Awesome tip, will try it, thanks! I want to start searching for parts and don't have time just yet to tear the saw apart.
Stihl 028WB top end
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unless you are going to source 'everything' you might want to see what you need by tearing it down first and inspecting everything first....just a thought.
Of course, I have not done much to chainsaws before so I am trying to get as much as possible figured out before I start. This site and all its members is a great resource for that.
So far all I am going on is the fact that my dad's local dealer said it needs a piston, and that they/he didn't think it would be worth paying for given the age of the saw, so I got it. I can get it running fine but after 5-10 min it seems to lose compression and die. I do not have a compression tester but it does seem kind of weak (picking the saw up by the pull cord it doesn't come all the way out but does unreel a bit). I am also going to check out the oil seals on the crankshaft. Intake boot is good, impulse line from what I can see is good, need to explore that further. Fuel line is new and carb is rebuilt.
I may just need rings, or if the cylinder is shot as well, i'm considering the bolt-on 46mm upgrade. But you are absolutely right, I won't really know til I get in there.
Ok lets back the truck up some...take the muffler off and post up some pics of the piston in various degrees up and down so we can see the crown of the piston and as far down the skirt as possible.
then see if you can borrow a compression tester from a buddy and well go from there.
plenty of willing help here.
So far so good...I think that piston looks fine from here in NJ. I'd be holding off any P/C purchases for now.
lets work up to compression test (since you have the muff off) on that just for elimination of "Ring Stuckage"
Maybe remove the Carb and boot just to get a quickie of the intake side( bearing check more then anything)
the 028's are historical for bad ignitions showing up as anything from moodiness to no spark.
lets work up to compression test (since you have the muff off) on that just for elimination of "Ring Stuckage"
Maybe remove the Carb and boot just to get a quickie of the intake side( bearing check more then anything)
the 028's are historical for bad ignitions showing up as anything from moodiness to no spark.
give it a good blow off first, get the loose crud off. then use a spray detergent- Simple green/purple power next...then maybe a citrus cleaner if there is pine sap.
Indeed, that piston looks good. Some dealers are better than others. Too many times I've heard people say the dealer told them the saw wasn't worth repairing. I'm not sure if they are hoping you'll turn the saw over to them, or they just want to sell you a new saw, or both. My Husky and Stihl dealers by me, all though not extremely knowledgeable of older saw repair, have no problem ordering parts for me if available.
I got the full story from my Dad: the dealer replaced the impulse hose and the condenser. Impulse was cracked. They recommended the intake boot and piston rings as a next step, reported "weak" compression but did not quantify. According to them the saw is "just wore out", and pitched the benefits of a lighter modern saw. Dad has an ms181 which was his backup, now he's just using that for his firewood.
Back to the 028, I Finally got around to cleaning it up a bit. Carburetor off, intake looks good. Fuel line seems very stiff so I'll replace that for sure. (Already has a new fuel filter, air filter, spark plug and carb kit.)
sorry it's upside down. Close up of intake manifold:
Clutch side: very oily in here.
Flywheel side after blowing out tons of crud:
I also noted a lot of crusty carbon buildup inside the exhaust port and on top of the piston. With a new condenser already installed what would the next step be toward diagnosing an ignition problem? (It has spark...)
Back to the 028, I Finally got around to cleaning it up a bit. Carburetor off, intake looks good. Fuel line seems very stiff so I'll replace that for sure. (Already has a new fuel filter, air filter, spark plug and carb kit.)
sorry it's upside down. Close up of intake manifold:Clutch side: very oily in here.
Flywheel side after blowing out tons of crud:
I also noted a lot of crusty carbon buildup inside the exhaust port and on top of the piston. With a new condenser already installed what would the next step be toward diagnosing an ignition problem? (It has spark...)drop a 1/2 of a thimble full of mix down her throat and see if it burps( sounds like it wants to start)
did you borrow a compression tester yet. if there is an autozone( parts store) near you you can rent one for free.
did you borrow a compression tester yet. if there is an autozone( parts store) near you you can rent one for free.
so i got busy with some other projects and the 028 wasn't one of them. After cleaning i reassembled it and fired it up. ran good till it got hot then stalled. i took it to one of two local dealers to ask to test the compression, he listened to it run and said a leakdown test would be what he would do, as the saw seems to lean out at high revs once its warmed up, as if the crankshaft oil seals are sucking air.
He also said given the age and value of the saw it would be a waste of money to hire him to do the work. i guess he's plenty busy! So i ordered a set of seals, got a piston kit while i was at it (really not that expensive) and new rubber parts (fuel line, manifold, etc) and some day when work lets up i will tear this thing apart. thanks to all for the interest and advice thus far!
He also said given the age and value of the saw it would be a waste of money to hire him to do the work. i guess he's plenty busy! So i ordered a set of seals, got a piston kit while i was at it (really not that expensive) and new rubber parts (fuel line, manifold, etc) and some day when work lets up i will tear this thing apart. thanks to all for the interest and advice thus far!
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Any saw shop would have boxes full of burned up 029/Ms290s in back. Buy one of those coils off of them for 5-10 bucks, and slap it on the 028, and be done with that part of it.
sld961
Addicted to ArboristSite
I would not put a cheap Chinese piston in there. You're much better off getting some Caber rings for it, about $15.
Like was mentioned, a coil out of an 029/290/310/390 will convert a points saw to electric ignition. If a coil is bad, it can stop working when it gets hot. You can test this by checking for spark when it gets warmed up and dies.
thanks for the coil tip... will do that, although i am getting spark when hot. it will be nice to be prepared for the eventual points failure. got a golf piston, don't know country of origin, or if i will even need it at this point. i have other saws so this 028 will get rebuilt some day just cause it was Dad's.
towingace
ArboristSite Guru
That's what I had to do, also. Seems some people have done the conversion without any clearance issues.
Also, according to a couple early posters stating that 42mm saws have different rod lengths, is a new one on me! My 028 was originally a 42mm saw. I've ran it for years with a 46mm top-end and the original 42mm bottom end. It was my first saw build and I didn't check squish clearance (didn't even know what that was), but it has run fine all these years. I don't think that would be the case with the wrong rod. By the way, it was worded as a longer rod, not longer stroke. Either way, you would have issues.
I love necroposts. Gotta give RandyMac credit for adding that word to my vocabulary.
I had an 028 that I rebuilt but it just wouldn't run right. I had exhausted all other options except for spark, which it had. Must have been weak cause I put a ms290 coil in it, snipped the wires to the points and that saw ran good after that.
Color me ignant but I never heard of the 1127 coil swap...is there a timing change required or a flywheel swap or a direct plug and play. Man does that make things easy. Anytime you can use an 1127 part it's a good time, they are everywhere...
The saw will run with just the coil swap but not as well as it should from my experience. In most cases it seems the timing if off just a tad on the ones I did and according to what I have read of others doing this swap. I cured my saws by putting on the newer flywheels.
