Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 03-24-2017, 07:09 PM   #1
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Keeps blowing fuse

Hey guys,
Im about to give up on this thing. I had the engine compartment apart to paint and put it back together, started it and cause I had the wire on the starter instead of the fuse part, the wires burnt up. I ordered new wires and installed them per the wiring diagram. Everytime I turn on my cutoff switch the fuse blows. I followed the paper and the wiring diagram. Any ideas? I added pictures
Attached Images
File Type: jpg 14903998749921096131891.jpg (40.7 KB, 246 views)
File Type: jpg 1490400054221231164829.jpg (38.4 KB, 238 views)
File Type: jpg 1490400100311-1325251449.jpg (48.0 KB, 224 views)
Model A Nick is offline   Reply With Quote
Old 03-24-2017, 07:33 PM   #2
Jim/GA
Senior Member
 
Jim/GA's Avatar
 
Join Date: May 2010
Location: Young Harris, GA
Posts: 1,615
Default Re: Keeps blowing fuse

Brake light switch.
__________________
Jim Cannon
"Have a Model A day!"
Jim/GA is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 03-24-2017, 07:33 PM   #3
Tom Wesenberg
Senior Member
 
Tom Wesenberg's Avatar
 
Join Date: May 2010
Location: Mpls, MN
Posts: 27,480
Default Re: Keeps blowing fuse

Your ammeter nut needs the black insulating cover, but for now it will probably have some clearance if you swap it with the other ammeter nut. Also make sure the small notch in the instrument panel, for the dash light wire, isn't cutting into the wire. The ammeter end of the dash light wire looks a little shaky also, so be sure it doesn't have a wire strand touching the conduit.
Tom Wesenberg is offline   Reply With Quote
Old 03-24-2017, 07:45 PM   #4
Mitch//pa
BANNED
 
Join Date: May 2010
Location: Bucks County, PA
Posts: 11,454
Default Re: Keeps blowing fuse

Everything ( the entire car) feeds from the junction box terminals... separate all your circuits there, then add them one at a time till the short comes back. Then youll know which direction to proceed using the diagram. . That being said also make sure the junction box stud / wire posts are not shorting out on the firewall very common..

Last edited by Mitch//pa; 03-24-2017 at 07:58 PM.
Mitch//pa is offline   Reply With Quote
Old 03-24-2017, 07:52 PM   #5
1955cj5
Senior Member
 
1955cj5's Avatar
 
Join Date: Apr 2015
Location: Boise, Idaho
Posts: 1,502
Default Re: Keeps blowing fuse

I'd also disconnect the generator feed wire at the cut-out to isolate the headlight harness and light switch...
__________________
Early '29 CCPU that had a 4-speed, but not any more.......in the family since '62
1955cj5 is offline   Reply With Quote
Old 03-24-2017, 08:44 PM   #6
MAG
Senior Member
 
MAG's Avatar
 
Join Date: May 2010
Location: Austin, Texas
Posts: 815
Default Re: Keeps blowing fuse

Sponsored Links (Register now to hide all advertisements)
Picture 2, Is that a shadow under the Red wire or is the short Black wire that should from from the connector box Driver side Post to Coil driver side (-)? If wired that way it looks, it will create a direct short through the ignition switch to the points in the dist. when they are closed and the fuse will blow.
__________________
I noticed the harder I work the luckier I get!
MAG is offline   Reply With Quote
Old 03-24-2017, 10:05 PM   #7
1crosscut
Senior Member
 
1crosscut's Avatar
 
Join Date: Feb 2011
Location: Lincoln, Nebraska
Posts: 1,537
Default Re: Keeps blowing fuse

I'm betting on the junction box studs grounding out against the firewall. Disconnect all the wires and using a voltage meter check for continuity between the studs and ground.
__________________
Dave / Lincoln Nebraska

It'll feel better when it quits hurting.
1crosscut is offline   Reply With Quote
Old 03-24-2017, 10:16 PM   #8
Mike V. Florida
Senior Member
 
Mike V. Florida's Avatar
 
Join Date: May 2010
Location: South Florida
Posts: 14,052
Send a message via AIM to Mike V. Florida
Default Re: Keeps blowing fuse

Do what Mitch says. My guess is the dash light.
__________________
What's right about America is that although we have a mess of problems, we have great capacity - intellect and resources - to do some thing about them. - Henry Ford II
Mike V. Florida is offline   Reply With Quote
Old 03-25-2017, 06:10 AM   #9
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

