Plusgas

larkim

Seen it referred to many a time, but I haven't got any. Though I do have some questions:-
- are there any materials that it "eats" (e.g. would using it on a stuck cartridge bearing in an aluminium cup with anodized paintwork causing anything to die?)
- do any high street shops sell it (none that I've found)
- are any of the other penetrating releasing agents good enough alternatives (so far I've tried GT85 as that's what I had to hand, but I've seend WD40 do a special pentrating product - http://www.halfords.com/motoring/engine ... rant-250ml )

Ta as ever!

The Rookie

GT85 and regular WD40 are not penetrating oils.

You'll get plusgas at most decent motorfactors, it doesn't 'eat' anything, I had to do some testing once for Ford for a particular issue and plusgas was the second best of the five products tested (the best was only available commercially).

For getting something stuck in place where its stuck due to aluminium oxide rather than rust, household ammonia is better (see Sheldon Brown).

larkim

Cheers, I did appreciate that GT85 wasn't a proper penetrating oil, it was either that or nothing so I thought I'd give it a go.

I don't know whether the oxidation is ferrous or alumnium, but I know I've got no ammonia at home (though I will take a look at that, thanks!).

Looks like MotorWorld on the way home will be getting a visit - would you get the tin of fluid or the aerosol spray? And would you literally submerge the relevant part in a bath of plusgas to get things shifted?

The Rookie

Aerosol, get the part warm if you can (even leaving in direct sunlight helps) and spray a little and often, different angles and then leave a puddle to soak into the joint.

larkim

Gave it a good soak all day, tested out a couple of taps and got some movement, so loooks like the plusgas did the job. Got it out with no damage, so all good. Thanks!

rockmonkeysc

Plusgas is corrosive to aluminium. We use it at work in one of our chemical resistance tests on new products. It's not half as aggressive as our salt spray test but I wouldn't use it on my bike.
All penetrating oils are corrosive, thats how they work.

larkim

Ah well, the deed is already done. TBH I don't know the specific metallic nature of the components, but what's done is done and there's no visible signs of damage.

rockmonkeysc

Regular exposure to plus gas will cause damage. A one off spray won't suddenly rot it.