Terminal Box question

Bud Camp

Member
OK, I'm really frustrated. Yesterday, after two weeks working on my 30 pickup installing new original wiring, a new oilpan gasket and timing gear, I tried to start my truck and nothing happened .The horn worked, however. I had it running after I replaced the timing gear and the wiring seemed ok. So I took the battery to a parts store and they said it was good, just needed charging. So I put it on trickle charge all night and tried it this morning. Nothing but the horn worked better. So, I'm thinking that maybe I've somehow got the wiring messed up. Heres my dilema. In the wiring diagram, The terminal box is rectangular terminal box is vertical and my box is horizontal so I don't know which wire goes on which terminal. As I look at the box from the front of the engine, which side does the red wire connect to, passenger or drivers side. Does it matter? I am also thinking that maybe something might be wrong with the starter but don't want to pull it out until I make sure the wiring is absolutely right. Any ideas.
 
Hi Bud, I recently did a search here on the Barn for a schematic,and I found one that
Mike V. Florida posted. It says '28, but it provided what I needed for my '31 S/W.
 
Hi,
Your diagram is only verticle if you do not realize it is a TOP view, which now makes it horizontal. Note the right headlight is ABOVE the left headlight in the diagram.
THAT SAID, the 1928 electric diagram from the Service Bulletin has the yellow from the starter going to the passenger side and the yellow black from the driver's side going to the generator.

I hope this helps.

(If things are reversed your amp meter would show a charge with the lights on and the engine off.)
 
Please expand on "nothing happened." Did the engine turn over and not fire? Did it just click? Grunt? Do you have lights? Is your battery hooked up positive ground? Is your car stock? We need more info and symptoms here to diagnose the trouble.
 
With a Stock model A the only wiring for cranking is battery to starter, and battery to ground --I suspect that if the horn works you have that, and also with Stock wiring if the horn works the wiring to and from the terminal box is connected, and if the ammeter reads discharge probably correct, if the lights don't work look at the interface of the switch and horn rod---is the "spyder" hooked to light switch---what parts are original ford parts, what are repro (always suspect the repro parts)
 
The motor did not turn over at all. Thanks to the repliues I checked and I have the terminal box wired properly so its probably the battery or the starter motor.
 
a battery terminal that is corroded can make the horn work, but not pass enough to run the starter motor, also a battery can get a internal connection problem that runs low amp items, but not the starter, how did it work before the wiring change?
 
Hi Kurt

It worked fine and cranked the motor well even after I changed the wiring. I'm taking the battery back to the shop to get checked again.
 
A relatively inexpensive yet useful item to have on hand is a battery hydrometer, available at any auto parts store. A battery with a weak cell, will still read 6 (or 12) volts between the two terminals, but as stated above, may not have enough cranking capacity to engage the starter. Thus, sometimes just measuring battery voltage may not tell you much about the battery.

Presuming the battery is not of the sealed type (that is, you still have access to each cell), then taking a specific gravity reading on each cell with the hydrometer will frequently point up the weak cell (similar to a compression check). Typically, a fully charged lead-acid battery will have a specific gravity around 1.280 (sometimes spoken “1280”) so that if you get a series of readings for the cells of around 1.265 to 1.280 but one cell reads 1.090 (for example) you can presume – if this cell doesn’t return to normal with charging – that this cell has failed and the battery ought to be replaced.

If, on the other hand, the electrolyte level covers the plates, all specific gravity readings are fairly consistent (+/-) and increase with charge (and come up to somewhere around 1.280) then the battery is probably good and the problem lies elsewhere (elsewhere being – usually – corroded terminals/connections or a failed component, depending on the problem).

If all the battery cell specific gravities are consistent but do not increase (significantly) with charging (or the charging rate in amperes doesn’t decrease with time) the battery has reached the end of its life and should be replaced.

If the battery is a fully-sealed unit, and you don’t have access to the cells, then the only reliable test I know of to ascertain battery condition is a load test that actually puts a resistive load on the battery long enough to determine if it’s still good.

When you are done measuring the specific gravity, rinse the hydrometer out with tap water so that the electrolyte (sulfuric acid, H2SO4) doesn’t get all over everything.

And if you need to top off the electrolyte level, use distilled water (please don’t take offense at this advice, inasmuch as you never know the experience level of whomever posts the original question or reads the subsequent replies). Small amounts of tap water will not cause the battery to instantaneously go belly-up, but the minerals in most tap water (and the chlorine – or whatever treatment agent your municipality uses - in many municipal water supplies) don’t help battery life.

Btw, if you don’t have a battery hydrometer but do have a multimeter, you can actually read the voltage from one terminal through each cell successively by momentarily dipping one multimeter probe tip into the electrolyte. Thus, starting with the grounded terminal of the battery, you should see about 2 volts between that terminal and the first cell, 4 volts between the ground terminal and the second cell, and so on (each lead-acid cell generating about 2.2 volts DC which – with internal resistance – results in about 2 volts per cell). Rinse off the electrode tip when done.

