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 05-03-2020, 04:37 PM   #1
txmike
Senior Member
 
Join Date: Jun 2010
Location: DFW Area
Posts: 165
Default Fuse....

I am burning 30amp fuses like a kid eating candy.

I tried a 35amp fuse and at least get power to check on some other things like brakes lights etc

Am i setting myself up for a fire if I try to run it with a 35a?

thanks again
Mike

txmike is offline   Reply With Quote
Old 05-03-2020, 04:47 PM   #2
DNLs1930
Senior Member
 
DNLs1930's Avatar
 
Join Date: May 2019
Location: Fort Worth side of DFW
Posts: 171
Default Re: Fuse....

Quote:
Originally Posted by txmike View Post
I am burning 30amp fuses like a kid eating candy.

I tried a 35amp fuse and at least get power to check on some other things like brakes lights etc

Am i setting myself up for a fire if I try to run it with a 35a?

thanks again
Mike


YES YOU ARE

DO NOT increase the fuse size!!
DNLs1930 is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 05-03-2020, 05:07 PM   #3
txmike
Senior Member
 
Join Date: Jun 2010
Location: DFW Area
Posts: 165
Default Re: Fuse....

Thought so - thanks!
txmike is offline   Reply With Quote
Old 05-03-2020, 05:40 PM   #4
rotorwrench
Senior Member
 
rotorwrench's Avatar
 
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 16,371
Default Re: Fuse....

Disconnect all circuits from the known buss then reattach each one by one to see if one blows the fuse.

The model A has a simple system compared to later cars. A person can check each wire to ground with an ohms meter to see if there is a dead short. Wires that are close together can be checked for cross shorting also. A person can check a system out with no connection to the battery if they do it this way. Individual wires should be isolated to do the checks.

I use my multi meter a lot and I have lots of jumper leads of all different lengths to check out individual conductors. The lighting system is the most common culprit due to the amount of current conducted and the amount of separate lighting circuits. It's more simple if you only have one tail lamp since there are only two wires that follow the frame back to it. Headlamp wiring runs inside metal conduits and along the radiator so there are multiple places they can short plus the horn wire that is hot all the time.
rotorwrench is offline   Reply With Quote
Old 05-03-2020, 05:52 PM   #5
Jacksonlll
Senior Member
 
Jacksonlll's Avatar
 
Join Date: Jul 2012
Location: Michigan-- Member of Oakleaf of MARC
Posts: 1,686
Send a message via ICQ to Jacksonlll
Default Re: Fuse....

Start by disconnecting your light circuit at the generator. If that clears it up, go after that circuit.
Jacksonlll is offline   Reply With Quote
Old 05-03-2020, 06:04 PM   #6
Patrick L.
Senior Member
 
Patrick L.'s Avatar
 
Join Date: May 2010
Location: Largo Florida
Posts: 7,225
Default Re: Fuse....

Sponsored Links (Register now to hide all advertisements)
I agree. As mentioned, I wouldn't recommend a 35 amp fuse. As said, isolate the circuits and see which has the problem. Since you didn't mention anything in particular I'm thinking its something like headlights, horn or brake switch feed..
Patrick L. is offline   Reply With Quote
Old 05-03-2020, 10:55 PM   #7
eagle
Senior Member
 
eagle's Avatar
 
Join Date: Aug 2011
Location: Eagle Bend, MN
Posts: 2,025
Default Re: Fuse....

Get yourself a 5 volt buzzer. Put that in series with the battery, it should buzz. Then start disconnecting things until the buzz stops. There's your trouble.
__________________
"There are some that can destroy an anvil with a teaspoon and shouldn't be allowed to touch anything resembling a tool."
eagle is offline   Reply With Quote
Old 05-04-2020, 02:06 AM   #8
Tom Endy
Senior Member
 
Tom Endy's Avatar
 
Join Date: May 2010
Location: Southern California
Posts: 3,122
Default Re: Fuse....

It may be that you have a poor ground on the battery that is allowing the generator voltage to run wild. Check the connection of the ground strap to the frame. It is out of sight and may have been neglected for years and become corroded and supplying a poor ground.

Remove the battery to access the cable. Remove the cable from the frame and wire wheel the end along with the nut and bolt. Clean the mounting boss on the frame so that it is bright shinny metal. Also clean the power cable and the battery terminals.

Tom Endy
Tom Endy is online now   Reply With Quote
Old 05-04-2020, 12:06 PM   #9
txmike
Senior Member
 
Join Date: Jun 2010
Location: DFW Area
Posts: 165
Default Re: Fuse....

Lots of great suggestions..... now off to the races and I will report back
thanks for the help
Mike
txmike is offline   Reply With Quote
Old 05-04-2020, 02:18 PM   #10
txmike
Senior Member
 
Join Date: Jun 2010
Location: DFW Area
Posts: 165
Default Re: Fuse....

