The chainsaw thread...

[bodywhomper]

I've been happily sawing with my newly revived ms361 quite a bit lately until this evening, when in the middle of a big cut wot, it starts revving like crazy (full tank of fuel). the idle seems unchanged. Under no load, i open the throttle and it accelerates well to where i had set the carb but then keeps revving higher. Release the throttle and it slowly revs down to idle, slower than previously, and it almost seems to hang up in what seems like a half throttle. It was starting to get hot, too. So something suddenly changed today ( i cut wood for a little under 2 hours today; all long cuts bucking big logs) that's making it run lean with open throttle. Fuel filter/pickup? That's something that i have not yet replaced. Would it cause a sudden change like that?

Looking for advise. The saw is still acting funky when the throttle is open: constantly fluctuating between racing, then bogging, then fine, then racing, etc., all within 10-20 seconds. This is after I replaced the fuel pickup/filter, air filter, and spark plug (confirming that the plug gap had been adjusted correctly), readjusted the carb with a full tank and alwarmed engine, used it for 3/4 a tank, and refueled. The gas is high octane and less than 1 month old (stabilizer added). Fuel hose is recently replaced.

Air leak, impulse line, and/or carb? Or something else? I don't think I have the tools to check pressure. I have a bike floor pump and fork pump. Is there a way to rig a connection?

Thoughts?

[Flake]

I have a couple of saws Stihl ms180 and ms390. The little one is light and handy for brushing, limping and cutting up windfalls etc. If you are cutting a lot the bigger saw with the longer bar is easier on the back. Less bending over because the saw does the reaching for you.
Chains should last a guy for a long time if you are careful and don't rock them. If freehand sharpening isn't your thing a saw shop should have sharpening guides. The ones I use are tiny little things that just keep your file angle consistent. With them I can make a nice sharp saw that cuts straight. Freehand sharpening isn't for me.

[Flake]

These things are what I was talking about

[rbtree]

Get a full skip chain.

Wrong answer. Full skip is only for long bars, to aid in chip clearance.

[rbtree]

Looking for advise. The saw is still acting funky......

Air leak, impulse line, and/or carb? Or something else? I don't think I have the tools to check pressure. I have a bike floor pump and fork pump. Is there a way to rig a connection?

Thoughts?

You asked about the only three things it could be. Ignition issues can't cause the problems you describe, which leave the fuel system, and you've checked/ replaced everything else. I'd suggest finding a competent guy at a repair shop to do pressure/vacuum tests and or install a carb kit.... you could also join chainsawrepair.com and ask there. Besides the site owner, an online friend, there's plenty of saw gurus there....

Good luck, and if you wanna see some vid's of me and my crew doing tree work, check out my youtube channel its rbtree......

[rbtree]

These things are what I was talking about

Great tool, probably the best chain filing aid. As I've been working in the trees for 45 years, I don't need or use a file guide, but that's the one to use.

[rbtree]

Holleee crap. I'm trying to cut up some small trees 10"-12" dia near the house and my 450 Rancher is just struggling and smoking chains in the stuff. I pull out the 372XP and its doing a bit better but dulling chains like crazy. The chain oilers are on max. I'm using a Oregon 73 low kick chain on both saws.

Any chain suggestions on how to get this stuff carved up faster or am I doomed? From the tree guide this seems to be American hornbeam. Nasty stuff.

Hornbeam is about as hard as domestic woods come. That said, it shouldn't dull your chain that quickly. Ensure that the logs are clean and free of foreign matter...dirt, embedded rocks, etc. But, above all, don't cut into the ground. Watch your bar tip. Elevate the log if possible.

[XXX-er]

Great tool, probably the best chain filing aid. As I've been working in the trees for 45 years, I don't need or use a file guide, but that's the one to use.

yeah thats ^^ the one I use, as long as the rollers are turning and you are in the middle of the guide its ALMOST idiot proof

- there are 2 colors the blue guide is for 3/8ths" chain and the silver guide for .325"

- its asymetrical so there are arrows on the guide that should point forward, so I don't forget I put some colored marker on the forward edge to remind me which way is forward

yeah if you touch the dirt even once you will be filling, we have been cutting in a foot of snow which keeps the trees up off the ground and we are still cutting ski run

As for the saw not running well problem I have heard of people yarding on a saw when its stuck which tears the rubber carb boot between the saw and carb so it leaks air which leans out the mixture ?

