Hey there,

My '72 F-250 truck (auto, 5.9L V8) needs a battery replacement and new battery terminals. The battery is 8 years old, and the terminals are worn and stripped. The truck barely starts, particularly if it's really cold. If it's below freezing, forget it.

In fact, it's been averaging 15 degrees for the last month and a half. The truck sits because I just can't start it.

I bought a new battery and generic brass terminals. I'm no mechanic, but I want to replace the terminals myself.

I believe the terminals are original ... the wires enter the back corner of the terminal (90 degrees to the terminal) and look like they will have to be cut to be released from the terminal.

The replacement terminals expect a connection to the wire in the rear (tightens via 2 bolts/nuts) - from 6 to 2 gauge cables.

It appears to me I'm going to have to cut the cables from the terminals, then trim slightly less than an inch (half to three quarters of an inch) of the insulation and slide it into the terminals.

I know this is trivial stuff, but I'm just asking if there's anything I need to do, or if I need special instructions. The most mechanic work I've ever done is changing the oil & filters, change tires, etc.

Help is appreciated!

 

Terminals are the posts on the battery, are you referring to the cables? The Red + one connects the battery to the solenoid and the Black - to the engine.

Personally I prefer a two wire - cable that connects both to the engine and to the body for better grounding.

FWIW: I also prefer Red (hot) Black (not), to help me remember which is which at a glance.


John

 

Welcome to FTE

Brass terminals? What are you refering to? The battery cable ends? They weren't brass originally.

As John stated above, terminals are the posts on the battery.

I don't know of anything connected with the battery to be of brass.

The batteries (-) negative cable was factory installed on one of the right exhaust manifold bolts.

The positive cable (+) goes to the solenoid (starter relay), From there, is another (starter) cable to the starter.

Possible battery failure causes: The battery is hooked up backwards / The battery has insufficient cold cranking amps.
ALL Fords from 1956 are NEGATIVE ground.

6 volt battery cables are thick, 12 volt battery cables are thin.

Using 6 volt cables on a 12 volt battery will cause the starter to drag, and lead to battery failure within no time.

Ford batteries offered in F100/350's 1965/79: R22-F (45 amp) / R24-F (55 amp) / R27-F (70 amp) / R27-FA (80 amp).

All will fit in the same tray.

My recommendation: R27-F or R27-FA.

 

I was actually referring to the connector that fits onto the battery. The packaging on those refers to them as terminals, so I figured I was wrong in thinking this entire time the terminals were on the battery.

Anyway...

The ends of the wires need replacing, and I couldn't get them off the battery (they were stripped beyond belief) so I decided to replace the whole set of wires. I didn't check to see if they were 12-volt (good question). I couldn't connect the negative wire to the block because the hole is only 1/4" wide, but the ground "plug" (bolt) is 3/4". So I will need to exchange it.

This truck only has about 65,000 original miles on it and I'm trying to get it repaired, where needed, so it is like new. I've had the engine rebuilt with new parts, but I wish I could do more of it myself. I fix computers for a living, not cars.

 

6 volt cables are hard to find, most everything in this country is 12 volt, so that shouldn't be a large issue. I was not aware of the amp differences for the cables but it makes sense.

I didn't realize there were any 3/4" bolts on the engines. My ground cable is connected just under the alternator using the existing hole. The bolt itself is smaller that the head that you attach the wrench to.

It is not critical where on the block that the cable is attached to. Since the starter gets the largest electric flow the ground is generally close to it.

Find a bolt on the engine that will fit the hole, clean any grease or paint away on the block and connect it.


John

 

Why not just buy new cables? They are fairly inexpensive and don't need to be very long on your truck.

 

yup change the wires to,these truck are old and the wires turn green inside.

 

Thats OK. I think most of us here on this forum are not mechanics but we do know more than the average guy! I myself am a Millmen who gets to play around with wood all day!!
I just recently sent my truck to My mechanic to have him go over the truck and fix all the misc. Crap. I would be able to do all of the work but to me its worth it because of the lack of free time nowadays. Plus thats good insurance to keep it running and reliable!!!

 

this is not true,the larger 6v cable will carry more amperage which is what you want

as far as bolt on cable ends,terminals or what ever you like to call them are a problem waiting to happen

 

Hey there

I just replaced the cables. The problem I ran into was the negative wire. The head of the bolt on the block is 3/4", not the thread itself.

I couldn't find a wire that had a big enough hole for that bolt to pass through. I ended up cutting the original end on my old wire, cutting the small end of the new wire, and putting the old end on the new wire.

A sales person from one of the few auto stores in the area suggested I simply clip the side of the new connector and carefully spread the cable end. That didn't work... the engine block bolt just spread the connector and broke it before it was even hand tight. Huge difference in size. That's all anyone in the area had. That's why I cut the old connector off the old wire.

My only worry is that the thing keeping the copper wires connected to that old connector is carefully (and tightly wrapped) electrical wire. I laid the wire in the groove, but I think the original wire was designed for either smaller gauge wire, or thinner insulation. The new wire fit in the old connector, but not tight enough for the connector to wrap all the way around the wire (3/4 of the way). So I taped it.

I haven't tried cranking / starting it yet, but my dome lights, headlights and dashboard work fine.

Think I'm ok?

And yes, as I said, I'm certainly no mechanic. I fix computers and manage computer networks for a living. That, and web pages. I'm the techie in my workplace. But hey, gotta have my truck for my outdoor trips, camping, etc.

 

the ground doen't have to be placed under a head bolt,the battery cables normally have a 3/8 hole in them and can be put at about any bolt that size
if you didn't solder the end on you proby created a problem that will bite you dow the road

 

Well I know that the bolt on the block is a 3/4" head (not sure what the thread size is, but it's 2x larger than the new wire's original end), and I cannot find a connector big enough to fit the bolt in this area.

There is no ground wire that I can see... just a positive and negative coming off of the battery. I know some have extra grounds that come off the battery terminal wires and ground elsewhere, but this truck never had that (although the new cables I bought do, so I simply taped them over with electrical tape).

As long as it doesn't come lose, should I be okay? Is that the major issue? If I used a soldering iron to solder the connection, you think it would be fine?

 

I personally would just replace the whole cable. Easy to get to and cheap. Only thing I dont like is the new ones I bought from Autozone are no longer red. All their cables are black and come with a little sticker you put on it denoting pos. or neg.

 

I replace the whole cables, Most of the time its the corrosion inside the cable that case all of the problem. Some of the bigger parts houses can install the lugs. They have the large crimping tools or find an electriction with the tool. They use it to terminate wires feeding transformers. I prefer to solder them. Any wiring exposed to the elements will get corrosion if not done right.

Nember's I don't know where you got this but this is not true. You will have less voltage drop and carry more current with the larger cable. Amperage travels on the outside surface of the wire, the more strands the more amperage it can carry with out heating up.

 

I would replace the cable and put it under one of the 3/8 bolts (9/16 head) up around the front of engine or intake

I wouldn't doubt the cables autozone glorified wal mart)sells are generic fit'm all and not pos/neg specific

I don't care about color,I know which cable is which,I make all my cables and are black;made from welding lead