The Ford Barn

SP_51-F1 · 06-12-2013, 04:55 PM

What size fuse should be used on a '50 3-speed w/ overdrive. Was running a 30amp, but it blew and I'm not sure if it's because it was the wrong amperage.

If 30amps is correct, quick ideas as to what could be causing it to pull to many amps?

I'm diagnosing this over the phone, Mom's on her way to Tahoe, so I can't just break out the multimeter and start chasing wires.

trainguy · 06-12-2013, 05:06 PM

30 amps is about right,the coil in the OD solonoid is the big current draw.

Mike51Merc · 06-12-2013, 05:28 PM

30 Amp fuse. Don't put a bigger one in. Find out why it blew.

charles in east texas · 06-12-2013, 05:28 PM

SP, tell Joyce to pull out the overdrive handle and drive it like a standard shift. Then find the trouble when she gets to Tahoe. Charles

SP_51-F1 · 06-12-2013, 05:34 PM

Thanks Charles, might just be what we have to do.
They have been fighting heat problems all the way, not just my Mom, and I was hoping she could use the OD to keep things a little cooler.

They are replacing the fuse and going to see how long it will go this time.

Planojc · 06-12-2013, 06:49 PM

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Since they are in Albuquerque, I would use the OD as much as possible until they get to high country. I heard the ign. timing was off which would account for the overheating problem.

Planojc · 06-12-2013, 06:50 PM

I have found many of the OD relays with loose connections at the input tab as well as the fuse holder. They are held in place by a brass rivet and over time the connection is minimized due to corrosion. On all my relays I clean the area and using a good flux and a big iron, solder all rivet connections, including the ones under the cover. Loose connections will blow a fuse.

joe 1950 · 06-12-2013, 07:03 PM

they have a 30 amp circuit breaker your can get from all most any parts store napa for sure has them, this is only putting a bandage on the problem, does it blow when it goes into o.d. or after a while of driving if no bare wires and no rivets loose its very poss.solinoid shorting out

SP_51-F1 · 06-12-2013, 08:13 PM

Thanks everyone, but she's going to leave it a EFV8 members garage and take it easy in a rental for the rest of the tour.

I think the timing was the heating problem too. Apparently however, even with a good fuse it was not kicking in to overdrive. I hope that means the solenoid is bad and nothing is wrong internally. Or the wire connection to it shorted it. I guess we'll see.

charles in east texas · 06-12-2013, 09:11 PM

Sorry to hear that. Driving in standard shift might make the car run cooler rather than in overdrive. Charles

Ross F-1 · 06-12-2013, 10:08 PM

It could be the solenoid pull-in coil is remaining on, instead of switching to the hold-in coil. The pull-in coil draws a lot more. I have a spare here in the Albuquerque area, if the EFV8 club member wants to contact me (I am familiar with some of the members).

SP_51-F1 · 06-13-2013, 10:41 AM

Thank you Ross, I'll let you know.

rotorwrench · 06-13-2013, 02:47 PM

A 30-amp fuse is a pretty big one. It usually takes a direct short to ground or a bad internal short in the solenoid to cause that.

Planojc · 06-13-2013, 03:37 PM

Repairing and calibrating electronic test equipment for 30 plus years, many times a piece of equipment would come in with a blown fuse. Most times there was a reason for it to blow, but many times you could just replace the fuse and for unknown reasons it would never blow again.

charles in east texas · 06-13-2013, 04:33 PM

Quote:

Originally Posted by Planojc

Repairing and calibrating electronic test equipment for 30 plus years, many times a piece of equipment would come in with a blown fuse. Most times there was a reason for it to blow, but many times you could just replace the fuse and for unknown reasons it would never blow again.

