Exhaust valve white color..strange? Pictures included.

[berlyn]

Hello fellow Bitogers,

please check the attached picture.
The fact that the valve seems white makes me worry. Is this normal? Why isn't it covered with carbon like the surrounding surfaces?
If you also zoom in, you will see that there is something like surface roughness - small white spherical formations. What is this?

Thank you for your feedback,

kind regards,

Berlyn

 

[berlyn]

... and a closer view.

 

[RooflessVW]

Lean running?

 

[Rand]

Do you use any fuel additives? Some can cause that.

also what engine/vehicle

 

[LvR]

Looks confined to guide area as source ................. what oil and any additives there?

Is it just that one particular stem or all of them?

 

[CT8]

How do the other exhaust valves look and why did you take the manifold off? How does the engine run ,the valve lash if adjustable and the compression. There could be an intake vacuum leak does the engine smoke when you start it up after sitting????

 

[PimTac]

What vehicle is this? Make, model and year.

My first guess is that you are running lean.

How about your coolant level? Have you had to add any?

 

[Kestas]

I had white deposits on the exhaust valves of my 1971 Oldsmobile. When i analyzed it, it was basically a lead compound.

 

[Linctex]

This is 100% normal for modern EFI engines.

Go to a wrecking yard and look in the ex ports of "good running" engines - the valves are always white.

 

[c502cid]

Originally Posted by Linctex
This is 100% normal for modern EFI engines.

Go to a wrecking yard and look in the ex ports of "good running" engines - the valves are always white.


^^^^this^^^^

 

[02SE]

Pretty much normal these days. What bike is it?

 

[ka9mnx]

Originally Posted by Linctex
This is 100% normal for modern EFI engines.

Go to a wrecking yard and look in the ex ports of "good running" engines - the valves are always white.

Yep.

 

[46Harry]

From what I see in the pictures, you have a bit of a build up of combustion by products from things like additives in the oil and fuel burning off, there is nothing to worry about.

 

[racin4ds]

White, hard deposit like that is usually indicative or oil burning. Very common to see in modern engines with some mileage.

 

[berlyn]

Hello all,

firstly thank you all for your questions and feedback, I suppose it leads me to a conclusion, below further feedback, teamwork in Bitog is great

@rooflessVW
Lean running?
Perhaps it could be, as the EFI in programmed by the factory to be lean in low rpm, the engine has not seen above average rpm except from a very few times during the last years.
@Rand
Yes, I used RL SI-1 for one complete tank, once and that was it. Now, as the bike sits, there is fuel stabilizer in the tank - I drove around 20km on fuel stabilizer before dismantling the manifold. Could this be the reason?
The engine belongs to a bike (Honda Varadero 1000cc, year 2005, V2 90deg, 95HP, redline 8750rpm).

LvR
Oil is Amsoil MCV or Mobil Vtwin, no additives in oil, all stems look the same.

CT8
How do the other exhaust valves look and why did you take the manifold off? How does the engine run ,the valve lash if adjustable and the compression. There could be an intake vacuum leak does the engine smoke when you start it up after sitting????

Hi CT8, all valves look the same. I took off the manifold in order to change the graphite rings in the connections of the exhaust pipes. I should clean off any deposit from the old rings, by sandpaper, this job could not be done unfortunately with the pipes on the heads. Engine runs well, lash is within specs, I have not measured the compression, intake vacuum leak not possible, I disassembled the air filter box during maintenance, no trace of air entering the system except from the correct route. Engine does not smoke. What else could be a reason?

PimTac
What vehicle is this? Make, model and year.

The engine belongs to a bike (Honda Varadero 1000cc, year 2005, V2 90deg, 95HP, redline 8750rpm, ~45kmiles).

My first guess is that you are running lean.
How about your coolant level? Have you had to add any?

Well yes and this makes me worry now that I hear it. I added ~500cc every 2000km, engine was smelling like boiling antifreeze slightly when it ran, I replaced all hose clamps, now no smell whatsoever. I hope this is the reason of adding coolant. If not, then I am in trouble.

Kestas
I had white deposits on the exhaust valves of my 1971 Oldsmobile. When I analyzed it, it was basically a lead compound.

Hello Kestas, the engine runs on unleaded - is there another source of lead that I should check that could result in the above seen pictures in your opinion?


Linctex
This is 100% normal for modern EFI engines.

Go to a wrecking yard and look in the ex ports of "good running" engines - the valves are always white.
Hi Linctex
I hope you mean actually good running and not adding a sense of humor

you see I don't understand completely the quotes

you mean it is common?

02SE
Pretty much normal these days. What bike is it?

Hi 02SE, you got it right, it is a bike! Honda Varadero 1000cc, year 2005, V2 90deg, 95HP, redline 8750rpm.

46Harry
&
racin4ds


From what I see in the pictures, you have a bit of a build up of combustion by products from things like additives in the oil and fuel burning off, there is nothing to worry about.

thank you, I also tried not the best quality gas in remote areas I visited last autumn, had no alternative, maybe this could be a reason. Mileage is 70.000km, or roughly 45kmiles, oil consumption is ~100ml/1000km.

I also forgot to mention, that white deposits are also located on the low side of the inside cross section of the pipe and seem like teardrops (imagine the pipe is ‘elbow like' at this point so lower gas velocity due to the vertex--> deposits). I used sandpaper to remove them, they converted to powder immediately without resistance.