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Grunt boat cleaner is specifically formulated to remove those “hard to shift” stains from fibreglass boats that we all know so well, those ugly yellow/brown waterline stains, rust staining from metal fittings, exhaust staining, bird lime and many other deeply ingrained stains typically found on our boats.

Also Grunt now needs far less time to take effect and you can wash it off after just a few mins!

How to use Grunt : https://www.youtube.com/watch?v=sAbvpzTXBMQ




Grunt boat cleaner is specifically designed to make cleaning those nasty stains from your boat an easy task, so easy in fact you wont believe it!

Grunt boat cleaner penetrates into the gelcoat and using a chemical reaction gently neutralises and absorbs the staining without affecting the gelcoat in any way. The stain can then be simply washed off with a sponge and water.

To use Grunt Boat Cleaner simply apply to the stained area with a paint brush –  the product now works in just 3-4 minutes–  Grunt really does all the hard work, magically neutralising and absorbing the stain ready to be rinsed off… it really is that simple!!!

It is non-hazardous for transport and is even more environmentally responsible and safer than most products on the market.

Whilst primarily designed for use on fibreglass boats Grunt boat cleaner is also works brilliantly on most two part marine paint systems and yacht enamels typically used on steel or timber boats.

Application Manual

To achieve the best results please follow the procedure outlined.
Shake well before use

1) Pour some Grunt boat cleaner into a clean bucket or other suitable container; make sure that the bucket is dry inside as any water present will dilute the cleaner making it less effective.
Grunt boat cleaner is formulated in a gel consistency to enable it to be used on vertical or overhead surfaces.

2) Apply Grunt boat cleaner to the stained areas using a small paint brush. For larger areas or for heavily stained hulls it may be necessary to coat the entire hull, this can be easily achieved using a larger brush.
Treating just a small area may leave you with a “clean spot” showing up the dirt and staining on the rest of your boat necessitating an overall treatment. To avoid leaving “clean spots”, the entire area should be treated with Grunt boat cleaner.

3) Always ensure the area to be cleaned is free from all old wax or polish as this may affect the working of Grunt as the wax will act as a barrier not allowing Grunt to reach the staining in the surface below and stopping it working properly. A wash with any standard boat wash will remove any wax or polish remaining on the surface.

4) Leave Grunt boat cleaner on the surface for approx 3-4 minutes, longer in colder weather or heavier staining, and then rinse off with a sponge and clean water.
Remember Grunt works purely by a chemical reaction therefore it is vitally important to allow Grunt “time” to gently neutralise the stains and absorb them. Grunt is designed to do the work without you.
Grunt boat cleaner should not be allowed to dry out on the surface if it is to remain active. If this does happen on a very hot day apply another light application.

5) For stubborn stains re-apply Grunt boat cleaner to that area and leave for longer. Thoroughly rinse the entire surface with a sponge and fresh water. You should now have a beautifully clean boat. To maintain your boat in this condition you can apply a high quality marine carnauba wax which seals the surface helping prevent further staining.

Although Grunt boat cleaner is primarily designed for use on fibreglass it is compatible with most two-part paint systems currently used on many timber and steel craft. If you are unsure about the type of surface you are treating always try on an inconspicuous area first.

Always, always wear your PPE (Personal Protection Equipment, ie: goggles, gloves etc) when handling any chemical, its good practice!

Additional information

Weight N/A

500 ml, 1 Litre