I agree with you John. That has happened to my overdrives before.
Chas

trainguy · 06-13-2013, 04:59 PM

The fuse on my 51 drove me crazy!! It didn't blo it would just stop working.I ended up soldering tyhe fuse clip, as mentioned above and cleaning the oxidation,no problems since.Your problem [as stated above] most likly is a short in the wiring or a malfunction of the sol holding circuit.The holding coil is controled by a set of points inside the sol. and can be cleaned by removing the cover.Phil

35fordtn · 06-13-2013, 05:18 PM

My 50 had a overdrive relay go bad and they are hard to find.. I have several friends who also had this problem

rotorwrench · 06-13-2013, 06:14 PM

The engine compartment wasn't the best choice for fuse placement in an open environment like that. Perhaps some silicon grease would keep the corrosion at bay.

donald1950 · 06-13-2013, 06:49 PM

also be sure that the wire from the relay to the solonoid is 10 ga or so. i had alot of fuse blowing and i discovered that some one had a 14 ga wire to the solonoid and the wire was getting hot from the current flow and causing alot more resistance.. replaced it with 10 ga and had no more problems..... don

52merc · 06-13-2013, 06:56 PM

the relays and solenoids are available new in either 6volt or 12

06-12-2013, 04:55 PM	#1
SP_51-F1 Junior Member Join Date: Oct 2010 Location: Central TX Posts: 23	3-speed w/overdrive fuse What size fuse should be used on a '50 3-speed w/ overdrive. Was running a 30amp, but it blew and I'm not sure if it's because it was the wrong amperage. If 30amps is correct, quick ideas as to what could be causing it to pull to many amps? I'm diagnosing this over the phone, Mom's on her way to Tahoe, so I can't just break out the multimeter and start chasing wires.

06-12-2013, 05:06 PM	#2
trainguy Senior Member Join Date: May 2010 Location: Lehighton Pa Posts: 1,085	Re: 3-speed w/overdrive fuse 30 amps is about right,the coil in the OD solonoid is the big current draw.

06-12-2013, 05:28 PM	#3
Mike51Merc Senior Member Join Date: May 2010 Location: Northeast Pennsylvania Posts: 1,582	Re: 3-speed w/overdrive fuse 30 Amp fuse. Don't put a bigger one in. Find out why it blew.

06-12-2013, 05:28 PM	#4
charles in east texas Senior Member Join Date: May 2010 Location: Winnsboro, Texas Posts: 463	Re: 3-speed w/overdrive fuse SP, tell Joyce to pull out the overdrive handle and drive it like a standard shift. Then find the trouble when she gets to Tahoe. Charles

06-12-2013, 05:34 PM	#5
SP_51-F1 Junior Member Join Date: Oct 2010 Location: Central TX Posts: 23	Re: 3-speed w/overdrive fuse Thanks Charles, might just be what we have to do. They have been fighting heat problems all the way, not just my Mom, and I was hoping she could use the OD to keep things a little cooler. They are replacing the fuse and going to see how long it will go this time.

06-12-2013, 06:49 PM	#6
Planojc Senior Member Join Date: May 2010 Location: Plano, Texas Posts: 1,121	Re: 3-speed w/overdrive fuse Sponsored Links (Register now to hide all advertisements) Since they are in Albuquerque, I would use the OD as much as possible until they get to high country. I heard the ign. timing was off which would account for the overheating problem.

06-12-2013, 06:50 PM	#7
Planojc Senior Member Join Date: May 2010 Location: Plano, Texas Posts: 1,121	Re: 3-speed w/overdrive fuse I have found many of the OD relays with loose connections at the input tab as well as the fuse holder. They are held in place by a brass rivet and over time the connection is minimized due to corrosion. On all my relays I clean the area and using a good flux and a big iron, solder all rivet connections, including the ones under the cover. Loose connections will blow a fuse.

