Starting Problem
Forum rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
-
Topic author - Posts: 18
- Joined: Mon Jan 07, 2019 8:47 am
- First Name: Robert
- Last Name: Hoops
- * REQUIRED* Type and Year of Model Ts owned: 1922 Roadster, 1927 Touring
- Location: Burton,Texas
- MTFCA Number: 15877
- Board Member Since: 2005
Starting Problem
My 6-volt, group 1 battery won’t crank my ’27 touring. After an overnight charge, the battery measures 6.25 volts and it passes a load test. When I jump start it with a 12-volt battery, it starts right up. When running, the ammeter registers like it always has. I’m a bit suspicious of the foot operated starter switch but, where else should I be looking?
Thanks in advance.
Robert
Thanks in advance.
Robert
-
- Posts: 6463
- Joined: Fri Jan 04, 2019 9:37 pm
- First Name: Steve
- Last Name: Jelf
- * REQUIRED* Type and Year of Model Ts owned: 1923 touring and a few projects
- Location: Parkerfield, Kansas
- MTFCA Number: 16175
- MTFCI Number: 14758
- Board Member Since: 2007
- Contact:
Re: Starting Problem
Check grounds and other connections for clean metal-to-metal contacts and tightness. The switch could be your problem, but a weak connection is more likely. Do you have big enough cables?
The inevitable often happens.
1915 Runabout
1923 Touring
1915 Runabout
1923 Touring
-
Topic author - Posts: 18
- Joined: Mon Jan 07, 2019 8:47 am
- First Name: Robert
- Last Name: Hoops
- * REQUIRED* Type and Year of Model Ts owned: 1922 Roadster, 1927 Touring
- Location: Burton,Texas
- MTFCA Number: 15877
- Board Member Since: 2005
Re: Starting Problem
Thanks Steve.
I pulled off the battery to switch cable and saw that some of the insulation is worn off and that it has been shorting against the frame. I bought the car in 1989 so it has probably been doing this for a long time. I reinstalled it and hooked up my heavy-duty jumper cables to it and a hot 12-volt battery. It cranks that way like it should with a 6-volt battery. I never noticed a cranking problem before as it always started instantly or free started.
I plan to buy a new HD cable and cable support from Lang’s. I’m hoping that’s all it needs.
I pulled off the battery to switch cable and saw that some of the insulation is worn off and that it has been shorting against the frame. I bought the car in 1989 so it has probably been doing this for a long time. I reinstalled it and hooked up my heavy-duty jumper cables to it and a hot 12-volt battery. It cranks that way like it should with a 6-volt battery. I never noticed a cranking problem before as it always started instantly or free started.
I plan to buy a new HD cable and cable support from Lang’s. I’m hoping that’s all it needs.
-
- Posts: 344
- Joined: Sun Jan 06, 2019 6:57 pm
- First Name: John
- Last Name: Hunter
- * REQUIRED* Type and Year of Model Ts owned: 1926 Geelong Tourer
- Location: Blue Mountains, Australia
- Board Member Since: 2002
- Contact:
Re: Starting Problem
Measuring the voltage at each of the following points while the starter motor is cranking will narrow it down: Positive battery terminal, battery side of starter switch, motor side of starter switch, starter motor terminal. A less accurate test, if no meter is available, is to feel the all these connections after cranking - the warmer they are the higher the voltage drop. The braid from the negative battery terminal to chassis is another place voltage drop can be a problem; particularly the chassis connection. If the starter won't crank with at least 4.5V at its terminal, there could be a fault in the starter motor itself. Switching on the dash lamp and observing its brightness while cranking also gives an indication of the wiring and battery condition.
Clutch drag is also something to be wary of; if the engine is hard to turn by hand, it will also be difficult for the starter motor.
Clutch drag is also something to be wary of; if the engine is hard to turn by hand, it will also be difficult for the starter motor.
-
- Posts: 1436
- Joined: Tue Jan 08, 2019 12:22 am
- First Name: craig
- Last Name: leach
- * REQUIRED* Type and Year of Model Ts owned: 1919 Firetruck/1922 Speedster
- Location: Laveen Az
- MTFCA Number: 26647
Re: Starting Problem
Hi Robert,
Steve & John are correct. May I put in my two cents? If you have a infrared thermometer use it so you don't end up with a nut tattoo on one or more fingers. And Google how to ( voltage drop ) test a starter circuit you will find it a more accurate method. Good luck
Steve & John are correct. May I put in my two cents? If you have a infrared thermometer use it so you don't end up with a nut tattoo on one or more fingers. And Google how to ( voltage drop ) test a starter circuit you will find it a more accurate method. Good luck
-
- Posts: 638
- Joined: Mon Jan 07, 2019 7:40 am
- First Name: CHARLIE
- Last Name: BRANCA
- * REQUIRED* Type and Year of Model Ts owned: "27 Tudor / "23 Touring
- Location: Brick N.J.
