Problem 026

[Carhartt]

I have a nice looking 026 red lever. Will start and run fine but will not stay idling and when you hit throttle it stalls like L is lean.

What I have done so far.
compression 145ish
fuel line/filter
impulse line
inspect intake boot(no cracks)
new spark plug
pressure test to 10 psi overnight and held ( I do not have vaccum)
3 different carbs, 1 new , 1 rebuilt
I do not see any areas where fuel could puddle between intake and cylinder.

I am out of ideas.

 

[Stump Shot]

First, check your muffler screen for plugging.
If that's clear start looking at your ignition coil for good spark.

 

[Wood Doctor]

Make sure the carb air filter is really clean. These are notorious villians that make an 026 run lousy. Change it out as needed. Also, try opening up the hi-speed setscrew a half turn.

 

[Carhartt]

Turned every screw ten times. Air filter is new wire mesh type.
I will chk coil. Not a whole lot left.
Not kinked or pinched fuel line either.

 

[drf256]

Pull the jug and match to boot the best you can, looking both ways. Sure sounds like puddling.

 

[drf256]

Where are your carb screws now?

Really need a vac test. Seals can hold one way and not the other.

 

[BuckthornBonnie]

Yes to above and, lastly, check the flywheel side seal. You mentioned no vacuum test, so that’s something we haven’t eliminated.

There’s a shadetree way of doing this that I do but don’t recommend to most people. You can spray the suspected area with carb cleaner while it’s running. A leak would kill the saw.

It doesn’t sound like a conventional air leak, but let’s not assume anything yet.

 

[drf256]

Sometime an air leak will cause the L screw to be set way out at idle. That can cause some puddling, as it will pull a lot of fuel while winding down from WOT.

I’d double check the flywheel key also. If it slipped/sheared, it can cause an odd situation where it needs to be richer than usual for idle and cause puddling.

Not to say your issue is, but it’s a model specific problem. When I build a ported 026, the user has to be aware that idle and off idle issues may be there. Generally they need to be set a bit lean on idle and spoolup will have a slight delay. If set richer at idle, the spoolup will be normal, but the saw will shudder if it sits idling for more that 15-20 seconds. It will start to load up and will need a few blips to get back to a normal condition. The blue Ducati coil seems to stop that for some reason. The standard scalloped bodied coil makes it happen more. They are both dummy coils, but one probably supplies more advance.

These are my experiences, YMMV.

 

[Carhartt]

Fly wheel key was on my list. I am not the original owner of this saw so anything is possible.

Everything you are saying is kinda spot on. set the carb up by normal routine and it will come down off high rpm fine and then 8 to 10 sec later start to sputter and then stall.

Lets say puddling is the answer. Is grinding and sanding the only answer? If you cant see an obvious spot of puddling where do you start removing? Low left corner?

Oh and very doubtful its muffler screen. Screens come out right away on my saws. Its possible I missed it and will chk also.

 

[trooney]

Just what happened to me. Had an 024S that had symptoms like it was puddling fuel. No matter what I did with the carb, it would act the same. Tried a couple different known good carbs, same thing. Passed a pressure and vac test many times. I was getting ready to throw her against the wall (not really) and it was suggested that I replace the seals. The clutch side looked brand new but the flywheel side was old. Replaced that and she ran good. Not saying thats your problem, but its just one of those things I wouldnt think of because it passed a preesure/vac test. Live and learn. Seals are cheap...

 

[Bilge Rat]

Try rotating the crank during a vac test.
Slowly move it a little bit then see if there is a drop on the gauge.

Have you tried turning it side to side at idle?

 

[Carhartt]

So here is what I got. Tore it all apart, cleaned what I cld. Reinstalled intake boot, pulled new impulse through, readjusted coil, wrapped plug wire, new plug and slid on the rebuilt carb (original oem). It fired up and some slight carb adjustments it runs ok. It will idle for some time now and not stall. But it does load up when burping the throttle after long idle. Seems to change rpm mildly when you shake the saw front to back on idle. I suspect I got a puddling problem and I might have slightly altered the boot different on the reinstall and maybe seated it tighter on the cylinder flanges allowing it to run to what I would call satisfactory. It does not have a sweet low idle like other saws but the chain isnt moving. I have a few pics inside boot I'll try and upload.
Oh and I looked I did remove the screen from muffler way back when.
I'll put some fuel through and see what it does or doesnt do over wknd.

 

[Carhartt]

 

[drf256]

That’s an OEM jug? Never seen a casting line like that in an intake floor. Looks huge. The boot looks smaller than the port by a bunch at the floor. Sometimes it can puddle there too, depending on how saw is sitting.

If that’s an AM jug, anything is possible. The timing can be all over the place. Too much intake can make a saw idle oddly.

I’d pull jug and smooth that floor out for certain. Check piston to bore clearance. Should be less than .003.

Like Trooney said above, you can swap out the seals and see if it helps. AM seals are actually ok if you have the ability to swap out easily at anytime. I generally stick with oem though. It’s usually the flywheel side.

 

[Carhartt]

OEM cylinder. I think I replaced the rings/maybe piston and rings when it came to me many moons ago. I am going to run some fuel through it and see if it acts up. If so ill tear it down again and polish and replace seals. I cant complain about Farmertec seals, they have worked decent for me in most recent repairs and have a set off to the side for this saw.

 

[PogoInTheWoods]

Try just holding it in the air by the front handle to observe the idle instead of setting it down and see what happens. An older intake boot combined with tired and worn a/v can deform just enough with the saw in different positions and weight distribution to cause erratic idling. More likely to occur on a larger/heavier saw, but still a possibility on a smaller one.

 

[fossil]

Not sure of the symptoms but any chance it might be one of those air filters that the choke flap is closing?

 

[Carhartt]

No it ran the same with or without the air cleaner. Made a dozen cuts with it over wknd and seems to be working ok. No stalls but still loads up after idle for 30 seconds. Doesnt stall when you hit the throttle but isnt a fast response. If idle for 3 to 5 sec it picks up fast. I advanced the timing a smidge. Seemed to help a little.

 

[drf256]

No it ran the same with or without the air cleaner. Made a dozen cuts with it over wknd and seems to be working ok. No stalls but still loads up after idle for 30 seconds. Doesnt stall when you hit the throttle but isnt a fast response. If idle for 3 to 5 sec it picks up fast. I advanced the timing a smidge. Seemed to help a little.

It’s the plague of the 026, I had some that just did that.

Try a blue Ducati coil. If you wanna borrow one just to see if it works, it can be arranged.

I just did a day trip to State College PA on Saturday, too bad. About as “Central” PA as one can be.

I’d still get rid of that casting flaw on the intake floor if I were you.

 

[PogoInTheWoods]

Call me lucky. I have three 026's. Two bone stock. One with a very early NWP top end from Bailey's years ago. Two WT22's and a WT194. All run great. None exhibit the problem being discussed.

They have a reputation for being finicky for sure. Also have a reputation for being a pretty bad ass little saw even with the quirks. If yours loads up on idle when you set it down, shut it off instead. If it doesn't fire right back up with one pull, you may be further out of adjustment than you think, or indeed have other issues -- possibly ignition as alluded to.

Ditto on the casting flaw. Easy enough to eliminate as a possible contributing factor.