AI Summary

Product: Selleys Auto Fix Auto Sealant Brand: Selleys (DuluxGroup Pty Ltd) Category: Automotive Silicone Sealant Primary Use: A 100% neutral cure silicone sealant built for sealing, bonding, and waterproofing in automotive and caravan applications across mixed materials including glass, painted surfaces, fibreglass, most plastics, trim, and most rubbers.

Quick facts

Best for: Automotive and caravan sealing jobs involving mixed materials, vibration exposure, UV, salt spray, and temperature extremes
Key benefit: Neutral cure chemistry bonds safely to metal, paint, and sensitive substrates without releasing acetic acid or causing chemical damage during curing
Form factor: 100 mL hand-squeeze tube with cuttable nozzle; no caulking gun required
Application method: Cut nozzle at 45°, extrude in one continuous stroke, tool smooth within 5 minutes using a moistened gloved finger

Common questions this guide answers

Will this sealant damage painted surfaces or metal trim? → No — neutral cure chemistry releases no acetic acid, making it safe against paint, metal, and sensitive substrates
What surfaces is this sealant NOT compatible with? → Natural rubber, NBR (Nitrile Butadiene Rubber), and Chloroprene/Neoprene should be avoided
How long before the sealed area can be exposed to water or stress? → Full cure takes 24 hours at approximately 23°C and 50% relative humidity; keep the area undisturbed until then

Product overview

Selleys Auto Fix Auto Sealant is a 100% neutral cure silicone sealant built specifically for automotive and caravan applications. Manufactured by Selleys, a brand under DuluxGroup Pty Ltd, it forms waterproof, high-strength bonds across the full range of mixed materials found in vehicles and caravans — glass, painted surfaces, fibreglass, most plastics, trim, and most rubbers. The 100 mL tube is sized for precise application in the tight, curved spaces that automotive work demands.

What separates this from general-purpose silicones is its resistance profile. Automotive environments are hard on sealants: constant vibration, wide temperature swings, prolonged UV exposure, salt spray from road conditions, and repeated contact with detergents during washing. Selleys Auto Fix is engineered to handle all of these. It's a purpose-built product, not a general silicone pressed into service.

Technical specifications explained

Knowing the specifications helps you confirm this is the right product for the job and apply it with confidence.

Cure system: 100% neutral cure silicone

This sealant uses neutral cure chemistry. It doesn't release acetic acid — the vinegar smell associated with acetoxy-cure silicones — as it cures. In automotive work, that matters. Acetoxy-cure silicones can corrode metal components, damage certain plastics, and degrade some rubber compounds over time. Neutral cure silicone works safely against metal trim, painted surfaces, and sensitive substrates without any chemical attack during curing. You get a clean, reliable result without risking damage to surrounding materials.

Cure timeline

The product cures in three defined stages:

Skin time: 5 minutes — The surface begins to form a skin. Complete all tooling and smoothing before this point.
Dry to touch: 30 minutes — The outer surface is no longer tacky and won't transfer to contact surfaces.
Full cure: 24 hours — The sealant reaches its full mechanical and chemical properties. Keep the sealed area free from stress, water immersion, and load until this stage is complete.

These timings are based on standard conditions (approximately 23°C and 50% relative humidity). Cooler temperatures or lower humidity slow the cure. Warmer, more humid conditions speed it up.

Service temperature range: -40°C to 180°C

Tested to ASTM C1246:2017, this range reflects real-world automotive demands. Engine bay components, exhaust-adjacent areas, and surfaces exposed to direct sun in hot climates reach temperatures that cause inferior sealants to soften, flow, or lose adhesion. At the lower end, alpine winters or cold storage environments push materials toward brittleness. The -40°C lower limit keeps the cured sealant flexible and intact in cold conditions rather than cracked and compromised.

Finish: translucent

Once cured, the sealant dries to a translucent finish. For visible areas — around windscreens, window trims, or caravan body seams — this is a genuine advantage. A coloured or white sealant draws attention to the repair. Translucent blends with most surface colours and delivers a clean, professional result.

