Husqvarna 281 piston

Al Smith

Mac Daddy
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Mar 6, 2005
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Northern Ohio
These old saws are legiondary old power houses and still highly sought after .They were made before the EPA got to detuning our saws for us and making them use wimpy oilers .

This thing arrived last night with compliants it just didn't have the power it used to .Well it turned out to be too lean ,no problem just retune it .

However I thought I should peek at the piston and it was good thing I did because it had started to go bad .No biggie to repair at least to keep it workable .

I sanded it out or at least the high spots with 20 micron lapping paper and WD -40 . I just got the high spots because too much and you make the piston eliptical and it won't seal correctly .

It starts and runs and cuts just fine .I need to super tune though but it was drizzling out and I really didn't want to drown myself in the rain .Tommorrow is another day .
 

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Out of carb adjustment is a big problem out there in the everyday world. Maybe that's mainly why they went to those dandy limiters on the screws
 
If it is touchy or tricky to tune there might be a problem else were, there is often a reason they run lean, not just operators choice...
 
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Yes there could something going on with it other than just the carb being out of wack . They might have fiddled with it for all I know before I got a hold of it .

I've seen the screens partially plugged in the carb that can cause this but I never checked that out,should have though I suppose .

I have a few projects to do today but if I get them done I'll test the saw in addition to delving into that Stihl oiler thing .
 
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Flopping? Like in that tank maybe .That wasn't the problem .It was limping along just doing horizontal cuts until I tweaked it .

That thing looks to me like it has a governed carb like a 2100 .As such when it reaches a certain speed the vibrations are supposed to richen it up a tad bit .

I didn't get a chance to put it to the wood today and besides by know I've got about 3 Buds in me belly . I absolutely will not run power equipment if I have ony had one .

Tomorrow is anothar day .I'll peel the carb apart and take a look see before I put it to the wood .
 
Al, slight detour but something I've been meaning to ask you. Say you have a modified saw, one that a builder might want to stick a larger carb on to increase performance......with the stock carb, would just raising the metering lever a tad help to increase performance, i.e. more fuel provided for combustion? Been wondering about that, but too lazy to try it.

Thanks.
 
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Oh wee that's a fine line when you do that ,Yes--to a point but too much over ,even a RCH will flood it in a heart beat .

I did it with limited success on a 46 cc Poulan I ported .The danged saw used the exact same carb as a 335 Husqvarna and once I made it breathe better it just couldn't put out enough fuel to sustain high speed for over about 10 seconds . It was trial an error and I must have had that damned thing apart a half a dozen times before I got it .

What some of the racers do is hog out the fuel chamber in the carb with a Dremel . How much or where in the chamber I have not a clue . In addition you have to do pop off settings and a whole bunch of stuff .

What you might do though is just Google pop off settings .There are several real good little sites on that subject on the net .
 
Thanks. At one point I was playing around with pop off settings a lot, it was like spring city. My results were inconclusive. That is also a fine line, I believe.
 
I had trouble with a top-handle Echo that would cut out. The filter-weight that is supposed to flop to the bottom of the tank was getting wedged so it would suck some air. Fiddling with the length of the fuel line in the tank finally was the solution.
 
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Thanks. At one point I was playing around with pop off settings a lot, it was like spring city.
It gets real hairy ,so to speak . You get to chopping off a spring to change length then it changes the rate per coil rating . You can't effevtively squeeze one together but if you lengthen one it changes the dynamics and so on .

From one tiny tiny bit I know about,they say to get a bulk bag of springs before you ever start the process .It's said that no two springs will have the exact rating and you have to kind of mix and match .

Then they get to cutting out the venturi size and polishing same,larger jets .I get lost about the first turn to be quite truthfull about it .

I can rebuild one in my sleep but to really fine tune or rework a carb,I'm not the one .
 
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Fiddling with the length of the fuel line in the tank finally was the solution.
Then too you have problems at times when replacing a molded rubber type line with a plastic one .The rubber stuff is more limber it seems . The problem is ,where in the world do you find the damned stuff that will work on a saw .Most,including myself use some space age plastic in its' stead and just deal with it .
 
I've got a 280CD, had it for years but don't use it much now. It starts up, no problem and will run perfect for about 10/15 minutes then stop and won't start again.

I've been thinking about doing it up but maybe it's not worth it. We did a lot of work together once.:(
 
There is pretty much room for adjusting on a normal carb, but these EPA things with hair thin needle tip's doesn't care if it is 2 or 5 turns out as the seat will only let by a certain amount. Once open it will not get more open.

There is a easy way to test what system is giving problems.
Put some gas mix in the air filter and pull.
If it has spar it will run, if it gets no fuel it will run out shortly. If there is no spark it will have a wet plug, timing of it will be dry, smoke, but still not run...
 
If it runs fine upright but not on side could mean a number of things. Fuel line/pick up is most common, but crank seal with leak is very common to.

If it changes tone, Rpm very much or even stop when on side it is 99% of the times seal leak. It is the seal closest to ground.

If you tilt saw bar tip down and it races it is often cylinder gasket, carb boot or something like that.

A saw should be fairly easy to set. If it is tricky something is wrong!
 
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It starts up, no problem and will run perfect for about 10/15 minutes then stop and won't start again.
I had an old PM 610 Mac that did that very same thing with the exception is it would run out a tank full then not start . I tried everyting I could think of .The only thing that worked was about a 20 second cool down run prior to hitting the kill switch .

As it turned out it was all due to my ignorance .The saw was a horizontal cylinder and had a bunch of impacted chips and oil jambed under the engine that caused the cooling problem and at the time I just didn't know any better . I was smart enough to blow out the chips but not bright enough to remove the shrouding and make sure the fins were clear .--Too soon old too late smart .
 
I took it with me today to check what Jay said. Wouldn't start, thought that's it, finished. Got home and checked, spark ok, started first pull.

Put the cover back on, wouldn't start. Took it off and it started. Little crack in the old brass sparkplug connector I'd stuck on once. :|:

Got a few bits on ebay awhile back, might do it up after all. :)
 
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I finally got around to putting the 281 to the wood and would you believe the damned thing had a broken clutch spring . I half fast fixed it by joining the broken pieces back together .The closest dealer with parts is like 45 miles away .It should work fine though ,I've done it before .

So thus should end this saga of ye olde muscle saw of a bygone era at least until the next go-round which no doubt shall happen in time .Two kinds of saws,broken ones and those that will be .:lol:

At any rate the old saw did pretty good when I test drove it through some 20 inch red oak rounds .
 
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