Does WD40 eat rubber ?

paulsmith

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My brother has followed the advice of his boats builder and liberally coated the engine and its related parts with WD 40 applying a few squirts each time he uses the boat in order to keep everything in tip top order. The result is no rust and it all looks bright and in very good fettle.however the two front engine mount rubbers have completely perished and beyond what one would expect with age they have almost turned to crumbs whilst the back ones are fine. There hasn't been any diesel spillage onto the mounts so could it be the WD40.The clue seems to be that the back ones.beyond the reach of the spray are fine.any thoughts
 

BarryH

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I tend not to spray with WD anymore. If the mounts have been saturated with the WD then yes it can detiorate natural rubber. How old are they and how often did he spray them?

For coorrosion protection I use Wurth wax chain lube for motorcycles. Its keeps the chain on my bike looking new and is safe on rubber as M/c chaines have rubber O rings in the links. One application will last longer than and application of WD
 

alex_rogers

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Hydrocarbons will certainly attack natural rubber. Engine oil seals and o-rings are made of more exotic materials, such as Viton, in order to reset this effect. Don't know exactly what is in WD40, but it does seem to be the most likely explanation.
 

VicS

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According to the website WD40 is safe on rubber. The only materials which are mentioned as being affected are polycarbonate and clear polystyrene. However since it is a petoleum based product I would agree wth Alex Rogers and avoid contact with natural rubber.
 

Strathglass

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I don't know whether it damages rubber in marine applications.

But, I was strongly advised against using it or 'squezy' when assembling new rubber jointed domestic toilet drainage pipes as, in the long term this will damage the rubber.

The thing to use is the silicon oil intended to lubricate the rubber joints when assembling soil pipes which is available at builders merchants (Wickes sell it).

I imagine this would not damage expensive 'marine' rubber.

Iain
 

Alex_Blackwood

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Yes WD40 will eat rubber/rubber compounds, can't go into all the technicalities, don't know enough about that. However having had experience of the stuff since I first came across it in the late 60's I can say the following. It will destroy the above, including certain electrical insulating materials (HV spark plug leads). it will gunge up moving parts, it will form an insulating surface on low voltage contacts, giving trouble up to and including 110volt ac.
It is however quite a good corrosion inhibitor for metals. It is also quite effective (if expensive) as a release agent for rusted up nuts and bolts etc.
 

gjeffery

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Back in 1980, I used WD40 on a Jaeger LeCoultre speedometer from a rather wet Landrover. Fortunately my attempts failed and I took the speedo for repair. The technician who fixed (at very modest cost) it told me not to use WD40 again, because it disdolves the paint.
 

pampas

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Have found wd40 to be not much use for long term use, The best product that I have ever used is call Phospro but I cannot source it ( used a lot Deep-sea) the next is TF45 which contains Teflon, good for all uses and can be obtained in most Auto shops and does not attack rubbers, hope this info is of use.
 
A

Anonymous

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[ QUOTE ]
it will form an insulating surface on low voltage contacts, giving trouble up to and including 110volt ac.

[/ QUOTE ]Interesting - my bow thruster stopped working last week; the contactor was pulling in, but the motor wouldn't run. I was about to order a new contactor (£300) and played with the joystick a few times when it suddenly started working again intermittently then started to work perfectly after a half-dozen operations. I came to the conclusion that the contacts were soiled and that I had burnt off the contamination (I had assumed this to be oxidation). I had sprayed the whole area with WD40 last September/October so maybe that was the problem. I shan't do that again.
 

silvertop

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My understanding of WD40 is that it attracts dust and will do exactly that and form a covering of stick s---e, plays havoc with terminals. Great for damp-proofing casings, but i avoid using on low voltage electrical contacts.
 

Heckler

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NO
also the o rings in bike chains are not rubber so grease etc does not affect them.
i used to use liquid WD to wash brake slave cylinders and the washers with no ill effects, if any oil gets near the said items it makes them swell and disintegrate so WD does NOT affect rubber
stu
 
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Having made an agreement with local garage many years ago for help with my race car ... in return I would do odd-jobs around the workshops ... ended up sorting car electrics ... (met first wife that way - her ingition coil had given up the ghost !)
One of the first things I learnt was - WD40 gums up the electrics on cars if used too liberally ... used sparingly it can help disperse moisture and keep things going. Trick was to localise spray and not as many did .... spray all !! We had many cars in that suffered WD40 blues as we called it !!

I've heard that WD40 is a good easy-start for diesels - being kinder than ether ... dunno - never tried it.

Basically I only use WD40 as an easing agent - not liking release-oil as it dries out any joint etc. and affects any lubricant after.

WD40 .... used a little rarely .... as to eating rubber - any product with a petroleum component will have effect on rubber compounds ... as to extent depends on the compound.
 

tcm

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regardless of the effects of wd40, i'd be amazed if a squirt or several of wd 40 "destroyed" the engine mounts. For a start, they're big heavy lunks of rubber. Secondly, not all rubber is susceptible to petroleum attack, I mean, rubber tyres on cars drive over loads of fuel etc on roads and at petrol stations - but the tyres are ok.
 

Evadne

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WD40 is known to damage rubber (neoprene) in the connectors I use at work, the recommended lubricant is silicone spray or grease. I believe the problem is that the rubber will gradually absorb some of the hydrocarbon liquid and expand, breaking the metal to rubber joint. The neoprene also goes soft, but doesn't perish as you have described.
 

bluedragon

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If the engine mounts are natural rubber (or a synthetic equivalent) then this has very poor resistance to hydrocarbons and may well absorb large amounts of WD40 if regularly sprayed onto them. My observations of WD40 is that it has a volatile component probably to reduce viscosity for spraying...the resulting film seems to dry somewhat with time. It may well be this volatile hydrocarbon that is being easily absorbed into the rubber...and once there it's quite happy staying there!
 

Thistle

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Engine mounts are likely to be contaminated with hydrocarbons at some time. So why are they made of a material which will be damaged by hydrocarbons? Surely there are suitable alternative materials available.
 
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