Tips on cleaning oil from a boat hull

Marine paint manufacturers Interlux and Awlgrip have offered some tips on cleaning oil from boat hulls for those boat owners who may find their vessels fouled by oil from the Gulf of Mexico oil spill.

From the press release: In the wake of what could be the largest oil spill in US history, leading yacht paint manufacturers Interlux and Awlgrip offer boaters in the impacted areas the following tips to help clean contaminated boats.

The surface of an antifouling paint that has become contaminated with oil can become “blocked” i.e preventing the biocide from being released, which subsequently leads to premature fouling. It will also result in a contaminated layer that will make adhesion of new antifouling applications difficult.

Cleaning of contaminated antifouling surfaces:

For hard polishing and ablative antifouling paints that have been heavily contaminated the best method to use when treating the bottom is to use a paint-stripper such as Interstrip 299e to remove all the pollution and the paint, then scrub the substrate using Fiberglass Surface Prep YMA601 and a coarse Scotch-Brite pad. Rinse with fresh water. Repeat until the surface is clean (when the water cascades off of the surface with no beading or separating). Allow the surface to dry thoroughly prior to re-painting. The same process is recommended on metal boats however to avoid corrosion the metal substrate should be prepared by grinding or blasting after the cleaning process and prior to priming. To aid adhesion apply InterProtect 2000E primer per label instructions.

Sanding or sand blasting a surface that still has oil on it may drive the oil into the surface and cause a loss of adhesion of the subsequent coats.

If the coating of oil is light, powerwash and then use a household detergent with water to scrub off any pollution. Then scrub using Fiberglass Surface Prep YMA601 and a coarse Scotch-Brite pad and rinse thoroughly with fresh water. Let dry prior to re-painting. Polishing paints such as Micron Technology, may be re-launched without painting assuming the film thickness of remaining paint is adequate (2-3 mils dry after scrubbing) & the next application is scheduled within 5 months.


Cleaning of contaminated topcoat surfaces:

Contaminated topcoats should be cleaned as soon as practically possible to minimize the damaging effects of the crude. If the surface of a topcoat is contaminated with crude oil, staining and possible degradation of the topcoat may result from the acidic nature of the contaminant. The recommendations below apply to Awlgrip, Awlcraft 2000 and Interlux Perfection topcoats. If there is any doubt of the type of surface in question always test a small area first.

In the case of heavy contamination, the material may be a thick, sticky tar-like material due to its exposure to the elements. It is recommended that these surfaces first be cleared by wipe down with T0016, T0170 or Mineral Spirits followed by power washing, and then cleaned with Awlwash at a 4 oz/gallon level (or household liquid detergents such as Dawn). The detergent washing step of the cleaning process must be done in manageable areas. Each area should be then be thoroughly rinsed with plenty of clean water before moving on to the next. DO NOT allow detergent solutions to dry on the surface.

Hulls exhibiting ‘sheen’ contamination may be cleaned with the regular concentration levels of Awlwash, though they too may benefit from a prewash wipe down with T0016, T0170 or Mineral Spirits to loosen the film.

In both cases, it is recommended that the newly cleaned surface be protected from further contamination with application of Awlcare.


Contaminated waste water should be collected per local marina guidelines, local authority regulations and/or Clean Water Act requirements. Collecting the water and the emulsified crude will prevent spreading of contamination. Crude and solvent contaminated wipes must also be disposed of in a responsible manner.

For further assistance, call Interlux Technical Service, 1+800.468.7589 or Awlgrip Technical Service, 1.888.355.3090. For more information about Interlux products, visit For more information about Awlgrip products, visit

By Ocean Navigator