Is Stihl Ultra HP Oil no good?

[lone wolf]

Not sure a few milligrams of wood dust per gallon of 2Mix is gonna score aluminum...don't they use aluminum oxide to sand wood?

Well, I think a lot of it will over many hours.

 

[HansFranz]

Well, I think a lot of it will over many hours.

...especially if you take the air filter off every 10 minutes and beat the $h!t out of it on a rock,
or blow it out with 175psi air until 2" gravel will go through it without touching anything.

A lot of these guys seem to think they're running F1 cars.

 

[ZeroJunk]

I have a 500i that seized on the exhaust port side , using 45 to 1 fuel and have been for years in all my stihl saws ( MS660 MS088 MS036 ) with no problems the 500i is about 2 years old and has turned into my goto saw for its power to weight ratio. Was using with a 24 inch bar and it just stopped, no signs of a impending seize , thought it was fuel but still had 1/2 a tank , went to pull over and it was solid. I am replacing the barrel and piston but would love to know WHY it seized. If anyone has seen this happen before and worked out why I would love to know, Thanks...Allan.

I cleaned the cylinder up today on the one we had that was scored and rings stuck.
If you looked in the exhaust port it was scored on the left maybe 1/4 inch of the piston.
If you looked in the intake port it was scored on the left maybe 1/4 inch of the piston. Opposites.
Really easy clean up.
Certainly nothing like being straight gassed.
Dogged too hard with a dull chain ?
Like I said in an earlier post the diagnostic said the fuel dosage was where it was supposed to be.

I was struck by the lack of any carbon build up in the top of the cylinder. Like none.

 

[bwalker]

Not convinced that a few milligrams of wood dust ingested per gallon of 2Mix is gonna score aluminum.
Don't they use aluminum oxide to sand wood?

If it's sucking fines you can assured it's also sucking dirt via dust or dirty logs.

 

[ZeroJunk]

Anybody need a wire screen filter for an 056 that they could run with like forever. I have one.

 

[Hermio]

Not convinced that a few milligrams of wood dust ingested per gallon of 2Mix is gonna score aluminum.
Don't they use aluminum oxide to sand wood?

Aluminum and aluminum oxide are not the same thing. The oxide is very hard. Aluminum metal is rather soft. Think of it this way: iron and rust are very different. But rust is iron oxide. That having been said, is the cylinder aluminum or is it sleeved with steel?

 

[bwalker]

Aluminum and aluminum oxide are not the same thing. The oxide is very hard. Aluminum metal is rather soft. Think of it this way: iron and rust are very different. But rust is iron oxide. That having been said, is the cylinder aluminum or is it sleeved with steel?

Cylinders are mostly Aluminum coated with Silicon Carbide in a Nickle matrix.

 

[HansFranz]

Cylinders are mostly Aluminum coated with Silicon Carbide in a Nickle matrix.

Wow, silicon carbide is some HARD stuff ... also known as carborundum, they make sharpening stones out of it.

 

[bwalker]

Wow, silicon carbide is some HARD stuff ... also known as carborundum, they make sharpening stones out of it.

In part, that's why plated cylinders last a very long time. Especially in a low stress motor like a chainsaw. They other part is the hold oil better than other bore materials like cast iron.