Foot starter button fire

Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration
Model T Ford Forum: Forum 2017: Foot starter button fire
Top of pagePrevious messageNext messageBottom of page Link to this message  By David Kriegel Mishawaka Indiana on Thursday, May 25, 2017 - 07:47 pm:

In previous posts I had been complaining of a rough running engine on battery but smooth running on magneto. (new coils plugs wires etc) When I hooked up a 12 volt battery to the 6 volt after starting, through the 6 volt battery engine runs fine therefore probable less than 6 volts getting to coils?? Well I hooked up the positive cable to the battery and got a big spark!! Well something is grounding. Looked under starter switch burned wood and wires! In summary current running through one of the two battery terminals through a 1/2 inch bolt holding the foot switch to the frame through a wood support block! Burned through!. Took apart switch, one of two terminals is loose. I intend in insulate both terminals under the foot switch as it contacts the support plate and try again tomorrow. Question, it seems the two brass pads on the switch hooked to the battery and starter should be insulated from the starter switch frame? Right?? I will try a plastic tube sleeve over the posts? burned wood block holding switch burned by bolt floor board burned


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dallas landers on Thursday, May 25, 2017 - 07:58 pm:

Whew!!! Close one David. Glad you found it.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Kriegel Mishawaka Indiana on Thursday, May 25, 2017 - 08:15 pm:

yup big parade Monday ! Got to get it running safe


Top of pagePrevious messageNext messageBottom of page Link to this message  By Allan Bennett - Australia on Thursday, May 25, 2017 - 11:56 pm:

David, the two terminals in the foot switch do need to be insulated from the mounting plate. Originals had a fibre washer above and below the plate and a smaller diameter one on the thread where it passes through the bracket.

Allan from down under.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John F. Regan on Friday, May 26, 2017 - 12:38 am:

I would NOT use plastic to insulate high current connections since the plastic can deform when warmed up and then melt and allow things to short together making for things getting really hot.


Top of pagePrevious messageNext messageBottom of page Link to this message  By John Noonan - Norton, MA. on Friday, May 26, 2017 - 01:00 am:

Could a fusible link inline between the battery and the starter prevent this? The fire so close to the battery is very disturbing.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Kriegel Mishawaka Indiana on Friday, May 26, 2017 - 06:36 am:

Allan thanks for the advice Also John thanks for non plastic I am going to the local hardware this AM to see what they have to repair rebuild switch


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill Harper - Keene, NH on Friday, May 26, 2017 - 10:18 am:

Hi David,

The great amount of charring suggests that your grounding problem and the resulting heat had been ongoing for quite some time. I really don't think that much damage could have occurred in only five minutes or so.

John Noonan is disturbed (above) by the fire so close to the battery. I am concerned for you with the proximity of the fuel tank.

Please follow John (Mr. Electricity) Regan's advise and avoid plastic insulators. Look for fiber washers as they are Much more heat resistant.

Please be safe!


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Menzies on Friday, May 26, 2017 - 11:06 am:

This is a typical starter switch, WHAT COULD POSSIBLY GO WRONG?


Top of pagePrevious messageNext messageBottom of page Link to this message  By john kuehn on Friday, May 26, 2017 - 12:53 pm:

Fiber washers will work if you can find them. You can modify them if you find some that need a little fit up or drilling. Some Ace hardware stores have them.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Dave Dufault on Friday, May 26, 2017 - 01:34 pm:

So, is this thread not a good reason to install a solenoid? I know that my heel does not always go "straight" down (not sure why, but a little "wiggle" with the heel helps to make u{contact} and get electricity to the starter.

It would seem that one of "Mr. Electricity's" fuses and a solenoid would be a beneficial add-on.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Menzies on Friday, May 26, 2017 - 02:28 pm:

The char pattern indicates the heat source was at least a foot from the switch assembly. There is also a trace image of a cable on the edge of the area of the greatest amount of char. It would appear that the battery cable was red hot on several occasions and not just this one time. When wood chars over time the ignition temperature of the wood is substantially reduced and will ignite at very low temperature (as low as 300 degrees) normally it takes about 700 degrees to achieve ignition. When applying the 12 volt battery to the 6 volt battery it is possible you increased the voltage to 18 volts. In my opinion applying 12 volts to a 6 volt battery is an unsafe practice. I have a 26 T and the magneto is not operating and I have run it on the battery for 30 years it starts and runs strong. Your problem does not appear to be the starter switch, however the battery cable looks very suspect.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Peter Claverie, Memphis TN on Friday, May 26, 2017 - 02:48 pm:

Re: a fusible link between the battery and solenoid: No fusible link that I've ever heard of will pass the amount of current needed to start the car, and still melt if there's a problem of the kind you experienced.