Volume: 100 mL tube

The 100 mL format is sized for targeted automotive work. It delivers enough product for multiple sealing tasks without the waste that comes with larger cartridge formats, which require a caulking gun and are genuinely difficult to reseal between uses.

Compatible surfaces

Selleys Auto Fix Auto Sealant bonds to the following surface types:

Glass — Including windscreens, side windows, and rear glass, for resealing trim channels or addressing sealing failures around glass edges.
Painted surfaces — The neutral cure system protects automotive paint from chemical attack, making it fully suitable for use directly against painted bodywork.
Fibreglass — Common in caravan construction and some automotive body panels, fibreglass is a fully compatible substrate.
Most plastics — Automotive interiors and exteriors use a wide variety of plastics. The product bonds to most, though testing on a small hidden area is a smart step with unfamiliar plastic types.
Trim — Interior and exterior trim pieces, which are often composites of plastic, rubber, and metal.
Most rubbers — Effective across the majority of rubber seals and gaskets found in automotive and caravan settings.

Surfaces to avoid

The product is explicitly not recommended for use on:

Natural rubber
NBR (Nitrile Butadiene Rubber)
Chloroprene / Neoprene

These rubber types can be chemically incompatible with silicone sealants, leading to adhesion breakdown or degradation of the rubber substrate. If you're unsure of the rubber compound in your application, consult the vehicle manufacturer's documentation or test on an inconspicuous area before committing to a full application.

Resistance properties

The formulation addresses the specific stressors of the automotive environment:

Waterproofing — Creates a sealed barrier against water ingress, protecting against rust, electrical faults, and interior damage in vehicles and caravans.
Vibration resistance — Vehicles subject sealed joints to constant low-frequency vibration from the engine, road surface, and drivetrain. Rigid sealants crack under this stress. The flexible, elastomeric nature of cured silicone accommodates movement without losing adhesion or integrity.
UV resistance — Prolonged sun exposure degrades many sealants, causing yellowing, cracking, and adhesion failure. UV resistance is non-negotiable for any externally visible or exposed application.
Weather resistance — Stands up to rain, humidity, and temperature cycling — the repeated expansion and contraction of materials as temperatures rise and fall.
Salt spray resistance — Relevant for coastal driving and road salt in colder regions, both of which accelerate corrosion and degrade lesser sealants.
Detergent resistance — Regular vehicle washing with detergent-based products won't compromise the integrity of the cured sealant.

Application instructions

Correct application unlocks the full performance of this product. Follow these steps and get it right the first time.

Surface preparation

Clean all surfaces thoroughly before application. Remove dirt, grease, oil, old sealant residue, and any loose material. Surfaces must be dry. Adhesion to contaminated or damp surfaces will be significantly reduced, regardless of the sealant's capabilities. A clean surface is the foundation of a lasting result.

Nozzle preparation

Cut the nozzle at a 45° angle. The size of the cut determines the bead width — a smaller cut produces a narrower bead for fine work; a larger cut produces a wider bead for gap filling. For most automotive trim and sealing tasks, a small-to-medium cut is the right call. The 45° angle lets you hold the nozzle at a comfortable angle while maintaining consistent contact with the surface.

Application

Extrude the sealant with steady, even pressure directly into the joint or onto the surface. Keep a consistent speed along the joint to produce a uniform bead. Stopping and starting creates uneven thickness and potential weak points — commit to a smooth, continuous stroke.

Tooling the bead

You have a 5-minute window from the time of application to smooth the bead. Use a gloved finger — latex or nitrile gloves work well — to press the sealant into the joint and smooth the surface. A smoothed bead achieves better contact with both surfaces, looks cleaner, and is less likely to trap dirt. Wetting the gloved finger lightly with water or a soap-water solution helps with smooth tooling and stops the sealant from sticking to the glove.

Curing

Allow the sealant to cure undisturbed. Keep the sealed area away from water, stress, and mechanical load for at least 24 hours. In cooler or drier conditions, allow additional time before putting the seal to work.

