wood dust in the carb hard on the saw?

[bwalker]

So technically an oil problem.. specifically lack of for the job at hand.

That's not a oil problem at oil. If the air filter was functional there would be no problem.

 

[Bob Hedgecutter]

That's not a oil problem at oil. If the air filter was functional there would be no problem.

Hang on a mo- @trains said it was likely 50:1- it was running a ****** Dink filter- it was a 460 on a mill, milling Aussie timber- put all those together and Id expect the saw to be dead within a few months if not sooner.
Now if the original owner was running two 460's side by side in same conditions- one as above and the other OEM and tuned on 33:1 or even 25:1- are you saying the results would be the same?

 

[bwalker]

Hang on a mo- @trains said it was likely 50:1- it was running a ****** Dink filter- it was a 460 on a mill, milling Aussie timber- put all those together and Id expect the saw to be dead within a few months if not sooner.
Now if the original owner was running two 460's side by side in same conditions- one as above and the other OEM and tuned on 33:1 or even 25:1- are you saying the results would be the same?

If indeed it was ingesting to much fine the oil was wiped away, that's not an oil problem.
You are preaching to the choir on running something like 32:1.
However if your ingesting so much junk that it's wiping oil away, that's not an oil issue.

 

[Bob Hedgecutter]

If indeed it was ingesting to much fine the oil was wiped away, that's not an oil problem.
You are preaching to the choir on running something like 32:1.
However if your ingesting so much junk that it's wiping oil away, that's not an oil issue.

Me, Id say heat, long continual cuts in hard timber and 50:1 ratio compounded what you are seeing as because of the aforementioned issues, there was never enough oil there in the first place- so that might be an "oil issue"- but you are set in stone on your train of thought- all power to you- we can agree to disagree.

 

[rogue60]

How I sleep knowing sawdust fines are getting past my air filter.

 

[HansFranz]

If indeed it was ingesting to much fine the oil was wiped away, that's not an oil problem.

Seems to me that you would need a LOT of "fines" getting past the filter (like say a tablespoon-full if not a shotglass-full per tank of 2mix consumed) to absorb enough oil at 32-to-1 or even 40-to-1 to get wear due to an "oil problem."

My hunch is that it's more due to any silica in the fines (probably much more a problem with Oz hardwoods than anything here) ... but again, I think we're talking about "polishing compound" if not "jeweller's rouge" grit sizes and quantities...

 

[rogue60]

Seems to me that you would need a LOT of "fines" getting past the filter (like say a tablespoon-full if not a shotglass-full per tank of 2mix consumed) to absorb enough oil at 32-to-1 or even 40-to-1 to get wear due to an "oil problem."

My hunch is that it's more due to any silica in the fines (probably much more a problem with Oz hardwoods than anything here) ... but again, I think we're talking about "polishing compound" if not "jeweller's rouge" grit sizes and quantities...

It's a bit of a head scratcher kind of..
If high silica content was to blame wouldn't it be ground into an abrasive sludge and move through the whole engine leaving some evidence?. Oil/fuel enters through the intake and seems to find every nook and cranny. I can't see why an abrasive mixed in wouldn't do the same?.
The exhaust side of the piston is in remarkably good shape its only the bottom of the skirt that shows wear from piston rock? the rest of the piston skirt still has machine marks and no evidence of abrasive scoring. I think we can safely say any sawdust fines that saw ingested as not being aggressively abrasive?.

We can only guess what the intake side of the piston looked like before the oil film started braking down? Presumably from sawdust fines wipping the oil away in this case and allowing metal to metal contact. Which = heat and it wouldn't take long for the piston to start smearing and melting itself up and down the cylinder wall with no oil film left to speak of.
The intake piston/skirt damage we are seeing is from metal to metal contact that's not debris damage scoring it was actually seizing on the intake side of the piston.
But like I say we don't know what the intake side of the piston looked like before this it may of shown debris ingested scoring or excessive wear who knows?
IMHO I believe more oil or even a better quality oil? may have prevented an oil film brakedown thus not allowing metal to metal contact as has happened in this case, even with a dodgy nock off air filter letting fines in. Flame away lol

 

[bwalker]

Seems to me that you would need a LOT of "fines" getting past the filter (like say a tablespoon-full if not a shotglass-full per tank of 2mix consumed) to absorb enough oil at 32-to-1 or even 40-to-1 to get wear due to an "oil problem."

My hunch is that it's more due to any silica in the fines (probably much more a problem with Oz hardwoods than anything here) ... but again, I think we're talking about "polishing compound" if not "jeweller's rouge" grit sizes and quantities...

I would agree.

 

[bwalker]

It's a bit of a head scratcher kind of..
If high silica content was to blame wouldn't it be ground into an abrasive sludge and move through the whole engine leaving some evidence?. Oil/fuel enters through the intake and seems to find every nook and cranny. I can't see why an abrasive mixed in wouldn't do the same?.
The exhaust side of the piston is in remarkably good shape its only the bottom of the skirt that shows wear from piston rock? the rest of the piston skirt still has machine marks and no evidence of abrasive scoring. I think we can safely say any sawdust fines that saw ingested as not being aggressively abrasive?.