[bodywhomper]

These things are what I was talking about

^^^That's the guide that im using.

I think i duffed a chain bucking in twilight. I get some dust and some shavings currently. What do peeps do to determine if their chain is sharp? Ive read a few methods....

[Meadow Skipper]

Look at the chips it's throwing - you want nice big same-sized ones. Dust means time to get the files out.

You can also look at the teeth - sharpen one and compare it to the others.

[rbtree]

Yup, you got it good.... Chisel chain is especially dependent on having a sharp point, which dulls easily.

You're using a good guide, but one way to determine if the tooth is sharp is to look for reflected light. A sharp edge doesn't reflect any..... glasses, or magnifying reading glasses, can help.... I have special magnifying headband which really helps.

Also, be sure to maintain the depth gauges......

[bodywhomper]

Thanks. That's all helpful!

Meadow skipper, im getting both fairly long chips and dust, which indicates to me the brief ground strike on part of the chain.

It was super hard to tell at the time: headlamp, wet manzanita, wet duff, probably the last cut before i called it, etc. Did i get thr duff or not...? Also some logs were pretty dirty; i tried to wipe them off with wet gloved hand...

[Meadow Skipper]

Meadow skipper, im getting both fairly long chips and dust, which indicates to me the brief ground strike on part of the chain.

Probably so. It happens. rbtree's got it - sharp edges look different than dull ones.

[Bronco]

Sounds like you nicked something with a few teeth and others are still throwing good chips. It's never a bad idea to sharpen the chain if you're in doubt.

[bodywhomper]

Yep. I did a bunch of file passes on all the cutters. I'll look closely at all the cutters when back at home. On another note, finally going to getting my bigger (for me) saw running and tuned this next week, and I'm getting a log roller (cant hook) with 5' handle. pge is comin soon to drop more of our pines. I have lots of sawing and saw-type projects with the pines, and harvesting some larger long dead manzanita for burning this winter. (Somehow need to stay employed and not derail skiing)....

[~mikey b]

You guys seem to have a lot of trouble sharpening your saws. It ain't rocket surgery...

Careful with manzanita. Burns super hot. You can damage your stove. And old dead manzanita is hard on chains. Good luck

[bodywhomper]

The sharpening is just a learning curve thing for me, I think.

Agree about the manzanita....

[Bronco]

Oh yeah, if the cutter teeth are in good shape, check the raker tooth height, that can produce the symptoms you've described.

[bodywhomper]

Thanks.

[riser4]

How annoying was I being when I got the Stihl out to cut an inch off the bottom of the Christmas tree at 8:20 PM? 30 seconds of noise for a much better cut than i can do with a handsaw, especially in the dark. It was a school night too. I do love me my old school .017. It has been running a lot better lately. And since I use it very rarely, I tend to make sure it has the $12 pre-mixed fuel in it when I am done. That has probably helped the most.

[XXX-er]

sounds^^ like a huge waste of time

I just used a pruning saw

[bodywhomper]

I use premix in my weedwacker, which gets used 4 times a year at most.

[bodywhomper]

Back to the rocket science of chain sharpening, anybody have experience using this raker height/angle tool? It's different that's the other husqvarna raker tool that I have and I'm struggling more than I'd suspect to figure the damn thing out.... <noob>

[XXX-er]

whatever of the raker sticks up in the slot of that guage needs to be filed down

as for what Husky calls " the combi guage " :

-make sure you got the right color cuz the aluminium colored guage is for .325 and the blue anoidized is for 3/8ths chain
-look on the arrows cut into the frame of the guage they MUST point forward
-put the gauge on the chain, run the file parallel to the line etched on the tooth with both rollers turning and you are good
-Twist the file while moving it forward and you will feel it bite better
-do the same number of strokes on each side
-the number of strokes you do depends on how much you fucked up the chain so experiment with what you need

I file every 5 or 6 hr day of running the saw at the very least, the saw will run/faster/smoother with much less effort with a sharp chain

Its faster to carry 2 chains that you sharpened at home than to waste time filing a chain in the bush instead of cutting

[bodywhomper]

Thanks.

That one pictured is for a 3/8 mini/picco chain. That raker thing is different than what they sell for the standard 3/8 and .325 chains, and the instructions nor anything else that I see online covers use of that different tool. The raker gauge for the other husky guides is more simple to me. That one pictured in my post doesn't seem to give options for wood hardness.