Seized Bolt

Double spaced lines are a pain to read

Hot air gun, tapping with a small hammer and plenty of patience

Proper penetrating fluid such as Plus Gas.

HTH -

Beat me too it !! yep plusgas, left overnight and it should be fine, WD40 well over rated in my opinion, plusgas for freeing stuff 3 in 1 spray for lubing most stuff, silicone spray for others :-)

I would be tempted to saw it off and replace it if theres room, if its that badly seized its doubtful you will be able to rescue it.

KinRsole submitted this idea :

Plus Gas is reputed to be the best.

Try tightening a little, that sometimes works.

Any heat/cold cycling will help, even boiling water and dry ice.

end of scale - an Acro prop that's been left out in the weather. I haven' t tried Plus Gas yet but it's going to be a bash with a big hammer job as it would need a pretty powerful heat source to make much impact.

Rob

Hi Kin, On my ole Honda Botormike I had this very problem and a rounded-off bolt head - I ended up drilling off the head of the bolt (centrepunched, drilled with bit the same-size-as-or-just-larger-than the minor diameter of the bolt thread until the head freed off, so I could remove the bolted-on-bit and get to the remains of the bolt with Large Mole Grip). As has been said, Plusgas or similar helps a lot, as do diesel and hydraulic fluid (both "wick" down the thread like a proper perpetrating oil ) - if you have real problems, drill through the (exact!) centre of the bolt and try an easy-out (DO NOT apply excessive torque - they tend to expand the remains of the bolt and make it even tighter, then snap leaving a piece or hardened tool steel in the hole... Bugger) and if it fails, *carefully* drill out to the minor diameter of the thread and pick out the remaining spiral of thread, run a matching tap through lubricated with white spirit (for aluminium alloys).

Now I just need to work out how to get the broken off end of a ball-drive allen key out of a bolt in my g/f's botormike's fork yoke, so I can change the blown fork seal...

HTH, Dave H. (The engineer former known as Homeless)

Impact driver - preferably a pneumatic one.

If you have access to an oxy-acetylene torch use a fine nozzle and heat just the bolt head for a bit before using the impact driver.

This sometimes works [at your own risk, try it on another bit first, no liability etc etc] Try to get hold of some aluminium ammonium sulphate (alum). Form a little well around the offending head. Mix up the alum and drop into the well [concentration unknown, sorry] It takes a while but the alum will dissolve the steel and leave the aluminium in tact. It is many many years since I last did this, but it worked. but BE CAREFUL otherwise you will have a pile of scrap on your hands HTH