WD 40 on car brakes, how screwed am I?

WD 40 on car brakes, how screwed am I?

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Discussion

DrRads

Original Poster:

1 posts

23 months

Saturday 18th July 2020
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I was cleaning mt car and came up with the bright idea to spray some wd40 in my brake disc and callipers (from outside), 2/3 sprays on each weel , and immediately dawned on me what I just did, I sprayed it with dish washing soapy hot water, let it sit for 10 minutes and rinsed it with cold water (garden hose). After that tested the brakes and seemed good. Then, I drove to halfords to get from brake cleaners (about 20 minutes/ 5 miles) and sprayed a 500ml can evenly on all 4 dics and pads. After an hour or so, I tested the car's braking and its snappy. No slips or anything, stops as well as it should. Ran my finger along the disc and not oily either. (got new brake pads a month ago). And now Im wondering if its still dangerous to drive, on monday, I need to drive about 200 miles on the motorway and not sure what to do.

No ideas for a name

1,413 posts

64 months

Saturday 18th July 2020
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DrRads said:
I was cleaning mt car and came up with the bright idea to spray some wd40 in my brake disc and callipers (from outside), 2/3 sprays on each weel , and immediately dawned on me what I just did, I sprayed it with dish washing soapy hot water, let it sit for 10 minutes and rinsed it with cold water (garden hose). After that tested the brakes and seemed good. Then, I drove to halfords to get from brake cleaners (about 20 minutes/ 5 miles) and sprayed a 500ml can evenly on all 4 dics and pads. After an hour or so, I tested the car's braking and its snappy. No slips or anything, stops as well as it should. Ran my finger along the disc and not oily either. (got new brake pads a month ago). And now Im wondering if its still dangerous to drive, on monday, I need to drive about 200 miles on the motorway and not sure what to do.
WD40 is designed to stop rockets going rusty. not tidy up brakes!

As long as it hasn't soaked in to the pads - which it shouldn't as you washed it off - it will all have burnt off by now.

Evoluzione

8,593 posts

221 months

Saturday 18th July 2020
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Thread for you here: https://www.pistonheads.com/gassing/topic.asp?h=0&...

If they work ok, they are ok. Try some 0/30 fully synthetic next time.

citizensm1th

8,371 posts

115 months

Saturday 18th July 2020
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oh mate i think you should play it safe and fit new pads and disks who knows what you could have done

you don't want to be that guy who appears in the news paper having run down a bunch of nuns because you got over excited with the wd40

Macneil

704 posts

58 months

Saturday 18th July 2020
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citizensm1th said:
oh mate i think you should play it safe and fit new pads and disks who knows what you could have done

you don't want to be that guy who appears in the news paper having run down a bunch of nuns because you got over excited with the wd40
Pads maybe, but discs will be ok surely?

underwhelmist

1,633 posts

112 months

Saturday 18th July 2020
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Whoosh!

DuraAce

4,016 posts

138 months

Saturday 18th July 2020
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I'd scrap the car. The whole thing will be contaminated beyond repair smile

Ridiculous thing to do - what were you thinking?

Just drive it. It'll be fine. Seek assistance from someone who knows what they are doing next time you have any bright ideas!

Pando99

57 posts

37 months

Saturday 18th July 2020
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Just drive it and move on

colin_p

3,566 posts

190 months

Saturday 18th July 2020
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Pando99 said:
Just drive it and move on
.....backwards in a fireball over the cliff having ricocheted off that large oak tree on the bend you couldn't slow down for.

A1VDY

3,575 posts

105 months

Saturday 18th July 2020
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You needn't even have bothered washing it off. First application of the brakes would have burnt it away..

Dont like rolls

3,798 posts

32 months

Saturday 18th July 2020
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You will be fine, all WD40 does is wash away any lubricant ....HATE the stuff.

rallycross

11,659 posts

215 months

Saturday 18th July 2020
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Had something similar last week one of the cars going out we put new brembo disks and pads on the front - a 2.0 smax nothing fast. The Brembos must have had some strange coating on them that the garage forgot or never thought to remove.

My driver brought it back from the garage to me and never said anything. Couple of days later Customer comes takes for a test drive says likes the car but brakes feel strange - I take it for a quick drive and there is zero bite from the front brakes and after a couple of hard stops it’s not getting any better and smoke is coming off the pads - close inspection the disks look to be coated in grease - never seen anything like it and the car just would not stop had no bite even with full pedal pressure.

Cleaned them up with brake cleaner and some emery paper on the pads but no user ruined the braking efficiency dangerous to use like that.


GreenV8S

29,319 posts

262 months

Saturday 18th July 2020
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rallycross said:
close inspection the disks look to be coated in grease - never seen anything like it
It's normal for discs to be shipped with a protective coating to prevent corrosion. Seems that in this case the fitter forgot to clean them before installation. A spray with brake cleaner followed by a wipe down is normally all it takes to clean them.

Dont like rolls

3,798 posts

32 months

Saturday 18th July 2020
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GreenV8S said:
rallycross said:
close inspection the disks look to be coated in grease - never seen anything like it
It's normal for discs to be shipped with a protective coating to prevent corrosion. Seems that in this case the fitter forgot to clean them before installation. A spray with brake cleaner followed by a wipe down is normally all it takes to clean them.
That really is very basic .....it even tells you in the instruction sheet (bit of paper) in the boxes......but who reads those !

thisisnotaspoon

177 posts

149 months

Sunday 19th July 2020
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GreenV8S said:
It's normal for discs to be shipped with a protective coating to prevent corrosion. Seems that in this case the fitter forgot to clean them before installation. A spray with brake cleaner followed by a wipe down is normally all it takes to clean them.
It's usually a thin coat of paint on the disks though. And the pads sometimes then have a coating designed to strip it off as fast as possible.

I have never seen brake disks shipped with protective grease!

Personally Ive always gone as far as clean gloves before handling the disks and then being sparing with the cleaner as a last step just to be sure. Watching some people empty cans of it you wonder how much anti seize theyre probably washing off the back of the pads and the hub onto the disk!

Dont like rolls

3,798 posts

32 months

Sunday 19th July 2020
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thisisnotaspoon said:
It's usually a thin coat of paint on the disks though. And the pads sometimes then have a coating designed to strip it off as fast as possible.

I have never seen brake disks shipped with protective grease!

Personally Ive always gone as far as clean gloves before handling the disks and then being sparing with the cleaner as a last step just to be sure. Watching some people empty cans of it you wonder how much anti seize theyre probably washing off the back of the pads and the hub onto the disk!
Not changed many disks then if you have not seen the "protective coating" on any (normally a thin wax based product, very few use "paint")

InitialDave

10,321 posts

97 months

Sunday 19th July 2020
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Yeah, it's usually either some anti corrosion waxy coating, or a chemical passivation type finish.


Skyedriver

14,131 posts

260 months

Tuesday 21st July 2020
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Can't believe anyone would actually do this. First post, I call troll

Benbay001

5,750 posts

135 months

Saturday 25th July 2020
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Skyedriver said:
Can't believe anyone would actually do this. First post, I call troll
Believe it!

When i was young (pre 16) me and a mate were cleaning my bicycle and after oiling my chain he went to do my disc!...

And then yesterday, i took a wheel off a workmates car to check pad thickness as it was an advisory on his previous MOT.

He goes "Ahh, whilst the tyre is off i can put some of this on the rest of it.." holding a bottle of tyre shine