Can anyone recommend a solution to clean two stroke exhaust marks from the back of the hull? My old inboard is two cycle
Removing Two Stroke Exhaust Marks
- Thread starter Project_Mayhem
- Start date
That kind of stain possess a unique chemical challenge. If the stain is soot, then it is mostly carbon black and there are no chemical bonds to attack. So, you need to oxidize the stain. Make a balm out of an oxidizing agent... something like Oxy-clean or hydrogen peroxide... and slap that over the stain … and then let is sit… might work. That will oxidize the carbon to carbon dioxide and it will leave the pores of your gel coat. There will probably still be some discoloration but that will be handled with the next suggestion
If the stain is greasy and has some chemical structure left in molecular form, I’d recommend a balm of very strong detergent-solvent (like pine sol) … let is soak for a while…followed by a scrubbing with an oxalic acid cleaner (like Bar Keeper’s Friend). If that does not work, try a mineral spirits cleaner (like goof off).
If the stain is greasy and has some chemical structure left in molecular form, I’d recommend a balm of very strong detergent-solvent (like pine sol) … let is soak for a while…followed by a scrubbing with an oxalic acid cleaner (like Bar Keeper’s Friend). If that does not work, try a mineral spirits cleaner (like goof off).
I've been using Gel Gloss for years now. Does a good job with soot stains from the exhaust. At Home Depot.
Original Gel Gloss RV One Step Polish and Protector 16 oz. Liquid GG16 - The Home Depot
Original Gel Gloss RV One Step Polish and Protector - The complete RV detail product originally designed for use on fiberglass, acrylic, tile and cultured marble. One step application polishes, protects,
www.homedepot.com
The finest wet sanding paper I use when chasing spider cracking is #3000 grit. Meguiar's #44 would be the equivalent of about #one zillion grit. The description says it only goes after oxidized gel coat so that gives you an idea of how mild it is.
If you ditz around with gel coat repairs on a hot, sunny day in a lazy anchorage as I frequently do chasing spider cracks, you'll have discovered this stuff :
More aggressive than #44 in that it will remove #3000 grit scratches quickly but also produces a mirror finish. Weird combination of deteriorating grits but there's no denying the final mirror polish. Forms a hydrophobic, greasy mess when working so can't be use with a mechanical polisher. Somehow it dries to a dusty polish and wipes right off.
This is the coarsest liquid application I've come across and is not coarse enough to be considered a liquid wet sanding.
I know this is an old thread but I finally got all of my must do boat projects done. I was able to reduce the exhaust stains by about 70% with acetone today. Unfortunately I ran out so hopefully the rest will come off when I get some more.
As for SOME of the Meguire's products, they might contain silicone. The wax/cleaner I had gave chaulky gelccoat a great shine in less than a minute by hand. Too good to be true. Luckily they list ingredients on their website.
As for SOME of the Meguire's products, they might contain silicone. The wax/cleaner I had gave chaulky gelccoat a great shine in less than a minute by hand. Too good to be true. Luckily they list ingredients on their website.
Ah yes, silicone. Another old wive's tale perpetuated by sailboat web sites.
Yes, silicone will cause adhesion problems with new gel coat, paints, etc. However, a quick wipe with #600 wet/dry emery paper ensures that any contaminated gel coat is quickly removed. Even if you plan to paint your exterior, silicone would be the last thing on my mind as you will be sanding the gel coat before painting.
How long will this stuff hold up?
Meguiar's® Marine/RV One Step Cleaner Wax, M5001, 1 Gallon, Liquid | Meguiar's
Never tried it before so can't say. This is the latest stuff I've tried. Seems to last for a few extra months and doesn't turn yellow and require stripping before waxing again.
That's the one for me - at least until something else comes up on sale
. I've tried them all and each one seems to have a different appeal.
That's the one for me - at least until something else comes up on sale
. I've tried them all and each one seems to have a different appeal.