Trailing arm adjustment bolts

[AndrewJames]

Originally Posted by Ducati750cc

Yes a bit of heat works wonders.


I have an old BOC O series welding torch which is great for such situations, with a no.1 tip and using oxy acetylene or oxy propane with a no. 1 propane tip I have a small flame with a small plume and if used with care can get into some odd spots without damaging or heating other components.


However my fall back for heating stubborn nuts, bolts and so on where a flame will cause damage is to use my sons induction kit, not cheap but seeing a bolt, or nut glow at up to 800c in a few seconds and unscrew like a new one is amazing.

I've seen videos of those induction heaters. They look amazing in the promotional videos. I asked my friend who works in a garage if they had one. He said they thought about it but "decided it wasn't worth it" which I think translates to "they're expensive as expletive"

[Typhoon190]

Might be also worth having an 11/16" socket to hand which in just under 17.5mm. I would consider starting with this rather than 18mm.

[Ducati750cc]

Originally Posted by AndrewJames

I've seen videos of those induction heaters. They look amazing in the promotional videos. I asked my friend who works in a garage if they had one. He said they thought about it but "decided it wasn't worth it" which I think translates to "they're expensive as expletive"

I think my lads kit cost about £500-£600 or thereabouts, which isn't overly expensive for tools these days.


For tool and equipment purchases he still remembers the advice given to him by his old boss when setting out on his own, which was " Don't flinch at paying out for good tools, only two things to ask yourself, will they save me time, will they make me money." I think his kit has done both and was soon into profit.

[squire]

Originally Posted by Typhoon190

Might be also worth having an 11/16" socket to hand which in just under 17.5mm. I would consider starting with this rather than 18mm.

I should have one of those but only a standard multipoint one.

[SD1too]

Originally Posted by squire

Are the trailing arm adjustment bolts prone to shearing off when trying to undo them? Any advice welcome ...

No Martyn. I've just successfully removed all mine as follows:

• Clean the heads with a wire brush.
• Don't use a bi-hex (12 point) socket. Use an 18mm hexagon socket and you'll need a handle about 0.5 metres long because the torque setting is 100 Nm.
• If the socket appears not to fit, light tapping with a rubber mallet will persuade it (because you've just removed the flakes of rust from the bolt heads).

My bolts hadn't been removed for 22 years and the threads were bright metal with no corrosion whatsoever. I cleaned up and treated the remaining light surface rust on the heads and the shank behind which is only about 0.5 cm long.

Simon

[Mike Noc]

Well five out of six of mine came out but one refused to budge. I agree with Trikey and don't think they will shear off though.

Sadly although we use induction heaters at work I didn't have one to hand, and despite giving the bolt head a good soaking in Plus Gas, heating and then cooling using freezing rust loosening spray, a good hammering with a lump hammer and then a 3/4 breaker bar all it did was round off the bolt head.

Had to get the welder out and weld a large nut on the end of the bolt. The localised heat from the arc welder usually helps to free off the corrosion and after a bit more effort it finally came out.



You can see the corrosion on the bolt - the same position bolt on Mrs Noc's 75 is also refusing to move so maybe muck and road salt can get up behind it.



I didn't have a tap the right size so ground an old bolt down to clean the thread up.



Plenty of Copaslip used when the bolts went back in to ensure they come out easily next time round.






.

[squire]

Thanks for all the replies and tips, all the bolts now changed and a loose exhaust heat shield secured. Had to spend another £2.63 for a decent 18mm socket though but only two put up a bit of a fight before they finally shifted

Thanks again to all who replied and thanks to this forum.

Martyn