Effects of ash on automotive paint/trim in Pacific Northwest

[OMGClayAiken]

So, I'm up here in Oregon with ash all over everything and its supposed to rain on Tuesday I believe. I've read some articles online regarding the effects of ash on cars and seems to be consensus that as long as it's dry there is no risk (unless you brush it off and scratch the car). However, some articles suggest that once it rains or otherwise gets wet, the chemical composition of the ash mixed with water produces something similar to drain cleaner which can obviously be damaging to automotive surfaces. However I have also been told that it takes boiling water mixed with the ash to turn it into lye and unless you have boiling (or very hot) water in the mix there is no risk to cars getting wet with ash on them. Any chemists on here able to weigh in on this?

[DUBL0WS6]

I think the ash gets acidic when it gets wet. If it rains hard enough it will probably just wash off. If it's just a fine mist that might let it dwell on the paint. Hopefully you're out of the range of the fire.

[Mr_Anderson]

I'm also in Oregon, in the Santiam Valley. I'm curious about this as well. I'd also like to hear any suggestions for washing ash-covered vehicles that are in addition-to, or instead-of, normal washing techniques.

[98CayenneTA]

I have had my Trans Am covered in ash for a whole weekend with rain mixed in from a massive skid pallet bon fire with zero effects.

[DMiglio]

I have had my Trans Am covered in ash for a whole weekend with rain mixed in from a massive skid pallet bon fire with zero effects.

This sounds like a heck of a party!

[98CayenneTA]

This sounds like a heck of a party!

It is for sure, it's a event called Power Cruise at Brainerd International Raceway in Minnesota.
First picture, we light all those off at once.
Second picture, the result lol.
Video at bottom is me in my Trans Am racing my buddy.

[The Guz]

Wash like normal. Here in the south bay area of California we are getting ash from the fires. Rinse every thing off and followed with normal washing methods. The paint didn't explode so I would say it was a success. Follow up with your spray protection of choice. Expect to be washing more often.

The ash subsided a bit and rinselessed washed 3 days later with no issues. Just a heavier pre-soak.

[UncleDavy]

It depends on what is burning and what is in the air. If it is a forest fire, I don’t think that any of the burned organic matter would cause any harm to the paint. Harmful ash usually comes from acidic material in the air like a volcanic eruption or coal exhaust. Anybody who has worked at a coal burning power plant can tell you what coal ash can do to a car’s paint. It makes it disappear. Burning coal releases sulphur dioxide. When mixed with rain you get sulphuric acid otherwise known as acid rain.
I would equate your situation to fireplace ash and when mixed with water it creates a base. It is not as harsh as household lye (pH value of 14), but it can be alkaline (pH value of 12). Just as a comparison, undiluted Megs D101 has a pH value of 13. My advice would be hose it off as soon as you can.

[Baumeister]

I'm certainly no expert but I'm in Northern California. For our recently acquired VW convertible I've been delayed prepping the canvas to apply RaggTop. First it was the heatwave and now it's the ash keeping me from a perfect prep. This week I did start using the leaf blower to get the ash off the top before hitting it with the water hose, wound up just blowing the ash off the whole car to minimize issues.
We had a short window when the AQI was lower than 100 so I went ahead and cleaned one last time, let it dry overnight and sprayed the RaggTop. There was still streaky residue from whatever protection was on it previously that won't come off, I just had to stop cutting bait and fish to get some protection on this 5 year old car that started life in San Diego and Las Vegas.

We recently moved and I'm really missing having an enclosed garage to work in!

[Mr_Anderson]

I have had my Trans Am covered in ash for a whole weekend with rain mixed in from a massive skid pallet bon fire with zero effects.

Sweet Trans Am you have there. Also, I was going to guess Burning Man until I read your next post in this thread.