Orange stuff in the cylinder

[Aasland]

So I pulled the head on my 95k 2006 FJR and see this:

Kinda neat that I can still see the cross-hatching. But that orange stain is wierd. No texture, nothing on the head, leakdown test is near-perfect, engine ran great.

I had an idea it might be water from a bad head gasket, but unfortunately I didn't get to examine the gasket before I tossed it.

Any ideas what it might be?

 

[2fjr]

Looks like rust in the fuzzy photo. Why did you pull the head ?

 

[supertankerm60a3]

I'll second the 'rust' idea.

 

[art miller]

Just a guess, has the bike been sitting for a long time? With the ethanol shit in the gas you will get moisture in the tank. If you use Sea Foam or other treatment it will absorb the water but it may convert to rust if the bike was shut down with un-burned fuel in the cylinders. What material is the cylinder walls, steel or ceramic?

 

[Aasland]

Looks like rust in the fuzzy photo. Why did you pull the head ?

I lost 2nd gear a while back and decided to fix it by swapping engines; I wasn't able to get the donor engine's exhaust valves to seal tightly so I swapped heads. Details here.

 

[Aasland]

Just a guess, has the bike been sitting for a long time? With the ethanol shit in the gas you will get moisture in the tank. If you use Sea Foam or other treatment it will absorb the water but it may convert to rust if the bike was shut down with un-burned fuel in the cylinders. What material is the cylinder walls, steel or ceramic?

I put the bike away for the winter in November, with non-oxy fuel and StarTron (which disperses the water so it gets burned; just like Seafoam).

We do have very poor gas up here in MN; 90% of the time my only choice is ethanol. But I make a point of always putting non-oxy in it when storing it for longer periods of time.

I agree it probably is rust; the question is how that moisture got in there.

 

[ionbeam]

My engine sat for about 6 weeks before it was opened up, by that time all my cylinders had the mystery orange fuzz too.

Hmm, aluminum engine and specially coated cylinder sleeves, what is there to rust orange? Aluminum rusts (oxidizes) white. When I wrote to the Forum about my orange fur lined engine the best guess was that it was fuel related. Moisture gets in through open valves. In the case of my engine 12 valves were open all at once. Ouch.

 

[RossKean]

Probably is rust but not from the cylinder wall. As the engine breaks in, a very small amount of material from the rings will deposit in the cross-hatching of the cylinder. This material will be very fine and will oxidize quickly. Shouldn't cause any damage as it will be very fine. I don't think I would worry about it too much. Wipe it away, button it up and forget it.

 

[lnewlf]

curious as to why there seems to be a lot of carbon on the piston crown...maybe this engine didn't see redline much?

 

[Fred W]

My engine sat for about 6 weeks before it was opened up, by that time all my cylinders had the mystery orange fuzz too.
Hmm, aluminum engine and specially coated cylinder sleeves, what is there to rust orange? Aluminum rusts (oxidizes) white. When I wrote to the Forum about my orange fur lined engine the best guess was that it was fuel related. Moisture gets in through open valves. In the case of my engine 12 valves were open all at once. Ouch.

Good question. The special coating is has always been touted to be "ceramic composite." Is it possible that there is some iron in the composite? The rust seems localized to just the upper edge near the head gasket. It could have been weeping coolant or maybe just was exposed when the head was removed?

curious as to why there seems to be a lot of carbon on the piston crown...maybe this engine didn't see redline much?

Maybe it's the 95k miles? How much carbon buildup is normal even on engines that do see redline occasionally?

 

[Fullchat]

How about condensation over the winter in the bores causing rusting?

 

[ionbeam]

How about condensation over the winter in the bores causing rusting?

There isn't much in an aluminum engine with aluminum cylinder heads and ceramic coated cylinder bores to rust. The bottom of my aluminum cylinder head and the domes of my pistons had orange fur. I also had a fair amount of carbon under the orange fur on my piston domes and I didn't/don't baby the engine. In fact I had been running my FJR at New England Dragway that summer.

 

[RossKean]

As mentioned above, there is likely a very small amount of iron from the rings embedded in the cross-hatch/ceramic coating on the cylinder wall. While this would be essentially invisible in the metallic state, a few milligrams would be enough to yield a pretty good fuzz of ferric oxide upon exposure to damp air. It would be easy enough to verify.

 

[Aasland]

Probably is rust but not from the cylinder wall. As the engine breaks in, a very small amount of material from the rings will deposit in the cross-hatching of the cylinder. This material will be very fine and will oxidize quickly. Shouldn't cause any damage as it will be very fine. I don't think I would worry about it too much. Wipe it away, button it up and forget it.

I think this might be the best explanation ... but .. then why is localized, appearing to have dripped down from the top, and not evenly spread across all the surfaces?

How about condensation over the winter in the bores causing rusting?

That's a good thought, but I'm going to rule this out. It doesn't get very humid here in the winter; in fact this has been a bitter cold winter and my [partially below-ground] garage has been at about freezing since December. The outdoor temps have been below freezing and that means moisture in the air will form ice crystals and drop out pretty quick.

 

[Aasland]

The engine was not exposed for long before I took that photo.

While we're on the topic of carbon deposits, there's the head after a first-pass of gum cutter:

The first pass removed the surface stuff; what you see above are the thicker deposits which I had to manually remove. They were particularly heavy in the squish zones.

And yes .. I did on occasion redline, if only because I had to go from 1st to 3rd so I'd wring it out in 1st.

For reference, here is the "new" (24k) head I didn't use ... before any attempts at cleanup:

Not much for deposits, but an interesting tan color. This engine was from DFW, TX ... averaging 3k/year it probably sat for long periods or was ridden short distances every day.

 

[mcatrophy]

...But that orange stain is wierd....

Any ideas what it might be?

We used to assume this sort of deposit was ground-up tiger hair.
Comes from using Esso (Exxon) fuel.

 

[supertankerm60a3]

Rust came fron the piston rings, those are still iron or steel. Water, or got to sit at the top area for awhile and got wiped as the piston moved downward.

 

[RadioHowie]

How long between the time the head bolts were loosened and the "rust" was observed?

Maybe it's just coolant stain?

 

[Aasland]

How long between the time the head bolts were loosened and the "rust" was observed?
Maybe it's just coolant stain?

I think a day. Or immediately. I looked at the cylinders immediately but don't recall if I saw the orange.

Damnit that was just last week. I should be able to clearly remember this fact. I do know that I wasn't looking for stains etc when I pulled the head,