400 hours on the same oil

[Vintage Engine Repairs]

Not a chainsaw, but rather a KM85r. Anyway, it's always interesting to assess how a particular oil performs long term when the oppertunity arrises.

This inspection is at approximately 400 hours use by my customer using 40:1 Castrol 2T Activ. He acquired it from another commercial landscaper about 6 months ago; I intend to gather details about the previous oil used and will update this thread when I know. Overall, I estimate it will exceed 800 hours of operation.

The piston skirt to cylinder clearance remains good at 0.075mm. The piston still has patches where the machining marks remain. The cylinder still maintains an as new clearance at 34.004mm. There is no play detected in the bearings and fantastic bottom end lubrication.

He said it no longer ran hence why he dropped it off. On inspection I found the rings had worn out. The ring end gap was about 1.5x the upper limit that I’d normally change them out at.

The compression is at 105 psi when I tested it. He said it was really hard to start and if it did, it quickly died…

Minimal carbon buildup in the exhaust port and crown. No blow by either! Once I gather information on the previous owner's oil usage and hours, I will add an update below.

 

[alexcagle]

Not a chainsaw, but rather a KM85r. Anyway, it's always interesting to assess how a particular oil performs long term when the oppertunity arrises.

This inspection is at approximately 400 hours use by my customer using 40:1 Castrol 2T Activ. He acquired it from another commercial landscaper about 6 months ago; I intend to gather details about the previous oil used and will update this thread when I know. Overall, I estimate it will exceed 800 hours of operation.

The piston skirt to cylinder clearance remains good at 0.075mm. The piston still has patches where the machining marks remain. The cylinder still maintains an as new clearance at 34.004mm. There is no play detected in the bearings and fantastic bottom end lubrication.

He said it no longer ran hence why he dropped it off. On inspection I found the rings had worn out. The ring end gap was about 1.5x the upper limit that I’d normally change them out at.

The compression is at 105 psi when I tested it. He said it was really hard to start and if it did, it quickly died…

Minimal carbon buildup in the exhaust port and crown. No blow by either! Once I gather information on the previous owner's oil usage and hours, I will add an update below.

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That was a good post.
Takes a long time to do that uploading and editing .

 

[alexcagle]

Here's some oranges from my shop.

 

[diver64]

This is a great post with pictures and information. That engine speaks to the oil quality it would seem to me.

 

[Sidecarflip]

Last time I checked, everything wears out, including but not limited to us. I'm sure my 'rings' are shot at 74 as well but replacement is not an easy task so they remain in place, for now. I still have pretty good compression and my spark works but is getting weaker with each passing day. I probably need a new ignition module but so long as this one fires, I'm pretty good with that.

 

[bwalker]

The ring lands look perfect. The combustion chamber and exhaust port are kinda of grungy. About what I would expect from a API TC mineral oil ran in a KM85.
I would bet it has more hours than you think.

 

[blades]

I hear ya on the neuro interface system. pump isn't firing correctly, plumbing lines are questionable over all, optics are sliding ect. 73

 

[Sidecarflip]

The ring lands look perfect. The combustion chamber and exhaust port are kinda of grungy. About what I would expect from a API TC mineral oil ran in a KM85.
I would bet it has more hours than you think.

In reality, not bad considering the hours and I've seen (first hand, I might add) how much 'grunge' buildup there is with Stihl bottled chainsaw oil and it's not pretty either. I have lost that issue 100% since switching over to Echo red Armor 50-1 or Tru-Fuel 50-1 canned gas and while not expedient to do if you are a volume user, for me it works and works well. Since switching, I've not has to de-carbon one USDA spark arrestor screen and my exhaust ports stay quite clean and free of 'grunge'. I even use it when over wintering my 4 stroke seasonal equipment. Sure saves me the time and effort to clean gunked up carbs every spring from the adverse effects of corn squeezed e-gas. As it is, I still clean gunked carbs for friends and customers. I submerge them in my large heated ultrasonic cleaner with Berrymans B12 Chem tool which handily cleans them of phase shifted e-gas crud, especially motorcycle carbs when the bikes sit all winter and the e-gas degrades and plugs them up.

