Signs of 460 running lean

[Onelick]

I just put the factory Stihl muffler mod on my 460 and had the tech retune the carb. My question is: (I've searched, but couldn't find anything.) I'm not sure the tech did it correct. The guy they did have left to start his own business, and the one that adjusted mine is just one of the guys that helps around the rest of the business. He didn't look to see if it had a clean air filter (it was, of course) He ran it WOT and the tach read 13475-13600, if the tech manual says 13,500 is this within spec's? If he did not do this correct, what signs should I look for if it is running lean? I'm going to be clear cutting a building site this weekend, and it's going to be run hard and I don't want to burn the piston up.
Thanks, Onelick

 

[computeruser]

http://www.madsens1.com/sawtune.htm

 

[Lakeside53]

I just put the factory Stihl muffler mod on my 460 and had the tech retune the carb. My question is: (I've searched, but couldn't find anything.) I'm not sure the tech did it correct. The guy they did have left to start his own business, and the one that adjusted mine is just one of the guys that helps around the rest of the business. He didn't look to see if it had a clean air filter (it was, of course) He ran it WOT and the tach read 13475-13600, if the tech manual says 13,500 is this within spec's? If he did not do this correct, what signs should I look for if it is running lean? I'm going to be clear cutting a building site this weekend, and it's going to be run hard and I don't want to burn the piston up.
Thanks, Onelick

That's "within spec" - or as close as you are going to get on any given day... Check it tomorrow, it will have changed slightly. However, remember that this number is a NEVER EXCEED speed...

You DON'T have to tune it to WOT MAX. If you are worried, just turn it back slightly (counter clockwise) to 12,500 to 13,000. You'll hear the muffler tone lower and maybe more 4-stroking, but it won't make but a hair of difference in cut times, and you'll have peace of mind.

 

[whatsnext]

That's "within spec" - or as close as you are going to get on any given day... Check it tomorrow, it will have changed slightly. However, remember that this number is a NEVER EXCEED speed...

You DON'T have to tune it to WOT MAX. If you are worried, just turn it back slightly (counter clockwise) to 12,500 to 13,000. You'll hear the muffler tone lower and maybe more 4-stroking, but it won't make but a hair of difference in cut times, and you'll have peace of mind.

Excellent advice. I've never seen a saw seize form being run slightly too rich. I know there are good reasons for maximizing a saw's output but for 95% of us keeping the saw in one piece is more important.

 

[musher]

Is it safe to assume that tuning the saw to the specified max RPM without bar and chain will cause the saw to be more rich than if tuned with bar and chain attached?

I would assume that tuning with bar and chain on to the factory max would cause the saw to be more lean the heavier the load (longer bar/chain), and it doesn't make sense to me to do that to the saw.

 

[Lakeside53]

Is it safe to assume that tuning the saw to the specified max RPM without bar and chain will cause the saw to be more rich than if tuned with bar and chain attached?

I would assume that tuning with bar and chain on to the factory max would cause the saw to be more lean the heavier the load (longer bar/chain), and it doesn't make sense to me to do that to the saw.

If you insist on tuning to max rpm, then tune it with the bar an chain on - that's how Stihl specs the WOT on all their saws. If you don't load the saw up a little, WOT setting is not reliable and on some smaller saws, you end up really rich. Some saws won't have a clear "4-stroking" point unless there is the chain load, and some don't even with it on.

 

[wradman]

saw setting

i wouldn't recommend setting the saw without the bar and chain, just do it right once and make sure the filter is clean, also set it with the fuel you use not the fuel from the saw shop.

 

[pbtree]

i wouldn't recommend setting the saw without the bar and chain, just do it right once and make sure the filter is clean, also set it with the fuel you use not the fuel from the saw shop.

What he said...

 

[musher]

So, why do I get a different impression from http://www.madsens1.com/sawtune.htm (see #8, where they list max RPM settings for some saws)? Are they just wrong there?

 

[Kneejerk Bombas]

So, why do I get a different impression from http://www.madsens1.com/sawtune.htm (see #8, where they list max RPM settings for some saws)? Are they just wrong there?

Wrong about what?
Set the RPMs at or slightly below recommended maximum.

 

[Onelick]

Thanks for all the info. That link to madsen's really helped me understand it better.
Onelick

 

[musher]

Wrong about what?
Set the RPMs at or slightly below recommended maximum.

Wrong about tuning to the numbers without bar and chain . . .

 

[wradman]

musher

i'm with you musher what's there to fight about just put the freaki8ng bar and chain on

 

[musher]

Hey, I'm just trying to understand, and to reconcile what seems to me to be conflicting information, that's all.