I posted a thread yesterday with my 1915 not starting on battery. I received several very helpful posts. Now let me bring you up to date and ask for help again. This car is in the final stages of a restoration that did not include an engine rebuild because the engine ran so well. So this morning I went out and tried to start the car (Crank only) on battery and it would not start. So I switched to mag and it started with one complete turn of the crank. I let it run for about 1 minute then switched it over to battery and the car continued to run. So I shut the car down to try to start it on battery again. It started in compression 14 times before I could get it in the right spot so it would not fire. I then cranked it and it started with a 1/4 turn on the crank. I drove the car out of my garage and went about my day. This was about 8 AM. Now fast forward to 4 PM and time to put the car away. You guessed it, it would not start on battery. I started on mag again and drove it back into the garage. When I shut it down I switched it on battery again and it started on compression 20 times before I could get it to a dead spot. Then it started on battery on the first turn. Does anyone have any idea why the car will not start on battery cold but once warmed up it could not act any better? Could it be I am not getting quite enough spark out of my battery when cold but the less than 12 volt spark is enough to start it once warmed up? Any thoughts?
Check the ignition switch on the coil box.
I have just the opposite issue with my 1927, which I'm told is due to the vaporizer. My car will not start by hand cold nor on mag, but will once the car is warmed up. The car fires up immediately cold using the starter, but once the car is warm and has sat for 5-10 minutes, it takes a few cranks to get it going again. I'm wondering if your battery doesn't have enough cold cranking amps to get it going. Where is your spark set? Mine is usually about five notches up from totally retarded. How about the throttle? About seven notches for my car. All are different and starting on battery may require a different adjustment of the spark and throttle than starting by hand.
A PURE guess:
It sort of sounds like there's an electrical connection that for some reason is thermally sensitive. Maybe a loose spot in the coil box that causes an open circuit when cold, but when things warm up the metal expands enough to close the circuit.
I think Bob is right. Ignition switch or related wiring is loose, worn or dirty. Take the switch plate off to see which it is.
I have a 1927 with a vaporizer and I find it will start from cold on battery after being choked. When it is warm I can hit the starter, pull out the choke and the car will crank forever until it finally starts, it won't start unless it's choked. Is this all because of the vaporizer ?
Randy Glowacki, Parsippany, NJ
Model T's are an updraft intake and as such you generally have to choke them if only slightly even when they are warm. T's typically do not start while you are holding the choke closed - they fire when the choke is "dropped" out. If you have electric start will can see this easily. One can pull the choke and step on the starter switch and the thing will never start till you drop the choke while you still have your foot on the starter switch. If you take your foot off the starter switch first before you drop the choke - the car will usually not start.
After you get the car started and switch to battery, try moving the spark lever up and down. Will it run when the lever is fully retarded? If it won't run in that position, the problem might be in your timer.
Thank you for the advise, especially about dropping the choke when starting warm. I will give it a try on Saturday.
Any chance your Battery and Mag wires are reversed in your switch??
Maybe I missed it but do your the coils buzz properly and strongly as you crank it over on battery? I would think if any coil (one at a time) set to buzz on battery you can trace the strength right to the plug and IT should continuously spark great out of the head,hot or cold . That's where I'd start. If coils seem weak or get nothing cold your Batt. current to the coil box is upset cold .Heat can change anything ,making things better or worse.
As Dave suggests finding out if there's spark when it won't start is your first item. Sounds like there won't be any though because it sounds like an electrical problem to me too. A test light would be extremely handy in diagnosing also as in: do you have batt voltage to the coil box when on batt.
I have a similar problem with a 26. I turn on the ignition switch to battery and the coils buzz, but when I depress the starter switch it sputters on battery, if it starts at all. When I switch to mag it runs smoothly. It won't start on crank. It will fire but by the time I get around to the spark lever or the ignition switch it conks out.
Well yesterday, I put the battery charger on it for about an hour and it would start on battery with either the starter or the crank. So I diagnosed the problem to be a low battery.
It could be that your battery just needs charging, or that you need a new battery. It could even be that the ignition switch is worn, or that a wire between the ignition switch and the battery cable is making a poor connection.
My advice would be first be sure the battery is fully charged. Then if the problem still exists, clean all the wire connections between the battery and the coil box. Then if it still exists, bypass the ignition switch and see if that fixes it. If so, your switch needs work.
When doing any work such as this, be sure not to accidently connect the battery to the magneto. When you bypass the ignition switch it might be a good idea to disconnect the magneto wire at the magneto plug, just to be sure. Another test of the ignition switch would be to reverse the connection and connect the battery to the magneto side of the switch, with the magneto disconnected. Then try starting on battery by turning the switch to magneto and see what happens.
The first thing I would check is if it has a Carquest battery, if so, that would be the problem. I have had bad experience with anything electrical produced for Carquest. The problem with Carquest batteries is that they will not hold a charge, their life expectancy in my experience is less than a year, and when they fail they will not hold a 12 volt charge for very long, so they will seem to be fine as long as the car is started soon after it has been run, but over night the voltage will drop. My thought on how to solve your problem is to remove the battery and run on mag, the less needed to make a car run, the better.