 

[bwalker]

In reality, not bad considering the hours and I've seen (first hand, I might add) how much 'grunge' buildup there is with Stihl bottled chainsaw oil and it's not pretty either. I have lost that issue 100% since switching over to Echo red Armor 50-1 or Tru-Fuel 50-1 canned gas and while not expedient to do if you are a volume user, for me it works and works well. Since switching, I've not has to de-carbon one USDA spark arrestor screen and my exhaust ports stay quite clean and free of 'grunge'. I even use it when over wintering my 4 stroke seasonal equipment. Sure saves me the time and effort to clean gunked up carbs every spring from the adverse effects of corn squeezed e-gas. As it is, I still clean gunked carbs for friends and customers. I submerge them in my large heated ultrasonic cleaner with Berrymans B12 Chem tool which handily cleans them of phase shifted e-gas crud, especially motorcycle carbs when the bikes sit all winter and the e-gas degrades and plugs them up.

Well, Stihl oil is the lowest quality OEM oil. The orange bottle is probably about on oar with Castrol Active.
If you are having to clean spark screens you have a tuning issue. I have literally never had one that needed cleaning not matter what oil was used.
I have used Red Armor for the last couple years in everything and ai really like it.

 

[Sidecarflip]

I hear ya on the neuro interface system. pump isn't firing correctly, plumbing lines are questionable over all, optics are sliding ect. 73

My 'optics' slid to the point where I was playing 'Helen Keller' a lot so I had them (lenses) replaced and now they work as intended but my wife always tells me I have ' selected vision' and I agree but more so, I have selected hearing as in I only hear and process what I want to and everything else I tend to ignore. I do have a nice set of hearing aids that I hardly ever wear simply because a lot of things I don't want to hear anyway.

 

[Sidecarflip]

Well, Stihl oil is the lowest quality OEM oil. The orange bottle is probably about on oar with Castrol Active.
If you are having to clean spark screens you have a tuning issue. I have literally never had one that needed cleaning not matter what oil was used.
I have used Red Armor for the last couple years in everything and ai really like it.

So do I but in my case and the amount I use predicates using their 50-1 canned gas. One thing I do like about it is the shelf life which is 5 years in an unopened can or 2-3 years in my gas can I use to fill the saws. Besides, the unopened cans fit nicely on the shelf above where I store my saws. I currently have 2 cans up there and one can in the gas can I use to fill the saws and that gas can is an old style (pre EPA safety spout) plastic can. The new EPA approved gas cans are all basically shitte.

 

[blades]

selective hearing -ex accused me of that eons ago- it is more selective now.

plastic gas cans-epa, real fun when they blow up in the back of truck under bed cover from summer heat/sun combo. which I have had a couple do. Balancing a 5gal jug of diesel 4 ft in the air to make that no leak spout work is a real treat on my tractor.

 

[bwalker]

So do I but in my case and the amount I use predicates using their 50-1 canned gas. One thing I do like about it is the shelf life which is 5 years in an unopened can or 2-3 years in my gas can I use to fill the saws. Besides, the unopened cans fit nicely on the shelf above where I store my saws. I currently have 2 cans up there and one can in the gas can I use to fill the saws and that gas can is an old style (pre EPA safety spout) plastic can. The new EPA approved gas cans are all basically shitte.

I have used some of the red armor fuel that I got on sale. 3 gallon as I recall. After that ainswitched to Harvest King 4 cycle fuel that ai mix with Red Armor. It's the cheapest alkylate fuel ai have found.

 

[diver64]

selective hearing -ex accused me of that eons ago- it is more selective now.

plastic gas cans-epa, real fun when they blow up in the back of truck under bed cover from summer heat/sun combo. which I have had a couple do. Balancing a 5gal jug of diesel 4 ft in the air to make that no leak spout work is a real treat on my tractor.

The silly "safety spout" is a nightmare. I immediately replace all of mine with a standard spout and seperate vent you can buy at TSC or online. The vent will pop open if the pressure gets too high from heat.
https://www.tractorsupply.com/tsc/product/ez-pour-hi-flo-replacement-spout