OK, so I took it apart and started putting one wire at a time on to the box and the last wire shorted it out. The black striped one that goes to the cut out box on the generator. I have the headlights off the car, but I do have the end taped up separate from each other. I took the dash light wire off as well. I guess it needs the cutoff switch, or do the headlights need to be plugged in?
Model A Nick is offline   Reply With Quote
Old 03-25-2017, 06:17 AM   #10
Mitch//pa
BANNED
 
Join Date: May 2010
Location: Bucks County, PA
Posts: 11,454
Default Re: Keeps blowing fuse

Do you have The yellow wires connected to the cutout terminal shown on the diagram? They feed the horn and light switch.. if so remove those and leave the yellow / black from the terminal box connected. If the short goes away keep following the diagram

A couple common sore spots are inside the light switch, stop light switch, and headlight connectors (but u mentioned those wires are taped up)

Last edited by Mitch//pa; 03-25-2017 at 06:34 AM.
Mitch//pa is offline   Reply With Quote
Old 03-25-2017, 07:12 AM   #11
Jim/GA
Senior Member
 
Jim/GA's Avatar
 
Join Date: May 2010
Location: Young Harris, GA
Posts: 1,615
Default Re: Keeps blowing fuse

Brake light switch.
__________________
Jim Cannon
"Have a Model A day!"
Jim/GA is offline   Reply With Quote
Old 03-25-2017, 07:45 AM   #12
Growley bear
Senior Member
 
Join Date: Apr 2012
Posts: 777
Default Re: Keeps blowing fuse

As Jim Cannon suggested; Joining MAFCA and a local club will connect you with a wealth of information and some of the sharpest Model A people around.
Good luck
Growley bear is offline   Reply With Quote
Old 03-25-2017, 08:05 AM   #13
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

OK, so I took the yellow wires off the cutout terminal and left the striped wire on, touched the striped wire to the junction block and it blew the fuse. So my guess is the cutout got messed up.
Model A Nick is offline   Reply With Quote
Old 03-25-2017, 08:09 AM   #14
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

Quote:
Originally Posted by Growley bear View Post
As Jim Cannon suggested; Joining MAFCA and a local club will connect you with a wealth of information and some of the sharpest Model A people around.
Good luck
I am a member of both clubs, just haven't joined a local chapter yet, as the closest one is a bit away. Once i get out there with it, I want too
Model A Nick is offline   Reply With Quote
Old 03-25-2017, 08:29 AM   #15
Mike
Senior Member
 
Mike's Avatar
 
Join Date: May 2010
Location: ASTON, PA.
Posts: 721
Default Re: Keeps blowing fuse

I am a life member of the DELAWARE VALLEY MODEL A FORD CLUB BASED In BENSALEM PA . We meet th first Thursday of each month
Mike is offline   Reply With Quote
Old 03-25-2017, 08:31 AM   #16
BILL WILLIAMSON
Senior Member
 
BILL WILLIAMSON's Avatar
 
Join Date: Dec 2010
Location: FRESNO, CA
Posts: 12,560
Default Re: Keeps blowing fuse

Sometimes the terminal screws on the cut-out are TOO long & ground out on the generator case. Remember, most good terminal pliers have a cutter, to shorten many standard sized screws.
Bill W.
__________________
"THE ASSISTANT GURU OF STUFF"
BILL WILLIAMSON is offline   Reply With Quote
Old 03-25-2017, 08:35 AM   #17
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

Quote:
Originally Posted by Mike View Post
I am a life member of the DELAWARE VALLEY MODEL A FORD CLUB BASED In BENSALEM PA . We meet th first Thursday of each month
It meets in bensalem? That's really close to me, would love to go to one
Model A Nick is offline   Reply With Quote
Old 03-25-2017, 10:08 AM   #18
Tom Wesenberg
Senior Member
 
Tom Wesenberg's Avatar
 
Join Date: May 2010
Location: Mpls, MN
Posts: 27,480
Default Re: Keeps blowing fuse

Stop blowing good fuses and just connect a test light, or 6 volt buzzer across the fuse terminals. When the light goes out you have found the short.
Tom Wesenberg is offline   Reply With Quote
Old 03-25-2017, 10:15 AM   #19
Mitch//pa
BANNED
 
Join Date: May 2010
Location: Bucks County, PA
Posts: 11,454
Default Re: Keeps blowing fuse

Well you eliminated the lighting / horn circuit ,,incld the brake light switch. Your cut out may have a bad insulator which is causing it to ground through to the case. I use the diode cutouts that the suppliers sell,, no moving parts to hang up. Read up on what a cutout does and how it operates using the search feature, its a very simple device. Others prefer the original style with moving parts. The engine can be ran without one just connect the two wires together and bypass it... remember to disconnect those two wires after shutting down or youll have a draw through the generator which will drain the battery....

