Corrosion on oil pan bolts

[blind*guardian]

Was under the car a few days ago and noticed that a few of the bolts that hold the plastic oil pan look to be covered with something brown or corroded. Did anyone see something similar before? Galvanic corrosion maybe?

Sponsored

 

[cmxPPL219]

That's really interesting. It could be. Because the bolt is strangely corroded, like it was at the bottom of the ocean, while the surrounding area looks new.
And I see you're in CA? So no snow and salt to deal with.

How are the other other bolts? Exhibiting the same condition?
It's just tricky as to whether it is, because you have the head of the bolt in contact with the composite oil pan, but I believe the holes of the oil pan are "sleeved" with some sort of metal sleeve (I think non-threaded), so that it's not just a bolt through the composite material only.

It's also definitely not some oil/fluid leak, because of the crusty-looking Popeyes fried chicken skin that seems to be growing there...

 

[blind*guardian]

Yeah it’s a bit odd for sure... about half the bolts are clean and half look like this. There’s also a bit of this crusty brown stuff visible on the picture between the pan and the aluminum block. Maybe it’s dried oil, but normally that would just be wet and oily I’d think.

 

[cmxPPL219]

Interesting. It's not dried oil, this is for sure.
Even if something got mixed into the oil, (like coolant) it wouldn't crust-over like that. Hmm...

 

[Whitest Russian]

I'm guessing your 2019 is till under warranty so you you could always go to a dealership and have them poke around to make sure nothing weird is going on.

Definitely weird how the rust looks pasty. Maybe Ford got a bad batch of bolts that made their way onto your car?

 

[blind*guardian]

Yeah next time I’m over at the dealer will ask. I figure the dealer would probably just replace these, but will see, maybe they’ll know more.

The other thing it could be is perhaps dried coolant? The coolant is orange now (I think). So maybe there’s a coolant passage that was leaking a bit.

 

[Whitest Russian]

Yeah next time I’m over at the dealer will ask. I figure the dealer would probably just replace these, but will see, maybe they’ll know more.

The other thing it could be is perhaps dried coolant? The coolant is orange now (I think). So maybe there’s a coolant passage that was leaking a bit.

You can always mark your coolant level with some masking tape or a marker and see if it goes down. Engine coolant is supposed to inhibit corrosion though.

 

[Mike Pfeifer]

It’s hard to really tell from the picture, but it doesn’t look like rust to me. It looks like some substance is coated on the bolt and dried up. I would want to know if it can be dissolved by water or something, or is it attacking the metal of the bolt? Finding that out may tell you what direction to look next. My only concern is the substance being all the way through the oil pan bolt sleeve. Does Ford use a sealant on the oil pan gasket? My money is on foreign substance dried up, not rust.

 

[Cobra Jet]

In your picture, to the RIGHT of the bolt, the same crusty orange substance is seen sandwiched between the black and bare metals. It looks to me like something leaked or is seeping down and is finding the path of least resistance.

See if you can get a powerful light under there more or even a black/blue light which reveals any leaks.

Whatever that is, it could be reacting in a negative manner with the metal composition of the bolt.

Hard to tell the location from you pic being it’s zoomed in on only 1 bolt, but is it near the battery, battery cables, or any other source of possible leaks?

 

[blind*guardian]

In your picture, to the RIGHT of the bolt, the same crusty orange substance is seen sandwiched between the black and bare metals. It looks to me like something leaked or is seeping down and is finding the path of least resistance.

See if you can get a powerful light under there more or even a black/blue light which reveals any leaks.

Whatever that is, it could be reacting in a negative manner with the metal composition of the bolt.

Hard to tell the location from you pic being it’s zoomed in on only 1 bolt, but is it near the battery, battery cables, or any other source of possible leaks?

There isn’t any other evidence of leaks from what I could tell. It’s just around the few bolts. I’m leaning towards this being a coolant leak, but obviously very minor. I’ll monitor it over time to see if it gets worse. Also, there aren’t any cables or batteries there, just the oil pan and the engine block.

Was going to do my own oil change, but maybe will take to a dealer in a few months instead for them to take a look at it.

 

[Rapid Red]

"Galvanic corrosion maybe"
Plastic & steel ?

If i saw this, sure would not waste my time running to the dealer. Clean the area, change the oil, and check next maintenance cycle.
Pan will not fall off..

agree with Mike Pfeifer... sealant

Bolt is colored, but not crusty

 

[Elp_jc]

Since it's also between the pan and block, as noted by Cobra Jet, it's definitely coolant IMO. But the better question is where did it come from. At any rate, I'd just remove the bolt, clean everything really well all around, install a new bolt, and see what happens. Hopefully not a leak, but coolant that somehow ended up there during production. Good luck.

Sponsored