I have FSIII calipers. Is it a good idea to use a flat metal file on surfaces the pads and caliper slide along? I.e. the two prongs coming from the wheel hub carrier. If so Is it a good idea to keep filing until it's nice smooth flat shiny metal? I plan to use Ceratec grease on these parts after cleaning up.

 

Also the Haynes manual makes no mention of greasing the sliding surfaces of the guide pins. I assume like with other braking systems these should be greased and the caliper should slide freely along the pins?

 

I made the horrible mistake of cross-threading the guide pin bolts on one side last time. Will be doing everything possible to avoid that again.

 

Many thanks.

No filing, just a wire brush.

The guide bolts, I scrub them clean with a green pad and brake cleaner, then apply some silicon grease as that stuff does not annoy the rubber gaitors/bellows that they pass/slide through.

8 minutes ago, rum4mo said:

The guide bolts, I scrub them clean with a green pad and brake cleaner, then apply some silicon grease as that stuff does not annoy the rubber gaitors/bellows that they pass/slide through.

 

Ceratec won't affect the rubber either, it's a PAG/PTFE based synthetic grease entirely suitable for this application.

The way I buy Ceratec it is quite dear, ie small tube from ECP, the silicon grease is a large tube saved from being thrown in the bin at work because it was a year old or so - I seem to save the Ceratec for the alloy wheels on my car only, I might eventually change to using the aluminium version of Copaslip - when I swop winter>summer wheels and tyres.

 

Edit:- seems that I missed "Ceratec" being mentioned in the opening posting!

Edited 6 May, 20197 yr by rum4mo

Reading FTW...

6 hours ago, anewman said:

Is it a good idea to use a flat metal file on surfaces the pads and caliper slide along

 

I do, gets you down to clean metal much more rapidly and efficiently than wire brushing.

 

With the guide pins, it's critical that the caliper is perfectly aligned with the threaded holes in the carrier (obviously), so a good way to proceed is to use your hex bit just between finger tips until the thread of the guide pin starts turning smoothly in.  If you need more torque on the bit than your fingers can manage, the alignment isn't good enough.

I wouldn't advise filing, you're accelerating wear on a tolerance designed to prevent the pads from fretting, the pads themselves move very little during braking and total travel over the lifetime of the pads is probably of the order 10mm per year, friction free movement is not necessary because the forces involved are very high indeed.

You're just bringing the surface back to how it was when manufactured, that's all.

It's quick and easy if you have a bit of skill.

Better to tickle the pad rather than the slider if it's tight, you'll be throwing the pads away at the next change anyway, if it's not tight then it doesn't need any attention other than a clean and grease.

Irrespective of skill level you're still removing metal that cannot be replaced, hence my advice.

Oh, I just remove rust. The original metal surface is much harder and very easily distinguished.