06-12-2013, 07:03 PM	#8
joe 1950 Senior Member Join Date: Mar 2013 Location: Green Bay Wi Posts: 425	Re: 3-speed w/overdrive fuse they have a 30 amp circuit breaker your can get from all most any parts store napa for sure has them, this is only putting a bandage on the problem, does it blow when it goes into o.d. or after a while of driving if no bare wires and no rivets loose its very poss.solinoid shorting out

06-12-2013, 08:13 PM	#9
SP_51-F1 Junior Member Join Date: Oct 2010 Location: Central TX Posts: 23	Re: 3-speed w/overdrive fuse Thanks everyone, but she's going to leave it a EFV8 members garage and take it easy in a rental for the rest of the tour. I think the timing was the heating problem too. Apparently however, even with a good fuse it was not kicking in to overdrive. I hope that means the solenoid is bad and nothing is wrong internally. Or the wire connection to it shorted it. I guess we'll see.

06-12-2013, 09:11 PM	#10
charles in east texas Senior Member Join Date: May 2010 Location: Winnsboro, Texas Posts: 463	Re: 3-speed w/overdrive fuse Sorry to hear that. Driving in standard shift might make the car run cooler rather than in overdrive. Charles

06-12-2013, 10:08 PM	#11
Ross F-1 Senior Member Join Date: Nov 2010 Location: NM Posts: 2,443	Re: 3-speed w/overdrive fuse It could be the solenoid pull-in coil is remaining on, instead of switching to the hold-in coil. The pull-in coil draws a lot more. I have a spare here in the Albuquerque area, if the EFV8 club member wants to contact me (I am familiar with some of the members).

06-13-2013, 10:41 AM	#12
SP_51-F1 Junior Member Join Date: Oct 2010 Location: Central TX Posts: 23	Re: 3-speed w/overdrive fuse Thank you Ross, I'll let you know.

06-13-2013, 02:47 PM	#13
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 18,006	Re: 3-speed w/overdrive fuse A 30-amp fuse is a pretty big one. It usually takes a direct short to ground or a bad internal short in the solenoid to cause that.

06-13-2013, 03:37 PM	#14
Planojc Senior Member Join Date: May 2010 Location: Plano, Texas Posts: 1,121	Re: 3-speed w/overdrive fuse Repairing and calibrating electronic test equipment for 30 plus years, many times a piece of equipment would come in with a blown fuse. Most times there was a reason for it to blow, but many times you could just replace the fuse and for unknown reasons it would never blow again.

06-13-2013, 04:59 PM	#16
trainguy Senior Member Join Date: May 2010 Location: Lehighton Pa Posts: 1,085	Re: 3-speed w/overdrive fuse The fuse on my 51 drove me crazy!! It didn't blo it would just stop working.I ended up soldering tyhe fuse clip, as mentioned above and cleaning the oxidation,no problems since.Your problem [as stated above] most likly is a short in the wiring or a malfunction of the sol holding circuit.The holding coil is controled by a set of points inside the sol. and can be cleaned by removing the cover.Phil

06-13-2013, 05:18 PM	#17
35fordtn Senior Member Join Date: Aug 2010 Location: McMinnville, TN Posts: 2,468	Re: 3-speed w/overdrive fuse My 50 had a overdrive relay go bad and they are hard to find.. I have several friends who also had this problem

06-13-2013, 06:14 PM	#18
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 18,006	Re: 3-speed w/overdrive fuse The engine compartment wasn't the best choice for fuse placement in an open environment like that. Perhaps some silicon grease would keep the corrosion at bay.

06-13-2013, 06:49 PM	#19
donald1950 Senior Member Join Date: May 2010 Location: san antonio, texas Posts: 461	Re: 3-speed w/overdrive fuse also be sure that the wire from the relay to the solonoid is 10 ga or so. i had alot of fuse blowing and i discovered that some one had a 14 ga wire to the solonoid and the wire was getting hot from the current flow and causing alot more resistance.. replaced it with 10 ga and had no more problems..... don

06-13-2013, 06:56 PM	#20
52merc Senior Member Join Date: May 2010 Location: new zealand Posts: 1,054	Re: 3-speed w/overdrive fuse the relays and solenoids are available new in either 6volt or 12 __________________ trev,, whats life "TOUGH" whats tough ' LIFE"