- MTFCA Number: 28967
- Board Member Since: 2010
-
- Posts: 175
- Joined: Sun Jan 06, 2019 7:33 pm
- First Name: Neil
- Last Name: Martin
- * REQUIRED* Type and Year of Model Ts owned: 11 tourer 18 tourer 18 TT
- Location: Sydney Australia
Re: Starting Problem
C.B in N.J.
"lose it" What do you mean? There is a lot of Cirmil's in braided cable and it is very flexable. N.
"lose it" What do you mean? There is a lot of Cirmil's in braided cable and it is very flexable. N.
-
- Posts: 638
- Joined: Mon Jan 07, 2019 7:40 am
- First Name: CHARLIE
- Last Name: BRANCA
- * REQUIRED* Type and Year of Model Ts owned: "27 Tudor / "23 Touring
- Location: Brick N.J.
- MTFCA Number: 28967
- Board Member Since: 2010
Re: Starting Problem
I mean they go bad. Lots of resistance. They heat up because of it and even with good clean connections you'll still have a slow cranker. Experience talkin' here.
Forget everything you thought you knew.
-
- Posts: 106
- Joined: Thu Jan 10, 2019 8:38 pm
- First Name: John
- Last Name: Regan
- * REQUIRED* Type and Year of Model Ts owned: 1911 Open Runabout, 1911 Touring, 1912 Delivery Cars (2), 1915 Roadster, 1916 Roadster, 1923 Touring Car
- Location: St. Charles, IL
- MTFCA Number: 14725
- MTFCI Number: 77
- Board Member Since: 1999
Re: Starting Problem
This thread is rather confusing from start to finish. Here is what I mean.
A battery that was charged overnight and then measured with the battery charger just disconnected would measure higher than 6.25 - it would measure more like 6.8 or higher. It would then slowly (much later) drift back to 6.35 or so.
If the hot lead of the battery was touching the frame that would have ruined a good battery because a good battery would have likely welded itself there and melted by literally boiling and that is something you don't want to witness since the battery will be literally destroyed in a cloud of stink. You don't want to go anywhere near a battery that is melting since it is already ruined and you can only get hurt by it.
Check your digital voltmeter on your modern car battery after driving that car for awhile and notice that it will be in the 13V+ range for awhile after driving it since it will have been charging most of that time. Batteries are slow to change their voltage back to the quiescent voltage once charging has stopped. 6.25 is close to normal for a battery that is charged up and OFF the charger for a day.
The correct size cables for a 6V Model T system are designated as 1/0 which is way heavier than typical 12V modern cables which don't work on the T usually until the starter is rewound to become a 12V starter. That is really not a necessary modification for a T IMHO.
All connections starting at the frame and ending at the starter stud MUST be clean BRITE and TIGHT. A T is easy to turn over with a 6V starter that is on a car with good cables and a good foot switch.
Battery disconnect switch if installed is usually (or always) a problem which is why most of us don't use them.
The most accurate way to find out what part(s) are problematic is to crank the starter over with the ignition turned off. Do it long enough for the parts to warm up and then stop and run your hand over every connection starting at the frame ground bolt. Touch each cable connection and cable all the way to the starter stud. The hot points are the high resistance points and thus are the trouble places.
Good hunting.
A battery that was charged overnight and then measured with the battery charger just disconnected would measure higher than 6.25 - it would measure more like 6.8 or higher. It would then slowly (much later) drift back to 6.35 or so.
If the hot lead of the battery was touching the frame that would have ruined a good battery because a good battery would have likely welded itself there and melted by literally boiling and that is something you don't want to witness since the battery will be literally destroyed in a cloud of stink. You don't want to go anywhere near a battery that is melting since it is already ruined and you can only get hurt by it.
Check your digital voltmeter on your modern car battery after driving that car for awhile and notice that it will be in the 13V+ range for awhile after driving it since it will have been charging most of that time. Batteries are slow to change their voltage back to the quiescent voltage once charging has stopped. 6.25 is close to normal for a battery that is charged up and OFF the charger for a day.
The correct size cables for a 6V Model T system are designated as 1/0 which is way heavier than typical 12V modern cables which don't work on the T usually until the starter is rewound to become a 12V starter. That is really not a necessary modification for a T IMHO.
All connections starting at the frame and ending at the starter stud MUST be clean BRITE and TIGHT. A T is easy to turn over with a 6V starter that is on a car with good cables and a good foot switch.
Battery disconnect switch if installed is usually (or always) a problem which is why most of us don't use them.
The most accurate way to find out what part(s) are problematic is to crank the starter over with the ignition turned off. Do it long enough for the parts to warm up and then stop and run your hand over every connection starting at the frame ground bolt. Touch each cable connection and cable all the way to the starter stud. The hot points are the high resistance points and thus are the trouble places.
Good hunting.