voltage during cranking is LOWER as a result... and as a result, your ignition output is considerably lower.

An electronic ignition will fire much more reliably than a contact point/condenser system, but low voltage is low voltage. 

IF you crank the engine, and it fires the moment you RELEASE the key or button, it's because your starter's power draw, and your wires' resistance is causing the ignition system's voltage to be pulled TOO LOW to develop sufficient spark energy.  If you install a jumper wire from the ignition coil's power terminal directly to the battery post AND you provide an additional ground path from the ignition (usually distributor base) to the grounded battery post, and the engine starts better... then fix that wiring... oftentimes it's power wiring AND the ignition switch.

Converting your tractor from 6v to 12v doesn't 'mask' any problems if you address ALL the components.  There's nothing wrong with running 6v, or 12v on your starter, they're frequently no different aside from the tag (and oftentimes, not even that)... just go through everything else while you're at it, and you'll find it very happy afterwards.

Way back in my youth I owned a 1955 Ford 4-door Customline; it had a 272 V8 and 6 Volt Positive ground. It was well-maintained and in good condition, other than lights and starter the only electrical accessory was the AM radio which I never used, this car had vacuum wipers (they truly do suck).

1955 was the last year for 6 Volts on Ford cars, and I have a VERY clear understanding of why they switched to 12 Volts in 1956

Yes, 6 Volts was indeed "sufficient". It always started. Even in cold weather. Just. Barely. Started. But you always wondered if it would.

I always parked the tractor on a hill...just...in...case...:)

dr p wrote: Professor Dave, Is that all going to be on the exam. LOL I had to get my nephew going to cornell to explain half of that to me.

I was an Avionics tech in the Marines, and I have an Electronics degree in Bio-Medical Engineering.

When Dave talks, I listen

.

6v is fine until it reveals unreliability.

Then I convert to 12v. No time for messing around and trying to maintain 'originality'. Be practical.

Go through and polish all connections and lube with dielectric grease to protect from corrosion and oxidation.

.

I may need another coffee to clear my head.  I am not following how you have 12 volts at the starter unless you wired the two six-volt batteries in series.  If both batteries are wired to the starter they would be parallel and still only provide six volts at the starter (with greater CCA available from the combined two batteries).  If wired in series it doesn't seem it would charge both batteries or work properly as a straight six-volt system.  Do you have a 6/12 series parallel switch?

Mine was about $280 but they replaced some additional things like the throw-out gear and upgraded a sleave to a ball bearing.  Delco-Remy parts appear to be easy to get.

AC WD45 wrote: My 57 WD45 has a D17 kit. Still on the factory 6v system. The solution was to add a second 6v battery in a WC box on the frame rail where it would go on the WC. The holes are already there IIRC. We wired that battery to the starter. This gives the starter 12v when cranking and that tractor will fire off on the coldest day of the year. Cranks over nice and quick. 3 or 4 turns sometimes less and it fires.

If you truly have 12 volts to the starter that means you have the batteries wired in series (6 + 6 = 12), this also means you are trying to charge this 12 volt combined battery with a 6 Volt generator.

Unless, as was mentioned above, you have a 6/12 parallel switch, but if it is wired correctly it will then switch back to the equivalent of one big 6 Volt battery and will charge it as such.

You can put 16 6V Batteries in that Tractor, but if the Starter is completely shot it's gonna draaaaaag or do nothing!  As far as the cost of rebuilt Starters, it greatly depends on the Starter type and design. For a 6V Starter rebuild say for a B,C,CA Tractor, I charge $285. And that's with all new components, rewound Armature in it for a little more torque, and a new switch to boot.  For a few more bucks, I can set it up with a Starter solenoid getting rid of that PIA mechanical switch.  Different Starters have different components inside em'. so rebuilding prices vary. Also, it depends on what condition the Starter motor is in as well. Probably the hardest part of the whole thing now a days is finding a shop that still does a great job and does it right. Us older dudes are retiring or passing. I'm still hanging in there yet, but one day I"ll be hanging it up as well.

'

Talking about 55' Fords with 6V systems, Jo Jo's T-bird was 6V with vacuum wipers. Wow, all that had ta' go. I wound up wiring that vehicle Headlight to Tailight and installing an electric wiper motor in the middle. Upgrade the blower motor to a 56' T-Bird motor (12V)  The main reason I did that is so I don't have to chase after her if she breaks down.  It also has disc brakes up front so it stops for the Deer around here, and an O.D. tranny in it out of a 86' T-Bird to cruise down the highways.  Oh yeah, and a Pertronix E.I. too!  That thing runs sweet!

Sometimes you're better off purchasing a new Starter if its available than trying to rebuild the original. All depends, on application, availability the individual that owns the vehicle, and the shop doing the work. Every year it gets tougher and tougher to get quality parts for these rebuilds. Its a good thing I bought inventory from old electrical shops years ago that closed up with this old stuff, so I have a little bit of inventory of parts myself. I don't have everything though that's fir' sure!

Steve@B&B

That's exactly why, and more, Les...   the 272 V8's cylinders were 3.6x3.3, and occuring twice as often, vs. the WD45's 4x4.5.  The V8's larger bore/shorter stroke, and divided amongst twice as many cylinders meant that the force required to cross TDC on a compression stroke was significantly less, EVEN WITH more moving parts.

My '29 Ford A still runs the 6v foot pedal... and it doesn't matter WHAT time of year... starter, cables, battery perfect, fuel on, mixture set, choke set, spark advance retarded, ignition switch on, push the pedal and it's Errr.... rrREER.... rrREEER.... PlharoOOOMmmm... cough cough cough... fup fup fup whatta fup whatta whatta whatta.....

The three turns is a logical thing-  when an engine is cold, cylinders have no charge... you have to cross three compression strokes to get to one cylinder that's gone through a full intake cycle, and that's where (under normal circumstances) your first ignitable charge will be.  My neighbor is amazed that my '38B hand starts so predictably on that third pull.  Now... on engines that have primer cups, they'll fire on the first compression stroke.  My Fairbanks Morse ZC-118 and ZC208... push the intake valve open, give 'em a quick touch to the primer button, and pull the flywheel up to TDC, and just a little past, as soon as the magneto impulser clacks, it's running... so keep your fingers out'a the spokes!