Mil-Spec Battery Terminals 3/8 stud and 5/16 accessories

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Berzerker76

Berzerker76

Joined
Aug 27, 2016
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Location
Southern California
OK, so I was going to upgrade my battery post terminals to the Fastronix military style connectors.

Amazon.com: Fastronix Military Spec Battery Connectors- Positive Terminal: Automotive

My question is, to those of you that have gone this route, what was your solution for connecting the OEM fusible link which has 5/16 ring terminals to the 3/8 post that comes standard on these military style connectors? Did you crimp on new 3/8 rings to the fusible link? Did you use a 3/8 to 5/16 post adapter?

So far, I'm leaning towards something like this but thought I'd check with those of you with superior knowledge and experience before I go any further.

Battery Doctor Bolt, Brass, Brass, Positive/Negative 30600 | Zoro.com

Thanks in advance for any helpful input
 
There is enough substance in the connector to just ream it out to the correct size. DO NOT drill it out. The bit will grab the end of the connector and twist it to crap, ruining the fusible link. BTDT. I think I used a round file to slowly enlarge the hole and it's been perfect ever since.
 
Thanks for the info Drew. I had thought about drilling the link but was worried exactly what you described would happen. I think I have a reamer or round file laying around somewhere.
 
A pair of pliers to hold the eyelet and step bit worked well for opening up my fusible links.
 
bloc said:
A pair of pliers to hold the eyelet and step bit worked well for opening up my fusible links.
Click to expand...

Exactly what I tried and ruined a brand new and fresh out of the Toyota bag FL. I was so bummed at the time but chalked it up to lessons learned the hard way!
 
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I ended up using my Dremal rotary tool with a small metal cutting burr to enlarge the hole in the fusible link. You can lightly clamped the end of the fusible link in your vice, and then slowly ream out the hole.
 
Thanks for all the suggestions. I've decided to go the adapter bolt route, that gives me the option of connecting both 3/8 rings and 5/16 without chewing anything up.
 
I believe my fusible link ring is mounted on the clamp bolt of the military terminal. It's 5/16". There's a 5/16" and a 3/8" bolt on both the positive and negative mil-spec terminals. I drilled out my starter wire to 3/8 and put that on the other end. Slee makes some battery terminal extensions which would be the primo option IMO.
 
maxamillion2345 said:
:confused:
Get yourself a pair of dykes, cut one side of the ring terminal, lightly spread it out, put it over the bolt, tighten.
Click to expand...
PO left things pretty well MacGyvered up with electrical tape and shoddy butt connectors. Trying to get away from that, clean things up and do it right.
 
Shoredreamer said:
I believe my fusible link ring is mounted on the clamp bolt of the military terminal. It's 5/16". There's a 5/16" and a 3/8" bolt on both the positive and negative mil-spec terminals. I drilled out my starter wire to 3/8 and put that on the other end. Slee makes some battery terminal extensions which would be the primo option IMO.
Click to expand...
Duh, now I feel stupid.
 
A rat-tail file, that everyone should pack in the trail tool bag, does a dandy job in no time at all.
 
cruiserdan said:
A rat-tall file, that everyone should pack in the trail tool bag, does a dandy job in no time at all.
Click to expand...
I've got a whole mess of different files and wouldn't you know it, my rat tail is the only one I can't seem to locate at the moment. Bastard! (pun intended) Time to get organized…again.
 
Is that a mill bastard a smooth bastard?
:lol:
 
Why not remove bolt and replace with proper sized one? Seems I read some have done that here. I too screwed up a good link by trying to drill it out, and some said replace the bolt dummy.... or file/ream.
 
Have drilled three with no issues so far...
 
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