Plus what tom mentioned above,,,, this should have been stated earlier... a testlight works good

Last edited by Mitch//pa; 03-25-2017 at 10:24 AM.
Mitch//pa is offline   Reply With Quote
Old 03-25-2017, 11:00 AM   #20
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

Thank you for all your help!
Model A Nick is offline   Reply With Quote
Old 03-25-2017, 01:03 PM   #21
Patrick L.
Senior Member
 
Patrick L.'s Avatar
 
Join Date: May 2010
Location: Upstate NY and western Florida
Posts: 6,140
Default Re: Keeps blowing fuse

A test light and wiring diagram are invaluable, about the best money you'll spend.

Sometimes the cutout terminal screws are a tad too long and will ground against the generator case. Just another place to look along with all the other good info.

Once you get into the headlight connectors, they are another place to be mindful of shorts. I tend to do away with those pesky little connectors.
Patrick L. is offline   Reply With Quote
Old 03-25-2017, 02:36 PM   #22
Tom Wesenberg
Senior Member
 
Tom Wesenberg's Avatar
 
Join Date: May 2010
Location: Mpls, MN
Posts: 27,480
Default Re: Keeps blowing fuse

There is another way to test for shorts without having to take anything apart. This is especially good for newer cars with more complex wiring. You clip a flasher and light bulb (in series) across the two fuse terminals. The short will make the bulb flash on and off. Then just take an inductive ammeter or compass and lay it along the wires. The needle will flicker until you go past the short.
Tom Wesenberg is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 03-25-2017, 02:48 PM   #23
cpf240
Senior Member
 
cpf240's Avatar
 
Join Date: Feb 2017
Location: Northern Idaho
Posts: 282
Default Re: Keeps blowing fuse

Quote:
Originally Posted by Tom Wesenberg View Post
There is another way to test for shorts without having to take anything apart. This is especially good for newer cars with more complex wiring. You clip a flasher and light bulb (in series) across the two fuse terminals. The short will make the bulb flash on and off. Then just take an inductive ammeter or compass and lay it along the wires. The needle will flicker until you go past the short.
Interesting idea... have not heard of that one!
cpf240 is offline   Reply With Quote
Old 03-25-2017, 02:55 PM   #24
Mitch//pa
BANNED
 
Join Date: May 2010
Location: Bucks County, PA
Posts: 11,454
Default Re: Keeps blowing fuse

Quote:
Originally Posted by Tom Wesenberg View Post
There is another way to test for shorts without having to take anything apart. This is especially good for newer cars with more complex wiring. You clip a flasher and light bulb (in series) across the two fuse terminals. The short will make the bulb flash on and off. Then just take an inductive ammeter or compass and lay it along the wires. The needle will flicker until you go past the short.
The needle will also point towards the short, showing you which way to follow the circuit. When you pass the short it will point in the opposite direction
Mitch//pa is offline   Reply With Quote
Old 03-25-2017, 07:45 PM   #25
BILL WILLIAMSON
Senior Member
 
BILL WILLIAMSON's Avatar
 
Join Date: Dec 2010
Location: FRESNO, CA
Posts: 12,560
Default Re: Keeps blowing fuse

Quote:
Originally Posted by Mitch//pa View Post
The needle will also point towards the short, showing you which way to follow the circuit. When you pass the short it will point in the opposite direction
I have an OOOOLD Snap-On meter for that purpose, it came with a dandy circuit breaker.
KDad
__________________
"THE ASSISTANT GURU OF STUFF"
BILL WILLIAMSON is offline   Reply With Quote
Old 03-25-2017, 07:45 PM   #26
Patrick L.
Senior Member
 
Patrick L.'s Avatar
 
Join Date: May 2010
Location: Upstate NY and western Florida
Posts: 6,140
Default Re: Keeps blowing fuse

Sponsored Links (Register now to hide all advertisements)
Quote:
Originally Posted by Tom Wesenberg View Post
There is another way to test for shorts without having to take anything apart. This is especially good for newer cars with more complex wiring. You clip a flasher and light bulb (in series) across the two fuse terminals. The short will make the bulb flash on and off. Then just take an inductive ammeter or compass and lay it along the wires. The needle will flicker until you go past the short.




