Shinkers

Hello,

I usually use Isopropyl alcohol for cleaning most things on my bike, but I ran out and I have a quart of Denatured alcohol in my shop. Anyway, I needed to clean and re-lube my hub, so I swabbed it out with some Denatured alcohol and then reassembled.

My question is, does anybody know if Denatured alcohol will hurt rubbers or plastics? I know that Isopropyl can dry out rubbers, but I've never had too much of a problem using it. There's a rubber freehub seal that is in the hub shell that I serviced that would have gotten some of the Denatured alcohol on it and now I'm wondering if that's a big deal or not. I didn't really think twice about it at the time.

If it matters, this is the Klean Strip stuff which is about a 50/50 mix of ethanol and methanol according to the brand.

Thanks.

WizardOfBoz

So first, different rubber types will tolerate different solvents differently. https://www.marcorubber.com/o-ring-c...lity-chart.htm

I would expect methanol to be a little more aggressive than ethanol or propanol, but with modern rubbers is may not make a difference. Further, this was an acute exposure: most compatibility charts are addressing whether the rubber part can handle the solvent in a service type situation. So I think you're probably ok.

But you've done it. So monitor the seals. If they work and they continue to seal, you have your answer. If they leak, report back here: you'll know for sure something others don't.

woodcraft

I put some in a cheap plastic squeeze bottle & the plastic failed after a couple of months, but it was in the sun.

Doesn't quite answer your question, but this thread went in to detail on the chemistry:

https://www.bikeforums.net/bicycle-m...l-hydrate.html

sch

Isopropyl and methyl alcohols are both sold in plastic containers. One in my closet is ~30 yrs old. 10% Etoh in gasoline has been hazardous
to the health of pre-late 80s or so era gas engines which may have various gaskets and seals that do not tolerate persistent exposure to the
ethanol in the gas. However even susceptible rubbers are unlikely to be degraded by a brief cleaning exposure such as you describe and the
probability of the rubber seal being susceptible is low in any event.

leob1

BTW, alcohol is not a very effective degreaser.

wschruba

It is not, but it is effective at removing residues from cleaning.

DaveSSS 

Use mineral spirits or naptha for degreasing.

Crankycrank

I've had Kleen Strip DA swell and deform some rubber seals on my motorcycle brake system trying to clean off brake fluid so there are some rubbers that aren't safe. Just to be safe I would keep it away from anything other than metals.

fietsbob

The denatured is methanol and ethanol .. liquor is potable ethanol Methanol is distilled from methane..


before the internet we would use a test sample and find out if ... " Denatured alcohol will hurt rubbers or plastics", or not

by testing it.. on scrap pieces..

Shinkers

Seemed to work fine to clean up the ratchets in my hub, but I'm sure that are better degreasers out there.

I don't have a scrap piece of the exact rubber that DT is using in this hub, and before the internet I probably would have just used the DA and not thought about it.

Thanks to all who posted, I pulled the freehub off tonight to look at it, and everything still looks and feels the same. I'm going to chalk this up to a (potentially) dodged bullet and be more careful about what I use next time.

WizardOfBoz

Unless you are going to glue the surface. At that point, I'd start with min spirits. Then I'd use isopropanol. Alcohol is better as a final rinse as it doesn't leave an slight oil residue.

If you are degreasing to get old grease and dirt off before relubing, min spirits works great.