I appreciate the advice. Now that you tell me i understand better but when it comes to wiring and positive/negative etc I am not the guy you want doing your work.

I disconnected wires and believe it is something to do with the starter switch. I believe pictures are worth a 1000 words. Take a look at the pics...

When you look at the rear of my switch you see three connections and two screws on the side that look like ground wire hookup? I have two wires. One red and one black with a blue connector. Hook up the red - no issue. When I hook up the black wire i have a problem.... the fuse starts getting hot etc.
Are they on the wrong terminals?
Bad switch?
Does the switch need a ground wire?

Other pics are added just in case in attachment....
Attached Files
File Type: pdf test.pdf (330.9 KB, 115 views)
txmike is offline   Reply With Quote
Old 05-04-2020, 03:10 PM   #11
wmws
BANNED
 
Join Date: Feb 2013
Location: Coatesville, Pa
Posts: 719
Default Re: Fuse....

That black wire goes to the distributor through the armored cable. It is probably shorting on the armored cable housing.
wmws is offline   Reply With Quote
Old 05-04-2020, 07:03 PM   #12
CWPASADENA
Senior Member
 
CWPASADENA's Avatar
 
Join Date: May 2010
Location: PASADENA, CA
Posts: 1,882
Default Re: Fuse....

You have an aftermarket ignition switch.


Does this happen with the key only in the "on" position or all the time?


Did you just install the ignition switch , if not, what was going on when this started. Had you been doing other electrical work on the car?


As stated by WMWS, I suspect the black wire goes to the distributor and something is shorted in the distributor or the armored cable. if there is one.


If this happens no matter if the key is either in the OFF or ON position, I may be the switch itself. If it does not happen when the key is in the OFF position, there is a problem with the black wire or something inside the distributor itself.


My opinion,


Chris W.
CWPASADENA is offline   Reply With Quote
Old 05-04-2020, 09:23 PM   #13
txmike
Senior Member
 
Join Date: Jun 2010
Location: DFW Area
Posts: 165
Default Re: Fuse....

Thanks guys - i did not just install the switch.
i can order a new armored cable but while I am at it why not replace the ignition - right?

You mention "aftermarket"

Is there are particular type I should be seeking
txmike is offline   Reply With Quote
Old 05-05-2020, 08:18 AM   #14
rotorwrench
Senior Member
 
rotorwrench's Avatar
 
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 16,371
Default Re: Fuse....

If a person is going to install a conventional ignition switch, the system really should be modified to connect the distributor directly to the coil and install the power wire in the switch circuit like all the later cars from the model B on. The model A is one of the few cars that switched the breaker side of the ignition circuit through the armored cable of the electro-lock switch.

On the original model A vehicles, the coil was connected to power all the time but it was only hot when the breaker circuit was turned on.
rotorwrench is offline   Reply With Quote
Old 05-07-2020, 09:55 PM   #15
30Ford
Senior Member
 
Join Date: Jan 2012
Location: Eastern Canada NB
Posts: 166
Default Re: Fuse....

I had a grounded Amp meter
30Ford is offline   Reply With Quote
Old 05-07-2020, 10:36 PM   #16
Y-Blockhead
Senior Member
 
Y-Blockhead's Avatar
 
Join Date: Jul 2011
Location: Redondo Beach, CA
Posts: 5,817
Default Re: Fuse....

Quote:
Originally Posted by rotorwrench View Post
If a person is going to install a conventional ignition switch, the system really should be modified to connect the distributor directly to the coil and install the power wire in the switch circuit like all the later cars from the model B on. The model A is one of the few cars that switched the breaker side of the ignition circuit through the armored cable of the electro-lock switch.

On the original model A vehicles, the coil was connected to power all the time but it was only hot when the breaker circuit was turned on.
I agree 100%.
Y-Blockhead is offline   Reply With Quote
Old 05-09-2020, 07:42 AM   #17
old31
Senior Member
 
Join Date: Jan 2016
Posts: 2,088
Default Re: Fuse....

What is the advantage of wiring it the Model B way?
old31 is offline   Reply With Quote
Old 05-09-2020, 08:22 AM   #18
robert shreveport
Senior Member
 
Join Date: May 2010
Location: Shreveport,La.
Posts: 332
Default Re: Fuse....

Wiring harnesses are cheap. Maybe you’d like to start with a new one if yours is old.
robert shreveport is offline   Reply With Quote
Old 05-09-2020, 09:52 AM   #19
mach0415
Senior Member
 
mach0415's Avatar
 
Join Date: Jul 2011
Location: Chester, SC
Posts: 162
Default Re: Fuse....

I had a similar issue and found my horn wiring grounded as the leads to the brushes were touching the horn motor housing.
__________________
Thanks,
Mark in SC


"We the unwilling, led by the unknowing, are doing the impossible for the ungrateful." -- By society, who is still arguing over who said it.
mach0415 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 10:35 AM.