What is Selleys RP7, and where should you use it?

Selleys RP7 is a multi-purpose lubricating and penetrating spray that displaces water and inhibits corrosion. It does four jobs from one can: it loosens rusty and sticky parts, protects against rust and corrosion, cleans grime, adhesives, tar and gum, and works as a general lubricant to eliminate squeaks and keep mechanisms functioning smoothly.

The word that matters most in that description is penetrating. RP7 is designed to work its way into a seized or stiff joint rather than simply coat it, which is why the directions build in a waiting period rather than treating it as spray-and-go.

What the 5-minute penetration time means in practice

Selleys directs you to spray the affected area and allow approximately five minutes for penetration. That figure is the difference between the product working and appearing not to.

A seized nut is not seized on the surface — the corrosion binding it is in the threads, out of sight. Five minutes is the time the penetrant needs to travel into that gap. Reaching for the spanner ten seconds after spraying tests the strength of your wrist, not the product. If the joint does not free after the wait, Selleys' advice is to tap lightly if necessary, and to repeat the application in severe cases. A second dose with a second five-minute wait will usually do more than more force will.

Where to use it

• Nuts and bolts
• Mechanical parts and moving parts
• Seized or stiff joints

Beyond freeing seized fittings, Selleys lists three ongoing uses: protecting against rust and corrosion, cleaning grime, adhesives, tar and gum, and general lubrication to stop squeaks and keep mechanisms moving. Water displacement sits behind all of those — it is why the product is used on parts that have been wet, not just on parts that are stuck.

How to use it

1. Spray the affected area. On a seized or stiff joint, nut or bolt, direct the spray at the point where the two parts meet, since that is where the penetrant has to travel.
2. Allow approximately 5 minutes for penetration.
3. Tap lightly if necessary. Light tapping is the stated technique, not heavy hitting.
4. Repeat the application if needed in severe cases.

As a general lubricant, use it to eliminate squeaks and to keep mechanisms functioning smoothly.

Hazard classification

Classified as hazardous under Safe Work Australia GHS 7, with the signal word Danger.

• Aerosols — Category 1. H222: extremely flammable aerosol. H229: pressurised container, may burst if heated.
• Skin irritation — Category 2.
• Specific target organ toxicity, single exposure — Category 3, narcotic effects.

Dangerous Goods Class 2.1 (flammable gas) under the Australian Code for the Transport of Dangerous Goods by Road & Rail and New Zealand NZS 5433.

What is in it

Chemical entity	CAS number	Proportion (w/w)
Naphtha, petroleum, hydrodesulfurized heavy	64742-82-1	30–60%
Butane	106-97-8	10–30%
Propane	74-98-6	10–30%
Non-hazardous or below reporting limits	—	Balance

Butane and propane together make up 20–60% of the can. They are the propellant, and they are why a lubricant is classified as an extremely flammable aerosol. The penetrating oil itself is the heavy naphtha fraction.

The practical consequence is about where RP7 typically gets used: seized bolts, hinges, locks, electrical fittings and engine bays. Those jobs often involve heat, grinders, welding or live electrics nearby. Spray, then let the solvent flash off before you introduce any ignition source — the vapour is heavier than air and will sit in the cavity you just sprayed into.

Do not pierce or burn the can, even when empty, and do not store it above 50 °C or in direct sunlight — a car boot in summer exceeds that.

Protection

• Gloves — nitrile rubber for intermittent contact; assess against your own conditions.
• Eye protection — chemical goggles or safety glasses.
• Ventilation — use only in a well-ventilated area, with local exhaust where available, and a respirator where an inhalation risk remains. The vapour is heavier than air and collects in hollows; do not work in a confined space.
• Clothing — overalls and safety shoes. Wash hands before eating, drinking or smoking, and wash contaminated clothing before reuse.

First aid

Exposure	What to do
Eyes	Rinse cautiously with water for several minutes, removing contact lenses if present and easy to do, then keep rinsing. If irritation persists, get medical advice.
Skin	Wash with plenty of soap and water. Remove contaminated clothing and wash it before reuse. If irritation develops, get medical advice.
Inhalation	Move the person to fresh air, keep them at rest and warm. If effects persist, seek medical advice.
Swallowed	Do not induce vomiting. Rinse the mouth and seek medical advice immediately.

If poisoning occurs, contact a doctor or the Poisons Information Centre — 131 126 in Australia, 0800 764 766 in New Zealand — with the container to hand. Selleys emergency line: 1800 220 770 in Australia, 0800 220 770 in New Zealand.

Common questions about Selleys RP7

How long do I leave it before trying to undo a bolt?

Approximately five minutes, to let it penetrate. Then tap lightly if necessary.

What if the bolt still will not move?

Repeat the application. Selleys states that a repeat application may be needed in severe cases.

Does it stop rust?

It protects against rust and corrosion, and it inhibits corrosion — that is one of the product's stated functions alongside loosening parts that have already seized.

Will it get rid of sticky adhesive residue?

Cleaning grime, adhesives, tar and gum is one of its listed uses.

Can I use it on a squeaky hinge?

Yes. Selleys lists using RP7 as a general purpose lubricant to eliminate squeaks and keep mechanisms functioning smoothly.

Does it displace water?

Yes — it is described as a multi-purpose lubricating and penetrating spray that displaces water and inhibits corrosion.

Can I use it on moving machinery parts?

Mechanical parts and moving parts are listed uses.

Is this the same as RP7 Heavy Duty Degreaser?

No. Selleys RP7 Heavy Duty Degreaser is a separate product — a cleaner rather than a lubricant — with its own directions and its own limitations. The names are close enough that it is worth checking the label before you buy.

Is it a lubricant or a penetrant?

Both. Selleys describes it as a multi-purpose lubricating and penetrating spray, and lists general lubrication and freeing seized parts as separate uses.

What else is in the Selleys lubricants range?

Selleys Ezy Glide is the dry, non-oily lubricant for sliding mechanisms such as roller door tracks. The full range is in the lubricants section.