Works well. Even thru body panels.
Patrick L. is offline   Reply With Quote
Old 03-25-2017, 07:55 PM   #27
Mitch//pa
BANNED
 
Join Date: May 2010
Location: Bucks County, PA
Posts: 11,454
Default Re: Keeps blowing fuse

My inductive meter has to be pretty much touching the harness to register.. i have an ultrasonic device that i use for going through panels , rugs etc...
Mitch//pa is offline   Reply With Quote
Old 03-25-2017, 07:57 PM   #28
Mitch//pa
BANNED
 
Join Date: May 2010
Location: Bucks County, PA
Posts: 11,454
Default Re: Keeps blowing fuse

Quote:
Originally Posted by BILL WILLIAMSON View Post
I have an OOOOLD Snap-On meter for that purpose, it came with a dandy circuit breaker.
KDad
Maybe you can post a pic of that... i would like to see it

It might be in your safe if you cant find it
Mitch//pa is offline   Reply With Quote
Old 03-26-2017, 10:07 AM   #29
BILL WILLIAMSON
Senior Member
 
BILL WILLIAMSON's Avatar
 
Join Date: Dec 2010
Location: FRESNO, CA
Posts: 12,560
Default Re: Keeps blowing fuse

Quote:
Originally Posted by Mitch//pa View Post
Maybe you can post a pic of that... i would like to see it

It might be in your safe if you cant find it
I can't get to the garage to "discover" it
At one time, Snap-On discontinued them, as the circuit breakers were mal-functioning & burning up LOOMS!
Once we were creating SHORTS, when screwing roof racks on Datsun wagons, a screw would penetrate the flat roof loom. We'd just run the circuit breaker for awhile & feel for a WARM screw head, take the screw out & NIP it shorter. I told you we were GOOD!!
We also created SHORTS when nailing down the carpet panels, with them SCREW TACKS! There was also a flat loom beneath them.
A new Guy installed a rack, TOO FAR back & the tailgate wouldn't open all the way, BOY, he wuz in HOT WATER!
KDad
__________________
"THE ASSISTANT GURU OF STUFF"

Last edited by BILL WILLIAMSON; 03-26-2017 at 10:19 AM.
BILL WILLIAMSON is offline   Reply With Quote
Old 03-26-2017, 11:27 AM   #30
jm29henry
Senior Member
 
jm29henry's Avatar
 
Join Date: Sep 2010
Location: michigan
Posts: 1,093
Default Re: Keeps blowing fuse

Did you get it fixed?
jm29henry is offline   Reply With Quote
Old 03-27-2017, 07:21 AM   #31
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

Quote:
Originally Posted by jm29henry View Post
Did you get it fixed?
I have it traced to the cutout, so a new one should be here tomorrow. Its like this car just wants to sit in the garage. I take one step forward and then 3 steps back.
Model A Nick is offline   Reply With Quote
Old 03-27-2017, 09:52 AM   #32
denniskliesen
Senior Member
 
denniskliesen's Avatar
 
Join Date: Nov 2016
Location: SoCal
Posts: 753
Default Re: Keeps blowing fuse

Check the terminals on your key switch. The harness I bought from one of the vendors had terminals that were too long from the ring hole and the insulation. The wire terminal was grounding out on the case of the key switch.
denniskliesen is offline   Reply With Quote
Old 03-27-2017, 10:09 AM   #33
Growley bear
Senior Member
 
Join Date: Apr 2012
Posts: 777
Default Re: Keeps blowing fuse

I don't know what amount of experience you have in the realm of automotive
service/maintenance. Electrical service and trouble shooting seems to be a hard one for lots of folks. It need not be though.
The main rule is to take the time to educate yourself about the way something works. If you don't know how it works, you can't fix it; if you do, it was an accident.
There are many people in MAFCA & RORD BARN who are very knowledgeable and there is usually someone in a local club who is willing to help.
The best approach to your problem is to check everything that you disturbed while working on the car. You are on the right track by checking one thing at a time. It seems odd that if the cutout was operating properly that it would develop a short without some outside help. Usually when the contact points stick in the cutout, the ammeter shows a distinct discharge and draws the battery down. As with all things mechanical though there is always the exception.
Do you have a wiring diagram? The model A diagram is easy to follow with just a basic understanding of automotive electricity and schematic symbols.
It ain't rocket science and if your Model A is close to bone stock your problem is probably is nothing new; except maybe to you.
Sorry for the dissertation, just trying to help.
Good luck and keep us posted
Growley bear is offline   Reply With Quote
Old 03-28-2017, 07:13 AM   #34
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