We can only guess what the intake side of the piston looked like before the oil film started braking down? Presumably from sawdust fines wipping the oil away in this case and allowing metal to metal contact. Which = heat and it wouldn't take long for the piston to start smearing and melting itself up and down the cylinder wall with no oil film left to speak of.
The intake piston/skirt damage we are seeing is from metal to metal contact that's not debris damage scoring it was actually seizing on the intake side of the piston.
But like I say we don't know what the intake side of the piston looked like before this it may of shown debris ingested scoring or excessive wear who knows?
IMHO I believe more oil or even a better quality oil? may have prevented an oil film brakedown thus not allowing metal to metal contact as has happened in this case, even with a dodgy nock off air filter letting fines in. Flame away lol

I have had motocross bikes suck in sand. The damage is worse on the intake, but it's every where. So yea, damage to the intake side only is a head scratcher.

 

[Bob Hedgecutter]

Seems to me that you would need a LOT of "fines" getting past the filter (like say a tablespoon-full if not a shotglass-full per tank of 2mix consumed) to absorb enough oil at 32-to-1 or even 40-to-1 to get wear due to an "oil problem."

My hunch is that it's more due to any silica in the fines (probably much more a problem with Oz hardwoods than anything here) ... but again, I think we're talking about "polishing compound" if not "jeweller's rouge" grit sizes and quantities...

Now with 2 strokes having no sump and all- no separate oil lubrication system, the oil you add to gasoline lubricates the internals of the engine- yes?
Should you be adding sufficient silica to the mix, would it not go to all the places that oil should go and cane out all those rotating bits like ball and needle bearings before tearing just one side off of the piston?

What was the original question on this thread? Has the original poster been back? Was there a bet made about lets start a post and see how long it takes to become an oil thread?

 

[HansFranz]

Was there a bet made about lets start a post and see how long it takes to become an oil thread?

All threads become oil threads eventually. It's like a law of nature.

 

[stihltech]

Lets go back to the old mesh air filters in 031, 032, 045, 56,etc. When they did not get cleaned, they would actually suck part of a piece of the filter into the saw. Had a few do it.

And now we are worried about a few fines?

Move on.

 

[North by Northwest]

All your pistons show excessive skirt wear.
There is nothing wrong with expecting an air filter to actually filter.

Well used high hr saws !

 

[North by Northwest]

k&n filters have a oiled cotton( may be synthetic at this point) media between the metal. Not great for a Mass airflow sensor, but good filtration otherwise. Foam filters work off much the same principal for filtration. Both used extensively in harsh environments. The oil does as much work as the media holding it.

Your absolutely correct Sean , K&N have synthetic foam fibre with re-enforced metal cage that are impregnated (treated) at the factory with tacky oil based solution then bagged prior to shipping . A very effective air filtration . Unifilters from Austrailia are even more effective . I have had several quads & sidebys with these filters . Nothing sees more fine dirt particulate than Atv / Utv's brother !

 

[ZeroJunk]

When you take a notion to rebuild one of those Gunk Engine Cleaner and a garden hose work AOK.

 

[bwalker]

Your absolutely correct Sean , K&N have synthetic foam fibre with re-enforced metal cage that are impregnated (treated) at the factory with tacky oil based solution then bagged prior to shipping . A very effective air filtration . Unifilters from Austrailia are even more effective . I have had several quads & sidebys with these filters . Nothing sees more fine dirt particulate than Atv / Utv's brother !

It's actually cotton gauze. The flow good, but don't filter all that well.

 

[bwalker]

Lets go back to the old mesh air filters in 031, 032, 045, 56,etc. When they did not get cleaned, they would actually suck part of a piece of the filter into the saw. Had a few do it.

And now we are worried about a few fines?

Move on.

Let's just get rid of filters all together.

 

[rogue60]

Let's just get rid of filters all together.

Might as well they don't filter out fines very good do they. Might pick up .3 of a hp also?
Actually I've tried no air filter before couldn't notice any gains worth mentioning myself..

 

[stihltech]

Might as well they don't filter out fines very good do they. Might pick up .3 of a hp also?
Actually I've tried no air filter before couldn't notice any gains worth mentioning myself..

Operators don't clean any of them, so what is the point.
It's maintenance. And as long as the better (?) filters require more maintenance, they are not better.
I am betting the original equipment manufacturer thought about that when they when they were designing the saw.
Maybe a filter that draws air from the bottom without restriction would be best. So the sawdust can fall back off. And no, not the MS170 style.
But somebody would find a way to plug that too.

 

[HansFranz]

Let's just get rid of filters all together.

Or let's use those oil bath filters like they use on tractors...