Now, a fuse between the starter switch and the low current wiring of the car is a very good idea. Usually 30 amps.

You're going to need new cables. I suggest you go to a parts house for over-the-road trucks (18 wheelers). They have the cable and the terminals, and can make them just the right length. You might want to slip some plastic tubing over the cable where it crosses a metal edge, just to make it safer. You might also want to tape the joint between the cable's insulation and the terminal, to keep out moisture.

Re: Solenoid: Yes, by all means. It takes the big load off of the 90+ year old switch, and introduces new, clean contact points to the system in place of old, pitted ones.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Peter Claverie, Memphis TN on Friday, May 26, 2017 - 05:31 pm:

P. S. Don't forget to also replace the cable from the battery's - terminal to the frame, and thoroughly clean the place where it attaches, and bolt it very tight (I use Grade 8 bolts), and use toothed lock washers on both ends of the bolt.

I have found it helps to get a modern 12 volt cable designed to go from a solenoid to a starter (terminals on both ends), and put it between a bolt on the engine and a bolt on the frame, thoroughly cleaning the contact points at both places. You'll be astounded how much better a 6 volt battery will spin a Model T engine with all these fixes in place! While a 12 volt cable isn't big enough to carry the amperage drawn by a 6 volt system, this extra cable only carries a portion of the current.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Jerry Davis Houston TX on Friday, May 26, 2017 - 05:57 pm:

David, I had a similar incident several years ago. Those old starter switches including the new repos carry all of the amp load of the starter. It's a recipe for a short circuit and fire. Do consider using a solenoid where the starter switch caries only the low amp circuit needed to close the solenoid. you can reuse either the old switch or leave it be and use a hidden push button if keeping originality is important. Just my thought.


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Kriegel Mishawaka Indiana on Friday, May 26, 2017 - 06:21 pm:

I have rebuilt the switch test for continuity tomorrow. Troubleshooting, past owner had secured foot switch via 8 inch bolts passed vertically through the starter plate, through a support wood block and secured to the car frame (GROUND) current worked through direct short to vertical bolts to frame burning away nearly completely the wood support block

If this fails tomorrow can you direct me to previous posts on installing a starter solenoid please


Top of pagePrevious messageNext messageBottom of page Link to this message  By Peter Claverie, Memphis TN on Friday, May 26, 2017 - 06:47 pm:

The solenoid is easy. You can go to Tractor Supply and get a solenoid for a Ford 8N or 9N tractor, or go to an auto parts house and get a solenoid for a 1930's Ford car or truck.

Make sure it's a 6 volt solenoid, and has a large connector on each of its two sides, and one small connector on the top.

The way it works is, it gets (+) juice from the incoming battery cable. You just have to connect the battery to the right one - it's usually marked with a + or something, but you can test it with an ohm meter between the top connector and each of the side ones. The one that shows any continuity at all is the Battery connector.

The internal magnet gets its (-) juice from the small terminal. You set it up so the floor button connects that little terminal to a ground (usually a mounting bolt). Any size wire will do.

When the (-) is applied to the little terminal, a big magnet inside pulls the contacts together, and the two large terminals are connected --- the starter gets juice! There's a pretty strong spring inside that separates the terminals instantly when juice goes away.

Mounting the solenoid is usually a matter of bolting it to the cross member just beneath where it sits. Orientation doesn't matter.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Scott Conger on Friday, May 26, 2017 - 09:16 pm:

David

buy two solenoids. That way when the first one fails on tour and no one else has a replacement to help you out, you can replace it with your spare, and be on your way in short order, rather than miss out touring while you hunt down a replacement at NAPA. I've seen this happen more times than I can count, when non-"T" parts fail. When something fails at an ice cream stop in the middle of nowhere, if a "T" part fails and you're with 50 other "T" owners, then you'll get 50 replacement parts. If you have a non-"T" part fail and are with 50 other "T" owners, you're still on your own.

Or, you can buy just 1 high-quality original style foot switch, keep your car original, and drive it another 20-30 years without a problem.


Add a Message


This is a private posting area. Only registered users and moderators may post messages here.
Username:  
Password:

Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration