How to kill mold on billge/engine surfaces

[ratdude747]

Went to change my fuel filter today and discovered fluffy white mold all over the starboard side of the bilge around the gas tank and on the thermostat housing:



For this situation, what's the best solution? Or will it resolve itself with time and use once the season starts?

 

[Chris1956]

Bleach kills mold mildew and lots of other stuff. If using on fiberglass, you can use it full strength. If on vinyl or cloth, dilute it maybe 7::1 and see how it performs. Also, don't leave the solution on the vinyl or cloth for too long.

There are other mold killing marine products, however, if the surface is bare fiberglass, wood, plastic etc. bleach works really well.

 

[ratdude747]

Bleach kills mold mildew and lots of other stuff. If using on fiberglass, you can use it full strength. If on vinyl or cloth, dilute it maybe 7::1 and see how it performs. Also, don't leave the solution on the vinyl or cloth for too long.

There are other mold killing marine products, however, if the surface is bare fiberglass, wood, plastic etc. bleach works really well.

It's on braided fuel hose surfaces (filler and vent hoses), the painted fiberglass bilge wall, and a gasket joint between a painted cast iron thermostat housing and a cast aluminum intake manifold.
Per further review some of this was "dormant" in the past... seems the current temperatures and abundance of condensation has woken it up?

Bleach is what my mom used when we de-molded some of my dad's toys we recovered from grandpa's basement when I was a kid. But, I wanted to make sure that such is the right call here.

 

[Scott Danforth]

Starbright mildew and stain remover

Or

CLR mold and mildew remover

 

[airshot]

Look for cleaning vinegar, 6% acid, has worked d well for me cleaning/ killing mold. Has not harmed anything so far and actually does a good job of cleaning. I add it into a spray bottle uncut and spray everything. A day or two later rinse it away.

 

[Pmt133]

I've worked some miracles with spray 9. The starbrite stuff is good too. Vinegar works, simple green works... like pretty much any mild cleaner works honestly.

 

[crazy charlie]

Bleach in a spray bottle will work the best.Regular old bleach, nothing fancy like the "easy pour" or "no drip or easy pour" , just regular bleach .Leave on for a good minute or two tops and rinse with fresh water. BTW dont use the dollar store bleach unless they have the one in the smaller green bottle.If you use vinegar DONT use cleaning vinegar as it is diluted and weak. Vinegar will have to stay on much longer than the bleach and may require a second treatment or a light brushing of the mold before a water rinse. Charlie

 

[tphoyt]

I’m a bleach guy myself but be sure to give everything a good rinse. It can be corrosive if not diluted.

 

[jlh3rd]

and don't buy the generic or discount bleach. Most if not all of those do not have the concentration % that name brands do.

 

[tphoyt]

So true. Some say disinfecting bleach and are not the same. I’m a fan of the Clorox outdoor as it has a surfactant and sticks to every much longer.

 

[Pmt133]

I've taken some out of the eductors at work for... uh... "work related" cleanup. (If it happens in the parking lot, it's work related.) keep in mind that would be hypochlorous and at a way higher concentration that what you could get off the shelf.

I've also used pool shock from my family's shop... that's like 15-16% hypochlorite per sds. You have to dilute that. Again... pretty much anything works.

 

[dingbat]

I've also used pool shock from my family's shop... that's like 15-16% hypochlorite per sds.

That's pretty low....assuming sodium hypoclorite
I use calcium hypocrite at 73% for shock.

The Starbrite stuff works wonders cleaning in the bilge.

 

[Pmt133]

That's pretty low....assuming sodium hypoclorite
I use calcium hypocrite at 73% for shock.

The Starbrite stuff works wonders cleaning in the bilge.

Liquid sodium hypo. The granular (and cal hypo) for that matter can take you much higher but you really don't need much. For liquid outside of some special lab solutions you probably won't find much higher than 15% anyway. Most industrial grades are in that range. The generators on saltwater pools top out at 1% or so...

The starbrite does work great.