Red and blue loctite on caliper bolts?

Red and blue loctite on caliper bolts?

Author
Discussion

Ian Geary

Original Poster:

5,010 posts

207 months

Sunday 9th February
quotequote all
Afternoon all,

I was looking over the front brakes on our 2007 swift, and wanted to take the calipers off to inspect the piston and sliding action.

It's a simple setup - you hold the slider with a 15mm spanner and the end bolt is 13mm.

However, on both sides, the top end bolt has blue loctite on it, and the lower bolt has red loctite on it.

I had never seen this before, and Google throws no light on this practice.

Has anyone seen this before? Or is able to share some insight maybe?

I would say the top bolt was definitely aluminium (blue) whereas the lower bolt was rustier so looked steel (red). Same size though.


I've done them both up with blue loctite, as I was out of red.


Thanks

Ian


Belle427

10,571 posts

248 months

Monday 10th February
quotequote all
I was under the impression it indicates the strength, blue for medium which can be easily taken apart with hand tools and red which required some heat.

Jaybmw

322 posts

96 months

Monday 10th February
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Someone been overally cautious. Absolutely no need for it

Rowe

386 posts

137 months

Monday 10th February
quotequote all
Some pad kits come with fresh hardware.
It's probably more likely that someone has at some point fitted a new bolt and re-used one of the old one (as opposed to applying two different grades of loctite)

E-bmw

11,050 posts

167 months

Monday 10th February
quotequote all
As others have said, it will likely be a case of all that was to hand, I wouldn't worry about it, it is not "a thing".

MattyD803

1,990 posts

80 months

Monday 10th February
quotequote all
Over the years, I've replaced brake pads on a number of cars (mostly Japanese) and the genuine manufacturer 'full' front pad kits come with replacement bolts, pre-coated with BLUE thread lock compound.

I've never seen or heard of red being used for these bolts - I'd suggest re-coating with blue only, red is unnecessary for this application in my experience. What is more important, is torquing up correctly on refitting.

Defcon5

6,393 posts

206 months

Monday 10th February
quotequote all
It’s an old gypsy trick.

TwinKam

3,333 posts

110 months

Monday 10th February
quotequote all
Some of my stocks of new caliper slide bolts; some with red, some with blue, some with neither.



No rhyme, no reason. Don't worry.

Ian Geary

Original Poster:

5,010 posts

207 months

Wednesday 12th February
quotequote all
Ok thanks all.

Just wondered as it seemed a bit odd.

It's probably a mechanic removing just one bolt to swing the caliper up to do brake pads, and using whatever bolts they had to hand to replace it.

The torque is pretty low on these bolts , so I see why the thread lock is important.


Ian

Chris32345

2,134 posts

77 months

Friday 14th February
quotequote all
Locktite is generally overkill for brakes but does add some peace of mind

darreni

4,203 posts

285 months

Friday 14th February
quotequote all
I don't use either on cailper fixings, just torque to recommended spec.
As a note, blue loctite is medium strength & allows fixings to be removable with hand tools, red loctite is usually permanent & requires 300C plus heat to remove. I'd never use red on anything that may require removal at a later date.


Ian Geary

Original Poster:

5,010 posts

207 months

Friday 14th February
quotequote all
Yeah I normally wouldn't use it on brake calipers - and only if the manual called for it. Bit given it was on these ones I thought I would treat them to the low strength stuff.


I've used the super strength stuff occasionally and it's twisted the heads of bolts rather than undo them - that has been thrown away.