Storage and shelf life

Store the product in a cool, dry location away from direct sunlight and heat sources. Keep the tube sealed between uses — silicone sealants begin to cure on exposure to atmospheric moisture, and an unsealed tube will skin over and eventually become unusable. After use, clean the nozzle tip and replace the cap or seal the nozzle with tape.

Check the expiry date on the packaging before use. Out-of-date silicone sealant can produce incomplete cure, reduced adhesion, or abnormal skinning behaviour.

Safety considerations

Selleys Auto Fix Auto Sealant is a consumer-grade product. Standard precautions apply:

Ventilation — Work in a well-ventilated area. Neutral cure silicones don't release acetic acid, but the curing process produces small amounts of byproduct vapour. Good airflow matters, particularly in enclosed spaces such as vehicle interiors.
Skin contact — Avoid prolonged skin contact with uncured sealant. Wear gloves during application. Uncured silicone is stubborn to remove from skin — wipe it off promptly with a dry cloth before it skins.
Eye protection — Keep sealant away from eyes. If contact occurs, rinse thoroughly with water.
Removing uncured sealant — Uncured sealant lifts cleanly with a dry cloth or mineral spirits before it skins. Once cured, mechanical removal by cutting or scraping is required.

Refer to the product's Safety Data Sheet (SDS), available from Selleys, for complete hazard and first aid information.

Troubleshooting common issues

Sealant not adhering

The most common cause is inadequate surface preparation. Grease, oil, moisture, or old sealant residue blocks proper bonding. Strip back the sealant, clean the surface thoroughly, confirm it's dry, and reapply.

Sealant skinning too quickly

Warm temperatures and high humidity accelerate skin formation. In hot conditions, work in smaller sections and tool each section immediately after application rather than applying a long bead and returning to it.

Bead pulling away during tooling

This typically happens when too much pressure is applied during smoothing, or when the sealant has already started to skin. Work quickly and use a lightly moistened gloved finger for smooth, controlled results.

Incomplete cure after 24 hours

Check ambient conditions. Cold temperatures slow cure time significantly. Move the vehicle or component to a warmer environment where possible, or allow additional cure time. Confirm the product is within its use-by date.

Visible sealant on painted surfaces

Mask adjacent painted surfaces with automotive masking tape before application. Remove the tape immediately after tooling, before the sealant skins, for a sharp, clean edge.

Expert tips

Test on inconspicuous areas when working with unfamiliar plastics or rubbers. Despite broad compatibility, some specialty automotive materials may respond unexpectedly — a quick test protects your work.
Don't over-apply. A neat, consistent bead that fills the joint performs better than a large excess of sealant. More material doesn't improve the seal and makes a mess of the finish.
For caravan roof seams, remove all old sealant before reapplication. Applying over degraded existing sealant is a common cause of continued leaks — start clean.
Cold weather application: Bring the tube to room temperature before use in cold conditions. Cold silicone is stiffer and harder to extrude evenly. A tube at room temperature gives you full control over bead quality.
Joint movement: Silicone sealants accommodate joint movement through their elastomeric properties. For joints expected to flex significantly — around flexible trim panels, for example — ensure the bead has sufficient width and depth to move without tearing.

References

Selleys Auto Fix Auto Sealant – Official Product Page
Selleys Auto Fix Auto Sealant – Technical Data Sheet (DuluxGroup Pty Ltd, Version 1.0, Updated 10/12/2024) (Manufacturer documentation provided as source material for this guide)
ASTM C1246:2017 – Standard Test Method for Elastomeric Sealants Used in Exterior Wall Joints of Buildings Subjected to Cyclic Movement
DuluxGroup Pty Ltd – Selleys Brand Information

Frequently asked questions

What is Selleys Auto Fix Auto Sealant: A 100% neutral cure silicone sealant for automotive use

Who manufactures Selleys Auto Fix Auto Sealant: Selleys, a brand under DuluxGroup Pty Ltd

