The bilge on the Currawong is a small, deep "V" directly under the engine and gearbox. Over the years, the bilge on Kinora has built up a fair amount of sticky, black sludge on the walls of the bilge. Parts break off and then foul the check valve on the bilge pump so I need to do a thorough clean. The advice received so far is to soften the gunk, scrape off as much as possible, wash with a degreaser. Difficult and laborious work in a confined space.

What have others done to thoroughly clean contaminated bilges?

Cheers,
Kinora

I have found that the op-shops sell what they call "dog towels". Perfectly good, washed towels that can't or won't be sold for human use. I like to get four or five, round the bill up to the nearest 10 bucks and use then throw away. Very good for getting dirty bilgewater up including the particles that contaminate it.

Kinora said..
Thanks, Phil and JonE. I was hoping there was an easy way but in the end I've used De-solv-it, rags, paper towels and Starbrite degreaser with warm water wash. Access is really bad, I've had to remove the cooling water inlet hoses and filter to get access to the bilge. The best scrubbing tool so far has been a long handled toilet brush, the kind with a rounded, cylindrical head. Today, I'll invest in a mid-range wet/dry vac to suck wash and rinse water out. Dick Smith sell a steam cleaner with a long wand. It also has a hot water jet (but you have to change attachments). I think the combination of a steam jet, hot water rinse jet and a wet vac would make the job easier.

I'm thinking of building a fibreglass tray lined with oil absorbant pads to sit under the engine and gearbox but above the level of the Water Witch to keep oil and fuel leaks or spills separate from the bilge water. Anyone tried this?

Cheers,
Kinora

I have a stainless steel tray under my engine.

Thumbs up to a shop-vac, I’ve got a n ozito 18v one and it’s fantastic for this job, the 20 ltr Bunnings buckets with lid are ideal for emptying the shop vac into as well.
I taped a smaller diameter hose to the main one and a piece of broom handle taped along side it to poke it right down into hard to reach places

saltiest1 said..
Brake cleaner is your friend. We constantly use it on the windfarms for old and new grease removal and is very efficient.

I hope the wind turbines are epoxy resin and not cored. Both types of brake cleaner can damage cured polyester resin and, more seriously, core foam. How badly depends on which brake cleaner and which foam.

(from SDS data):
1. Non-chlorinated brake cleaner is mostly acetone (typically 70–90% acetone), with heptane, naphtha, and sometimes toluene, xylene or methanol, plus a CO₂ propellant.

2. Chlorinated brake cleaner uses perchloroethylene (tetrachloroethylene) as the main ingredient, and older/aggressive formulations may contain methylene chloride (the active in most paint strippers).


On polyester resin (cured GRP/gelcoat): Prolonged contact or pooling is a a problem. Acetone softens and crazes gelcoat and the resin surface, and chlorinated types (perc, and especially methylene chloride) are aggressive to cured polyester.

The real risk is you have foam core (less likely in the bilge):

PVC foam (Divinycell, Airex, Klegecell): attacked by acetone and by chlorinated solvents — softening, swelling or dissolution.
SAN foam (Corecell): styrene-based, so susceptible to aromatic solvents and ketones.
Polyurethane foam: particularly vulnerable to chlorinated solvents.


The common way to wreck a cored panel isn't the resin skin failing — it's solvent wicking through a fastener hole, hairline crack or thin/repaired skin into the core, where it quietly eats the foam without you seeing it (I did it once on a Taipan Cat 20 yrs ago)

Don't use brake cleaner on or near composite structure, repairs, or any exposed core. For degreasing, isopropyl alcohol (IPA) is far safer and won't touch the foam.

EastCoastSail said..

saltiest1 said..
Brake cleaner is your friend. We constantly use it on the windfarms for old and new grease removal and is very efficient.

I hope the wind turbines are epoxy resin and not cored. Both types of brake cleaner can damage cured polyester resin and, more seriously, core foam. How badly depends on which brake cleaner and which foam.

(from SDS data):
1. Non-chlorinated brake cleaner is mostly acetone (typically 70–90% acetone), with heptane, naphtha, and sometimes toluene, xylene or methanol, plus a CO₂ propellant.

2. Chlorinated brake cleaner uses perchloroethylene (tetrachloroethylene) as the main ingredient, and older/aggressive formulations may contain methylene chloride (the active in most paint strippers).


On polyester resin (cured GRP/gelcoat): Prolonged contact or pooling is a a problem. Acetone softens and crazes gelcoat and the resin surface, and chlorinated types (perc, and especially methylene chloride) are aggressive to cured polyester.

The real risk is you have foam core (less likely in the bilge):

PVC foam (Divinycell, Airex, Klegecell): attacked by acetone and by chlorinated solvents — softening, swelling or dissolution.
SAN foam (Corecell): styrene-based, so susceptible to aromatic solvents and ketones.
Polyurethane foam: particularly vulnerable to chlorinated solvents.


The common way to wreck a cored panel isn't the resin skin failing — it's solvent wicking through a fastener hole, hairline crack or thin/repaired skin into the core, where it quietly eats the foam without you seeing it (I did it once on a Taipan Cat 20 yrs ago)

Don't use brake cleaner on or near composite structure, repairs, or any exposed core. For degreasing, isopropyl alcohol (IPA) is far safer and won't touch the foam.

I don’t think you need to worry about the surface we use it on and it’s not the blades. More the mechanical side of things and the nacelle area. Isopropyl has been banned in these areas due to introduction of a flammable liquid and some confined space issues so non flammable brake cleaner is used instead.