Stuck battery bolt

[Grahamm]

Having had battery problems, I bit the bullet and bought a new one, unfortunately when I tried to replace it today, I found that the bolt on the negative terminal is stuck solid

It has a Phillips head cross in the top, so I tried using that, but it started to sheer, so I decided to see if it would unbolt instead, however I've tried a 10mm socket which is too big and a 9mm which is too small.

I also tried a 3/8"  and 11/32" neither of which worked either, so I have *no* idea what the shop that replaced the old battery put on it (and they've now gone out of business!) and I really don't want to try pliers or molegrips as may round off entirely.

I've soaked it as best I can with what was left of a small can of WD-40 and I'm going to leave it overnight in the hope that it will loosen up, but if I'm going to get this new battery on it, I need some ideas in case that doesn't fix it.

Out of interest, the bolt on the positive terminal is ok and I've loosened it a bit, plus I've managed to remove the bolts holding the ABS relay etc and the clamp that holds the battery in place, so I'm thinking that if I can remove the positive lead (and then insulate it with eg a plastic bag and gaffer tape) I may be able to get the battery out of its holder to work on it a bit more easily.

The other issue is that there's connections for the heated gloves and the Sat Nav on there, so I can't simply rip things off.

As a last resort I may have to try to drill the bolt out, but I really don't want to do that unless really necessary, so I'd be obliged for any useful suggestions.

[snapper]

you normally get new nuts and bolts with a new battery i wouldnt worry about the old bolts if you have cut grind or sheer them off then bin them ,
 

[Skippernick]

Bet thats your problem Grahamm, a corroded connection!

[Doddsie]

A quick smear of vaseline on the new one should stop it happening again.

[Grahamm]

you normally get new nuts and bolts with a new battery i wouldnt worry about the old bolts if you have cut grind or sheer them off then bin them ,

Yes, there are new nuts and bolts, but the main problem is simply getting access to the bolt (and, as mentioned) there's the connections for the Sat Nav and Heated Gloves which I'd prefer not to destroy.

I may try the Dremmel tomorrow if it doesn't loosen up with the WD-40, if not, I think I'll have to drill it out.

[JoeRock]

Pair of mole grips done up very tightly is probably your best bet mate. If that doesn't work, drill. Unless you've an impact driver?

[esetest]

Cut the cable near the crimp and replace the crimp , either borrow a set of crimpers from a sparky mate or solder the crimp   on  , you can buy crimps from an electrical wholesalers  , and replace both bolts and nuts .

[Grahamm]

Pair of mole grips done up very tightly is probably your best bet mate.

Unfortunately there isn't really space to get the mole grips onto the bolt

Cut the cable near the crimp and replace the crimp

Ah! Thanks for reminding me I've got a set of crimpers 

I bought them years back when I replaced the rear light with an LED one and since then they've been residing in a box.

I'll have another crack at it in a while and see what results...

[Ebme Geek]

Go back to phillips screwdriver but before trying to turn it give it a couple of sharp taps on the top of the handle, helps it to dig back into the screw and may shock the joint a bit ?
 
Mole grips end on & very tight ?
 
Cut a slot across top with hack saw and use flat screwdriver ?
 
center punch and hammer on an end of a flat ?
 
Oh, drill it, but dont use drill any bigger than the threaded part, and you should not damage any of the crimps 

[alan sherman]

Ring spanner and phillips screwdriver combo.  If that doesn't work then drill the bolt.  The bolt is scrap anyway.

[Farjo]

"It has a Phillips head cross in the top, so I tried using that, but it started to sheer..."
Now I don't want to insult you, and I'm only posting this because I've made this mistake myself. But are you using a pozidriv screwdriver?

[Grahamm]

"It has a Phillips head cross in the top, so I tried using that, but it started to sheer..."
Now I don't want to insult you, and I'm only posting this because I've made this mistake myself. But are you using a pozidriv screwdriver?

Hmm, you may have a point(!) there, I thought the Phillips driver had the blunt tip, but I've just checked and it seems that the Pozidriv one is blunt and the Phillips one is pointy.

In any case, thank the gods for WD-40, after a bit of wiggling of the battery bracket I did manage to make enough space get the molegrips on the head and, after a little resistance, it started to unscrew.

Interestingly, even though there was a bit of corrosion on the head, it seems to have only been a patina and the rest of the bolt looked clean, so maybe the person who tightened it after they'd added the Optimate connector just did it up *really* tight.

Actually the Optimate came in useful for something else too, I couldn't get enough purchase on the battery to get it out of the holder, but then I had a brainwave and fixed the "clip-on" charging clamps from the Optimate onto the terminals and that let me lift it out

So anyway, now everything is back in place and it's running again, so thanks to everyone for their help and advice

[Skippernick]

 

[Simon.Pieman]

"It has a Phillips head cross in the top, so I tried using that, but it started to sheer..."
Now I don't want to insult you, and I'm only posting this because I've made this mistake myself. But are you using a pozidriv screwdriver?

Hmm, you may have a point(!) there, I thought the Phillips driver had the blunt tip, but I've just checked and it seems that the Pozidriv one is blunt and the Phillips one is pointy.

In any case, thank the gods for WD-40, after a bit of wiggling of the battery bracket I did manage to make enough space get the molegrips on the head and, after a little resistance, it started to unscrew.

Interestingly, even though there was a bit of corrosion on the head, it seems to have only been a patina and the rest of the bolt looked clean, so maybe the person who tightened it after they'd added the Optimate connector just did it up *really* tight.

Actually the Optimate came in useful for something else too, I couldn't get enough purchase on the battery to get it out of the holder, but then I had a brainwave and fixed the "clip-on" charging clamps from the Optimate onto the terminals and that let me lift it out

Before you install the new battery get  a strip of old bicycle inner tube and ductape a strip of it around the battery longways leaving two 4'' ends which you can use to haul out the battery. Fold the ends over the top of the battery and tape them together to keep them out of the way when you are done.

[Robbie8666]

Before you install the new battery get  a strip of old bicycle inner tube and ductape a strip of it around the battery longways leaving two 4'' ends which you can use to haul out the battery. Fold the ends over the top of the battery and tape them together to keep them out of the way when you are done.

I used a length of old rachet tape around mine! that & gaffer tape to keep it tiddly!! 

[locksmith]

We've all got an old bicycle inner tube hanging around

[robin78842]

I just use a pair of pliers on each terminal and pull it out.

[Grahamm]

Before you install the new battery get  a strip of old bicycle inner tube and ductape a strip of it around the battery longways leaving two 4'' ends which you can use to haul out the battery. Fold the ends over the top of the battery and tape them together to keep them out of the way when you are done.

NOW he tells me...

(Not least because I've got a few old inner tubes lying around which I may fix punctures on at some time if I can ever be bothered!)

Ah well, I'll remember that for next time