What volume does Selleys Auto Fix come in: 100 mL tube

What cure system does this sealant use: 100% neutral cure silicone

Does Selleys Auto Fix release acetic acid during curing: No

Does it smell like vinegar during curing: No, neutral cure produces no acetic acid odour

Can neutral cure silicone corrode metal: No, it is safe against metal surfaces

What is the skin time for Selleys Auto Fix: 5 minutes

What does skin time mean: The window to complete all tooling and smoothing

What is the dry-to-touch time: 30 minutes

What does dry to touch mean: Outer surface is no longer tacky

What is the full cure time: 24 hours

What conditions are the cure times based on: Approximately 23°C and 50% relative humidity

Does cooler temperature slow the cure: Yes

Does higher humidity accelerate the cure: Yes

What is the minimum service temperature: -40°C

What is the maximum service temperature: 180°C

What standard was the temperature range tested to: ASTM C1246:2017

What does the sealant look like once cured: Translucent finish

Why is a translucent finish beneficial: It blends with most surface colours for a clean result

Does this sealant bond to glass: Yes

Does it bond to painted surfaces: Yes

Does neutral cure protect automotive paint: Yes, no chemical attack during curing

Does it bond to fibreglass: Yes

Does it bond to most plastics: Yes

Should you test on unfamiliar plastics first: Yes, test on a small hidden area

Does it bond to trim: Yes, interior and exterior trim

Does it bond to most rubbers: Yes

Is it suitable for natural rubber: No

Is it suitable for NBR (Nitrile Butadiene Rubber): No

Is it suitable for Neoprene/Chloroprene: No

Is it waterproof: Yes

Is it resistant to vibration: Yes

Why does it resist vibration: Cured silicone is flexible and elastomeric

Is it UV resistant: Yes

Is it weather resistant: Yes

Is it resistant to salt spray: Yes

Is it resistant to detergents: Yes

Is it suitable for caravan applications: Yes

Is it suitable for engine bay use: Yes, rated to 180°C

Must surfaces be clean before application: Yes

Must surfaces be dry before application: Yes

What happens if you apply it to a greasy surface: Adhesion will be significantly reduced

At what angle should the nozzle be cut: 45°

What does the nozzle cut size determine: The width of the sealant bead

How long do you have to tool the bead after application: 5 minutes

What should you use to smooth the bead: A gloved finger

What type of gloves work for tooling: Latex or nitrile gloves

What helps prevent sealant sticking to the glove during tooling: Lightly wetting the glove with water or soap-water solution

Should you apply the bead in one continuous stroke: Yes, for uniform thickness

How long should the sealed area be kept undisturbed: At least 24 hours

Should the seal be exposed to water before full cure: No

Can you use Selleys Auto Fix without a caulking gun: Yes, it is a hand-squeeze tube

Is the 100 mL format resealable between uses: Yes, with cap or tape over nozzle

How should the product be stored: Cool, dry location away from sunlight and heat

What happens if the tube is left unsealed: Sealant will skin over and become unusable

Should you check the expiry date before use: Yes

What can out-of-date sealant cause: Incomplete cure, reduced adhesion, or abnormal skinning

What is the most common cause of adhesion failure: Inadequate surface preparation

What causes the sealant to skin too quickly: Warm temperatures and high humidity

What should you do in hot conditions to avoid skinning: Work in smaller sections

What causes the bead to pull away during tooling: Excessive pressure or sealant already starting to skin

What should you do if cure is incomplete after 24 hours: Allow additional time or move to a warmer environment

Can cold temperature cause incomplete cure: Yes

How do you get a clean edge on painted surfaces: Apply automotive masking tape before application

When should masking tape be removed: Immediately after tooling, before the sealant skins

Should you apply over degraded existing sealant: No, remove all old sealant first

Should you bring the tube to room temperature in cold weather: Yes

Why warm the tube before cold-weather use: Cold silicone is stiffer and harder to extrude evenly