Quote:
Originally Posted by Growley bear View Post
I don't know what amount of experience you have in the realm of automotive
service/maintenance. Electrical service and trouble shooting seems to be a hard one for lots of folks. It need not be though.
The main rule is to take the time to educate yourself about the way something works. If you don't know how it works, you can't fix it; if you do, it was an accident.
There are many people in MAFCA & RORD BARN who are very knowledgeable and there is usually someone in a local club who is willing to help.
The best approach to your problem is to check everything that you disturbed while working on the car. You are on the right track by checking one thing at a time. It seems odd that if the cutout was operating properly that it would develop a short without some outside help. Usually when the contact points stick in the cutout, the ammeter shows a distinct discharge and draws the battery down. As with all things mechanical though there is always the exception.
Do you have a wiring diagram? The model A diagram is easy to follow with just a basic understanding of automotive electricity and schematic symbols.
It ain't rocket science and if your Model A is close to bone stock your problem is probably is nothing new; except maybe to you.
Sorry for the dissertation, just trying to help.
Good luck and keep us posted
I was the outside help, LOL! it was def pegged to the discharge when it was running, so the cutout should be here today and I will hook it up one wire at a time. I hope I can finally put it all back together and start enjoying it. Thanks!!
Model A Nick is offline   Reply With Quote
Old 03-29-2017, 10:33 AM   #35
Growley bear
Senior Member
 
Join Date: Apr 2012
Posts: 777
Default Re: Keeps blowing fuse

Did you try bypassing the cutout? You can do that with a jumper wire 10/12 ga. Don't run the engine with the generator disconnected, no need of that.
Growley bear is offline   Reply With Quote
Old 03-29-2017, 11:28 AM   #36
jrelliott
Senior Member
 
jrelliott's Avatar
 
Join Date: May 2010
Location: Pine, AZ
Posts: 701
Default Re: Keeps blowing fuse

Let us know if the new cutout worked. Again look to see if the screw on the cut out terminal feeding the car is touching the case of the generator.
jrelliott is offline   Reply With Quote
Old 03-29-2017, 12:50 PM   #37
Model A Nick
Member
 
Model A Nick's Avatar
 
Join Date: Jan 2017
Location: Fairless Hills, Pa
Posts: 30
Default Re: Keeps blowing fuse

Quote:
Originally Posted by jrelliott View Post
Let us know if the new cutout worked. Again look to see if the screw on the cut out terminal feeding the car is touching the case of the generator.
I am my own worst enemy sometimes, the new cutout did not work as i had the bolt,rubber washer, then the wire against the cutout. So once i looked at my pictures and after pulling my hair out, I put the wire the correct way, bolt, wire then washer, everything worked as it should. And there was nothing wrong with the original cutout
Model A Nick is offline   Reply With Quote
Old 03-29-2017, 01:25 PM   #38
1955cj5
Senior Member
 
1955cj5's Avatar
 
Join Date: Apr 2015
Location: Boise, Idaho
Posts: 1,502
Default Re: Keeps blowing fuse

Now you have a spare!
__________________
Early '29 CCPU that had a 4-speed, but not any more.......in the family since '62
1955cj5 is offline   Reply With Quote
Old 03-30-2017, 07:40 AM   #39
Growley bear
Senior Member
 
Join Date: Apr 2012
Posts: 777
Default Re: Keeps blowing fuse

Great job; Lesson learned.
Growley bear is offline   Reply With Quote
Old 03-30-2017, 08:22 AM   #40
Patrick L.
Senior Member
 
Patrick L.'s Avatar
 
Join Date: May 2010
Location: Upstate NY and western Florida
Posts: 6,140
Default Re: Keeps blowing fuse

I am my own worst enemy sometimes
end quote


Hmm, aren't we all. We all have our brain farts every now and again.
Patrick L. is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 01:11 PM.