Seized caliper bolts - breaker bar or impact gun?
Discussion
Excited to spend the afternoon changing all discs and pads on the car today..... first corner and absolutely everything is seized - disc retaining screws, caliper bolts, the lot 
Whats better for getting the caliper bolts to budge (big 10mm hex bolts) before I go an buy one - Handheld impact gun or a long breaker bar?
Cheers
Whats better for getting the caliper bolts to budge (big 10mm hex bolts) before I go an buy one - Handheld impact gun or a long breaker bar?
Cheers
Hard to say, but I'd think about access. Your breaker bar will have a certain amount of slack in it before it becomes useful, and if you're fighting caliper bolts with a car on jack stands you might not have enough room for the swing it needs. Similarly, a big impact might not fit in the space you've got between the calipers and engine/ suspension/ whatever.
I've got a 600mm ratchet with an adjustable-angle head that works quite well in those kind of situations.
I've got a 600mm ratchet with an adjustable-angle head that works quite well in those kind of situations.
E63eeeeee... said:
Hard to say, but I'd think about access. Your breaker bar will have a certain amount of slack in it before it becomes useful, and if you're fighting caliper bolts with a car on jack stands you might not have enough room for the swing it needs. Similarly, a big impact might not fit in the space you've got between the calipers and engine/ suspension/ whatever.
I've got a 600mm ratchet with an adjustable-angle head that works quite well in those kind of situations.
Plenty of room for a breaker bar so i think i'll go and grab a long one!! Can drill the rotor screws out I suppose if a screwdriver and hammer wont work eventually so maybe dont need the impact gun I've got a 600mm ratchet with an adjustable-angle head that works quite well in those kind of situations.
Krhuangbin said:
Plenty of room for a breaker bar so i think i'll go and grab a long one!! Can drill the rotor screws out I suppose if a screwdriver and hammer wont work eventually so maybe dont need the impact gun
Certainly starting with the cheaper solution is sensible. I bought a big impact, and 90+% of the use it gets is wheelnuts. 
Don't break bolts unless/until you have replacements in your hand.
The way to remove stuck bolts without breaking them is regular applications of penetrating oil and enough torque in both directions to start flexing them without getting to close to their limit, repeated every few hours over hours or days if necessary - and heat if that's practical.
The way to remove stuck bolts without breaking them is regular applications of penetrating oil and enough torque in both directions to start flexing them without getting to close to their limit, repeated every few hours over hours or days if necessary - and heat if that's practical.
A couple of tricks i've used on seized caliper bolts when it's hard to get enough leverage due space in the wheel arch...
Get the bolt head clean with WD40 and a wire brush so you can get good grip on the bolt faces. Use sockets that have a good tight fit on teh bolt else you risk rounding it. I find hex sockets better than the star sockets.
1) Tight fiting ring spanner/ratchet on the bolt and hit it with a 3lb lump hammer in the direction you want it to go. This rarely fails to move bolts.
2) Put the crappy scissor jack thing under the spanner/ratchet and jack the end up. Be ware that there can be a lot of tension on the spanner so keep your face/hands away as you jack up in case it comes off the bolt or something breaks.
Get the bolt head clean with WD40 and a wire brush so you can get good grip on the bolt faces. Use sockets that have a good tight fit on teh bolt else you risk rounding it. I find hex sockets better than the star sockets.
1) Tight fiting ring spanner/ratchet on the bolt and hit it with a 3lb lump hammer in the direction you want it to go. This rarely fails to move bolts.
2) Put the crappy scissor jack thing under the spanner/ratchet and jack the end up. Be ware that there can be a lot of tension on the spanner so keep your face/hands away as you jack up in case it comes off the bolt or something breaks.
gamefreaks said:
A couple of tricks i've used on seized caliper bolts when it's hard to get enough leverage due space in the wheel arch...
Get the bolt head clean with WD40 and a wire brush so you can get good grip on the bolt faces. Use sockets that have a good tight fit on teh bolt else you risk rounding it. I find hex sockets better than the star sockets.
1) Tight fiting ring spanner/ratchet on the bolt and hit it with a 3lb lump hammer in the direction you want it to go. This rarely fails to move bolts.
2) Put the crappy scissor jack thing under the spanner/ratchet and jack the end up. Be ware that there can be a lot of tension on the spanner so keep your face/hands away as you jack up in case it comes off the bolt or something breaks.
He's dealing with Allen bolts if I've read correctly.Get the bolt head clean with WD40 and a wire brush so you can get good grip on the bolt faces. Use sockets that have a good tight fit on teh bolt else you risk rounding it. I find hex sockets better than the star sockets.
1) Tight fiting ring spanner/ratchet on the bolt and hit it with a 3lb lump hammer in the direction you want it to go. This rarely fails to move bolts.