Does applying more sealant improve the seal: No, excess does not improve performance

How is cured sealant removed: By mechanical cutting or scraping

How is uncured sealant removed: With a dry cloth or mineral spirits before skinning

Is ventilation required during application: Yes, work in a well-ventilated area

Should you avoid skin contact with uncured sealant: Yes

How do you remove uncured sealant from skin: Wipe promptly with a dry cloth before it skins

Should eye protection be considered during use: Yes, keep sealant away from eyes

What should you do if sealant contacts eyes: Rinse thoroughly with water

Where can the full Safety Data Sheet be found: Available from Selleys

Is this a consumer-grade product: Yes

Label facts summary

Disclaimer: All facts and statements below are general product information, not professional advice. Consult relevant experts for specific guidance.

Verified label facts

Product name: Selleys Auto Fix Auto Sealant
Manufacturer: Selleys, a brand under DuluxGroup Pty Ltd
Volume: 100 mL tube
Cure system: 100% neutral cure silicone
Acetic acid release: None — neutral cure chemistry does not release acetic acid during curing
Skin time: 5 minutes (at approximately 23°C and 50% relative humidity)
Dry to touch: 30 minutes (at approximately 23°C and 50% relative humidity)
Full cure time: 24 hours (at approximately 23°C and 50% relative humidity)
Cure condition notes: Cooler temperatures or lower humidity slow cure; warmer or more humid conditions accelerate cure
Service temperature range: -40°C to 180°C
Temperature range test standard: ASTM C1246:2017
Cured finish: Translucent
Application format: Hand-squeeze tube; no caulking gun required
Compatible surfaces: Glass, painted surfaces, fibreglass, most plastics, trim, most rubbers
Incompatible surfaces: Natural rubber, NBR (Nitrile Butadiene Rubber), Chloroprene/Neoprene
Nozzle cut angle: 45°
Tooling window: 5 minutes from time of application
Recommended tooling method: Gloved finger (latex or nitrile); lightly moistened with water or soap-water solution
Minimum undisturbed cure period: 24 hours; keep sealed area free from water, stress, and mechanical load
Storage requirements: Cool, dry location away from direct sunlight and heat sources; tube must be sealed between uses
Shelf life: Check expiry date on packaging before use; out-of-date product may produce incomplete cure, reduced adhesion, or abnormal skinning
Uncured sealant removal: Dry cloth or mineral spirits before skinning
Cured sealant removal: Mechanical cutting or scraping
Safety — ventilation: Use in a well-ventilated area
Safety — skin contact: Avoid prolonged contact with uncured sealant; wipe promptly with dry cloth before skinning
Safety — eye contact: Keep away from eyes; if contact occurs, rinse thoroughly with water
Safety Data Sheet: Available from Selleys
Product classification: Consumer-grade product
Technical reference: Selleys Auto Fix Auto Sealant Technical Data Sheet, DuluxGroup Pty Ltd, Version 1.0, Updated 10/12/2024

General product claims

Delivers waterproof, high-strength bonds across mixed automotive materials
Purpose-built for automotive and caravan applications; not a general-purpose silicone
Neutral cure chemistry is safe against metal trim, painted surfaces, and sensitive substrates without chemical attack
Resistant to vibration due to the flexible, elastomeric properties of cured silicone
UV resistant — suitable for externally visible or exposed applications
Weather resistant — withstands rain, humidity, and temperature cycling
Salt spray resistant — relevant for coastal driving and road salt environments
Detergent resistant — regular vehicle washing will not compromise the cured sealant
Translucent finish blends with most surface colours for a clean, professional result
100 mL format sized for targeted automotive work with reduced waste compared to larger cartridge formats
A smoothed bead achieves better surface contact, cleaner aesthetics, and reduced dirt trapping
Silicone's elastomeric properties accommodate joint movement without tearing
Applying over degraded existing sealant is a common cause of continued leaks
Excess sealant does not improve seal performance

Selleys Auto Fix Auto Sealant Translucent 100mL 08 product guide