I posted this on another forum and was wondering what you fellas thought or if you could help with what you think this stuff is while I clean it and trouble shoot the next few days. Any help or suggestions would be appreciated.

Here's the link and the write up below is the same:

Weird film/spray on my valve covers. - Ford Truck Fanatics

I'm not a mechanical guru like most of you fellas on this forum, so don't beat me up too bad on this question, but I'd thought I'd run it by you guys since I don't like running to a local mechanic for every little thing. Besides, you guys have been far more knowledgeable than any local mechanic on issues relating to my dent since I've been on here and I've been learning a lot.

My rig, since it's rebuild only has 11k miles on it, with about 5k put on since this past Spring. I took it out yesterday and noticed some white spray on both of the valve covers and a little under the air cleaner and wondered if you guys had any thoughts. I've driven this thing through the rain and through puddles and such an had never had this sort of stuff show up where it is now or anywhere else in the engine bay for that matter; just this last 60 mile or so trip. This is the first time I've seen this stuff in my engine bay. When I touch it or try to scrape it with my finger nails, it almost feels like it's eating away at the aluminum covers and has to be scraped off and then repolished.

I don't smell gas when I rub my fingers on it, but that doesn't mean anything....could just be dry.

Could some fuel be spraying from my carb?

What should I check if anything? Thanks for any help.

 

hey Ive seen that happen to aluminum before just never so quick, Its some kind of oxidation process. I had the same problem with my aluminum parts and heres my theory, I used to live in massachusetts right by the ocean and I believe the salt around those parts, possibly where you live too contributes.

 

Corrosion is oxidation. To stop/prevent it you need to keep oxygen from getting to the aluminum.
Polish them to get rid of the oxidation, then either give them a good coat of wax (temporary) or spray them with clear gloss. This will stop the oxidation.

 

Did you drive through some place that sprayed de-icer on the roads?

 

I live in Western Maine so not too much sea salt our way.

The waxing is something I should have done and hadn't, but it's surprising that it happened only within the last few miles.....almost overnight.

It's possible. Someone else suggested this....I live in rural Maine where these guys lay down salt and liquid calcium like there's no tomorrow, however, nothing has been sprayed this year yet. The time I took it out and it just about corroded over night, there was a lot of rain and it was on many back roads, so could there have been residual from last winter?

 

It's oxidation that looks like it's from some sort of salt.

 

Looks like electralasis (?), a corrosion that affects aluminum. I used to have airboats and it was usually a minor problem, it sometimes after years developed into a major one. A few guys had a disconnect in there battery cable they could flip if the boat was going to be parked in the water for any length of time. There is a connection between the electrical current and the boat being in water that promotes electralasis or so they said.

 

Yeah, but can it happen literally overnight? When I say overnight, probably within just a few days and about 60 miles of driving. My rig has 11k miles on it and it's been fine, then from one day, almost to the next, it looks like this.

 

Did you recently clean the engine. Have seen some cleaners/degreasers do this to aluminum

 

Welcome to New England... Warm humid days and cool nights produce condensation.
It's happened to all my once nice looking carbs, ect... After sitting... It doesn't take long... All little shot of WD40 or other light oil, and they will clean right up.. Other than that, I gave up on it years ago, it will still operate fine with a little discoloration on there... The only real answer if your that concerned is to put it in a atmosphere controlled storage unit when your not driving it...

 

Not like you're talking about. The truck is garaged and I only take it out on occasion, so engine compartment is immaculate at all times. When I do clean it for shows, I usually just do a wipe down of the valve covers, alternators, and side walls, and brackets....otherwise, no chemicals in the engine. There's no grease or anything in there either....you can eat off this engine bay.

Yup....temp has certainly been off and on up here. It was mid 20's some mornings last week and yesterday was 66 for the high...nice.

Thanks...