tuning a saw for milling

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Lester Gillett

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I have read a lot of post about how to set up your saw for milling. They all say you need to tune your saw for the more oil you use.
I have a stihl ms460 with a 36" bar. I use a 40:1 mix but last time i burned the piston. Now before I use it after rebuilding can some
one give me a detail instruction on how to adjust my saw to match the oil mix i am using. Is there any videos showing how or is there
some one close to me that can help me adjust it. I live in Independence Mo and i have some large oaks i need to mill. Any help would
be grate full so i don't burn it up again.
Lester
 
I have read a lot of post about how to set up your saw for milling. They all say you need to tune your saw for the more oil you use.
I have a stihl ms460 with a 36" bar. I use a 40:1 mix but last time i burned the piston. Now before I use it after rebuilding can some
one give me a detail instruction on how to adjust my saw to match the oil mix i am using. Is there any videos showing how or is there
some one close to me that can help me adjust it. I live in Independence Mo and i have some large oaks i need to mill. Any help would
be grate full so i don't burn it up again.
Lester
Did you vac/pres test after fixing it?

PDF below is good and has links to Lo/Hi adjust
 

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Did you vac/pres test after fixing it?

PDF below is good and has links to Lo/Hi adjust
No i haven't fixt it yet. Going to as soon as i receive the parts. I see you say to vac/pres test after fixting, is that to make sure the seals and gasket are ok ?
I will have to see what i have to block off the carb and muffler. I do have the vac/pres tool. will see about a tech to check rpm on my saw and on some
ts400,420 saws. Thanks for he info and may be i will not burn up it next time.
 
No i haven't fixt it yet. Going to as soon as i receive the parts. I see you say to vac/pres test after fixting, is that to make sure the seals and gasket are ok ?
I will have to see what i have to block off the carb and muffler. I do have the vac/pres tool. will see about a tech to check rpm on my saw and on some
ts400,420 saws. Thanks for he info and may be i will not burn up it next time.
I'd check it before and after. The link I posted show what the saw should sound like.
 
I'd check it before and after. The link I posted show what the saw should sound like.
+1 for that...
If you haven't pulled it apart yet vac/pressure test it before you do to see if that was the problem. You don't need anything special to block things off, just cut up an old inner tube to make a seal between the carb/muffler & saw.
Make sure you check it again once you've fixed it.
With regards to tuning, the tach is probably your best bet if you're not familiar with the process of tuning by ear...
Start by mixing fresh fuel as you intend to run (for milling I use a quality synthetic oil at 32:1 with non-ethanol fuel). Set the carb to factory as per the manual, allow saw to warm up & then tune L as per manual/prior instructions & using the tach, tune max RPM to ~500RPM below saws listed max.
Keep us posted
 
Just to make things clear.

It's not necessary to use more lube in fuel mixes used for milling than recommended for regular chainsaw use. Todays saws are designed to run indefinitely at WOT on what the manufactures state in their manual (usually 50:1) provided you use the quality 2 stroke oils stated in the saw manuals. The manufacturers are actually being conservative and their saws could even run at 100:1 on fully synthetic lubes. The reason the manufactures don't put this in the manual is because its very difficult to accurately mix 100:1 ratios and you don't want to run the risk of getting it wrong. More lube just means more unburnt oil (plus other additives in the lube like smoke suppressors) comes out of exhaust and fogs the air around the operator.

However If fuel (gas/lube) mix ratios are changed it is important to retune to that mix .

What is also important is to drop the max revs of the saw by about 500 rpm so the saw runs a little richer but this has nothing to do with the gas oil mix.
 
Just to make things clear.

It's not necessary to use more lube in fuel mixes used for milling than recommended for regular chainsaw use. Todays saws are designed to run indefinitely at WOT on what the manufactures state in their manual (usually 50:1) provided you use the quality 2 stroke oils stated in the saw manuals. The manufacturers are actually being conservative and their saws could even run at 100:1 on fully synthetic lubes. The reason the manufactures don't put this in the manual is because its very difficult to accurately mix 100:1 ratios and you don't want to run the risk of getting it wrong. More lube just means more unburnt oil (plus other additives in the lube like smoke suppressors) comes out of exhaust and fogs the air around the operator.

However If fuel (gas/lube) mix ratios are changed it is important to retune to that mix .

What is also important is to drop the max revs of the saw by about 500 rpm so the saw runs a little richer but this has nothing to do with the gas oil mix.
I use one of these, and rinse the oil out into the gas can.

1 volumetric.png
 
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