Greasing Bolts

[iwaters]

Whilst changing my brake pads recently I had a bit of trouble with one of the caliper bolts which had siezed in the caliper housing, the head became rounded. I eventually got it out by heating the caliper and tapping the bolt out with a hammer. When I replaced the new bolts I put some copper grease on the bolt thread and the underside of the bolt head.

I was wondering should I put grease on all bolt threads when replacing bolts? Are there any instances when I shouldn't use grease on threads?

 

[JohnD]

I use copper grease on all threads (except stainless where you can get a special grey anti-seize spray)

You need very little. To get it properly onto the threads I use a 50p toothbrush. the cost is insignificant and a tube or tub lasts for years.

If you are just sloshing it on with your finger, you put lube into the hole, not the bolt, otherwise it just rubs off when you screw it in.

I am more generous with it on exhaust fittings, as the grease burns away but leaves the copper powder to prevent seizing.

Remember to use locking nuts or washers to avoid the risk of things coming loose.

With wheel nuts, do not grease the dished surface on nut or wheel, which provides friction grip.

Be very sparing round brakes to avoid getting lube on the friction surfaces. On brake nipples and hose fittings you can moisten the thread with brake fluid, not grease.

 

[StephenW]

Also be careful with torque-sensitive bolts. Torque settings are usually specified for dry fittings so the addition of grease can mean that you overtighten them.

 

[timtheenchanter]

justy want to add torques are for CLEAN and dry threads, so make sure they are cleaned up before re-inserting, and no grease on these.

 

[Stivino]

Just want to add that Copaslip isn't a true grease, it's an anti sieze compund. It doesn't melt away either as it can withstand temperatures up to 1100°C and brakes shouldn't get anywhere near that.

 

[iwaters]

Hmmm, practically everypage in the workshop manual has a table detailing the torque settings for every bolt on that page. Don't think I'll be getting through my tub of grease very quickly!!!!!