And, lastly (based on my experience on several occasions following my forgetting to turn off the lights after parking my coupe) you would be surprised how many times you can start your Model A with the hand crank and a supposedly “dead” battery. If you know how to do this (there is a good description and photo under “hand cranking” in the Victor W. Page’ “Model A Ford Construction, Operation [and] Repair for the Restorer”) this may help tell you whether you have a battery problem or starter (or ignition) problem without schlepping the battery back to the auto parts store. Besides, imho, every Model A driver ought to know how to start his/her Model A with a hand crank.

Ok, a long post and probably more than most want to know about lead-acid batteries. At least I didn’t include the battery equations (once a submariner, always a submariner…)
 
Skip,
No,No, No, NOT too much info! Folks need to know about battery functions in order to get the MYSTERY out of how they work! Like when most of the acid is driven into the plates, leaving mostly water in the cells, thus causing the specific gravity, (weight) to change. Charging then forces the acid back into the solution & specific gravity, (weight) increases. Bill W.
 
Starter may be stuck. If the hand crank won't turn the engine, the starter drive is stuck. Shake the car back and forth in second gear and when you hear it click the starter will be unstuck.
 
A relatively inexpensive yet useful item to have on hand is a battery hydrometer, available at any auto parts store. A battery with a weak cell, will still read 6 (or 12) volts between the two terminals, but as stated above, may not have enough cranking capacity to engage the starter. Thus, sometimes just measuring battery voltage may not tell you much about the battery.

Presuming the battery is not of the sealed type (that is, you still have access to each cell), then taking a specific gravity reading on each cell with the hydrometer will frequently point up the weak cell (similar to a compression check). Typically, a fully charged lead-acid battery will have a specific gravity around 1.280 (sometimes spoken “1280”) so that if you get a series of readings for the cells of around 1.265 to 1.280 but one cell reads 1.090 (for example) you can presume – if this cell doesn’t return to normal with charging – that this cell has failed and the battery ought to be replaced.

If, on the other hand, the electrolyte level covers the plates, all specific gravity readings are fairly consistent (+/-) and increase with charge (and come up to somewhere around 1.280) then the battery is probably good and the problem lies elsewhere (elsewhere being – usually – corroded terminals/connections or a failed component, depending on the problem).

If all the battery cell specific gravities are consistent but do not increase (significantly) with charging (or the charging rate in amperes doesn’t decrease with time) the battery has reached the end of its life and should be replaced.

If the battery is a fully-sealed unit, and you don’t have access to the cells, then the only reliable test I know of to ascertain battery condition is a load test that actually puts a resistive load on the battery long enough to determine if it’s still good.

When you are done measuring the specific gravity, rinse the hydrometer out with tap water so that the electrolyte (sulfuric acid, H2SO4) doesn’t get all over everything.

And if you need to top off the electrolyte level, use distilled water (please don’t take offense at this advice, inasmuch as you never know the experience level of whomever posts the original question or reads the subsequent replies). Small amounts of tap water will not cause the battery to instantaneously go belly-up, but the minerals in most tap water (and the chlorine – or whatever treatment agent your municipality uses - in many municipal water supplies) don’t help battery life.

Btw, if you don’t have a battery hydrometer but do have a multimeter, you can actually read the voltage from one terminal through each cell successively by momentarily dipping one multimeter probe tip into the electrolyte. Thus, starting with the grounded terminal of the battery, you should see about 2 volts between that terminal and the first cell, 4 volts between the ground terminal and the second cell, and so on (each lead-acid cell generating about 2.2 volts DC which – with internal resistance – results in about 2 volts per cell). Rinse off the electrode tip when done.

And, lastly (based on my experience on several occasions following my forgetting to turn off the lights after parking my coupe) you would be surprised how many times you can start your Model A with the hand crank and a supposedly “dead” battery. If you know how to do this (there is a good description and photo under “hand cranking” in the Victor W. Page’ “Model A Ford Construction, Operation [and] Repair for the Restorer”) this may help tell you whether you have a battery problem or starter (or ignition) problem without schlepping the battery back to the auto parts store. Besides, imho, every Model A driver ought to know how to start his/her Model A with a hand crank.

Ok, a long post and probably more than most want to know about lead-acid batteries. At least I didn’t include the battery equations (once a submariner, always a submariner…)

Skip,

Very good information on the battery and most intersting to say the least.

Pluck
 
For a quick battery test turn on the headlights. With the lights on hit the starter. If the lights go out while pushing the starter you have a bad battery or battery connection.
 
If you are using a trickle charger as in a battery tender, overnight charging on a dead battery, it isn't enough to charge it.
 
Skip's explination is great, but if you do add distilled water when you buy it at the store be sure that it says that it was produced buy "steam distillation". The reverse osmosis process dosen't remove all of the minerals from the water.
 
I use a Milton battery tester that will load test the battery thru a resistor to ckeck for a poor cell.As has been said,see if the engine will turn with the crank.If starter is stuck,I find that it seems to work better if I rock the car in high gear rather than 2nd-but whatever works!As long as there is any voltage in the battery,they will usually start with the crank.When I have run engines on a stand & not had a battery handy I have used a 6V lantern battery & the hand crank.You also have to use a jumper wire from output terminal on generator to ground to prevent damage to gen when no chargable battery is in the circuit.
 
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