2) Put the crappy scissor jack thing under the spanner/ratchet and jack the end up. Be ware that there can be a lot of tension on the spanner so keep your face/hands away as you jack up in case it comes off the bolt or something breaks.
finlo said:
gamefreaks said:
A couple of tricks i've used on seized caliper bolts when it's hard to get enough leverage due space in the wheel arch...
Get the bolt head clean with WD40 and a wire brush so you can get good grip on the bolt faces. Use sockets that have a good tight fit on teh bolt else you risk rounding it. I find hex sockets better than the star sockets.
1) Tight fiting ring spanner/ratchet on the bolt and hit it with a 3lb lump hammer in the direction you want it to go. This rarely fails to move bolts.
2) Put the crappy scissor jack thing under the spanner/ratchet and jack the end up. Be ware that there can be a lot of tension on the spanner so keep your face/hands away as you jack up in case it comes off the bolt or something breaks.
He's dealing with Allen bolts if I've read correctly.Get the bolt head clean with WD40 and a wire brush so you can get good grip on the bolt faces. Use sockets that have a good tight fit on teh bolt else you risk rounding it. I find hex sockets better than the star sockets.
1) Tight fiting ring spanner/ratchet on the bolt and hit it with a 3lb lump hammer in the direction you want it to go. This rarely fails to move bolts.
2) Put the crappy scissor jack thing under the spanner/ratchet and jack the end up. Be ware that there can be a lot of tension on the spanner so keep your face/hands away as you jack up in case it comes off the bolt or something breaks.
Noted about the preparation of the head however - rounding one will be a headache too far!!
Plus Gas or similar proper penetrating oil, preferably sprayed on several times over several days before attempting to undo if can wait that long.
Not WD40.
I'm not a great fan of breaker bars, they're too thin and springy.
I use an old click type torque wrench that's over 2ft long and absolutely will not bend, you have total control and feel over what's going on at the business end.
Make sure you've dug all crud out of the depths of the Allen bolts, you want that socket as deep as possible, confess i really don't like Allen bolts on such parts.
I wouldn't expect it to undo them so if adjustable wouldn't give the gun full power or use very short bursts, but if you have a rattle gun and good Allen sockets no harm in letting the rattle gun loosen some of the rust hold before using the manual method.
Not WD40.
I'm not a great fan of breaker bars, they're too thin and springy.
I use an old click type torque wrench that's over 2ft long and absolutely will not bend, you have total control and feel over what's going on at the business end.
Make sure you've dug all crud out of the depths of the Allen bolts, you want that socket as deep as possible, confess i really don't like Allen bolts on such parts.
I wouldn't expect it to undo them so if adjustable wouldn't give the gun full power or use very short bursts, but if you have a rattle gun and good Allen sockets no harm in letting the rattle gun loosen some of the rust hold before using the manual method.
A couple of years ago I bought an add-on ratchet for my breaker bar and it's been a godsend at times. It's a chunky thing rather than a fine tooth ratchet but it gives many more opportunities to have the bar in a place to put some movement in the right direction. You can even get breaker bars with them built in now.
I've put my full weight on it with a 1m bar, so that's about 1200Nm, and it hasn't exploded or slipped.
I've put my full weight on it with a 1m bar, so that's about 1200Nm, and it hasn't exploded or slipped.
Plus one for GreenV8's advice above.
TIGHTEN the bolt before trying to loosen it.
As it comes out, if it begins to squeal, STOP. It may be about to break. Wind in again, apply more penetrator, wait before trying again.
And, WD40 is NOT a penetrator! they make one, but it's different to the usual goop.
John
TIGHTEN the bolt before trying to loosen it.
As it comes out, if it begins to squeal, STOP. It may be about to break. Wind in again, apply more penetrator, wait before trying again.
And, WD40 is NOT a penetrator! they make one, but it's different to the usual goop.
John
Got them off absolutely no issue with the breaker bar
The retaining screws were completely seized on all wheels (drilled out and threaded parts fell out.)
However all the discs were properly, seriously stuck to the hubs. Was hammering away on all of them pissing off the neighbours for about two hours and none of them budged!!!
Given up
The retaining screws were completely seized on all wheels (drilled out and threaded parts fell out.)
However all the discs were properly, seriously stuck to the hubs. Was hammering away on all of them pissing off the neighbours for about two hours and none of them budged!!!
Given up
Edited by Krhuangbin on Sunday 11th September 17:28
If they're properly stuck then a puller and lump hammer in combination will usually get them off without resorting to cutting. Be sure to leave a wheel mut loosely fitted to stop parts flying across the workshop. Drums/discs can bend far enough enough to store up a lot of mechanical energy.
I had a major issue removing the rear caliper bolts from my Evora, my 700nm Kielder rattle gun wouldn't look at them and with an 800mm breaker bar bending like a banana I was terrified of snapping it.
The judicious use of a mapp gas torch did the trick, that's when it became clear that the PO/mechanic had refitted them with red Loctite
The judicious use of a mapp gas torch did the trick, that's when it became clear that the PO/mechanic had refitted them with red Loctite
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