028 av super rubuild

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Wandering ami

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Pardon me if i ramble a bit.

I'm a city guy just moved into an off the grid cabin tucked away in the app. mtns. Picked up my first chainsaw this year from a friend. A ms170. Pulled the carburator and replaced it and off I went.

Well, my next door neighbor (well next valley over) is a little, old lady in her sixties who's lived in these mountains all her life, hired me to come over and help her on her farm. Her and her kin are from a long line of homesteaders and sharecroppers.

She say something like, "that house over there was where me and my sister grew up. The Alexs built it in 1908 and my daddy bought it from them in 1930 or 1940..."

Real sweet old lady. Pays me fair from what she gets selling jams and jelly and always throws in a bit of food. I, of course, try to give her a few extra hours of work to her chargin.

"Well, we should stop today. You're done plucker out. What? Yeah, I need that firewood moved, but you don't worry about it. What? Yes the sheep need shearing, but I can do that later. And I guess that culvert is clogged, but don't you worry about it..."

Anyways, she's got relatives around her but her husband and only son died some time ago. So a lot of her old equipment has gone to rust. In a pile of rust, I found an old 028 av super!

"What? That old saw? Why my husband and daddy went in together for it about 30 years ago. It work great till it died on me. I got that new one now..."

I convinced her to let me take a look at it. Thus far I've taken it partially apart, but since I hanvt done much engine work before, I'm just scratching my head. I'm commit to trying to get it to start again, if only for the experience and to make my neighbor happy.

I'll say ahead of time. Shortly after her husband died or after her son died, the saw was used hard with little care. My guess is there's a lot of damage.

I've figured this far I need to replace the ignition system, the carb, and all the gaskets and rubber bits. I don't have the right screw driver to get to the piston or the right tools to pull the fly wheel. The piston looks clean from both ports, and it's getting really good compression.





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I'm in the sun right now, working it over with some simple green, a tooth brush, and a blower. Trying not to drive dirt any deeper into the guts, but it's a bit too late for that.

Where can I even get oem parts for this thing? I'm not a big fan of knock off parts. I learned that the hard way with my ms170, which worked great but then slowly developed "ghost" problems because of a knockoff carburator.
 
After way to much driving, I've picked up a carb kit, filters, and gaskets. Everything but the coil which apparently is over 120 bucks. Well, I've gotten a knock off from Amazon for 12 bucks.

The price for everything has been 120. If I was willing to buy knockoffs, it probably would have been half that. Well, in my mind it's still a good deal. Still cheaper then buying a new saw of equivalent power.

I spent a morning cleaning the insides. I'm ready to start putting it back together!
 

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I just redid mine, to wash my advise is a 5 gallon bucket with degreaser, let it sit overnight, then brush off and pressure wash. let dry reassemble.
 
I just redid mine, to wash my advise is a 5 gallon bucket with degreaser, let it sit overnight, then brush off and pressure wash. let dry reassemble.

Pressure washer will put water where it's not supposed to be. You need to do complete take down ASP or water damage.

Degreaser works, but diesel is cheaper, (works better too) and a parts brush. I use a large tote/recycle carton to wash/catch the offal. Put that splooge in a recycle. Then detergent or simple green. Then start taking it apart........... X2 when you get the clutch/flywheel off......
 
I don't understand your comment, In my case engine was emoved/ disasseble in the first place. In canada, degreaser is cheaper beacause it is 1:16 parts/water
 
Well damn, mad professor. You got me there.

I got home, put in all the new parts, ordered me a new knockoff coil. It was going to take 2 weeks for the coil to get here. I was disappointed cause I wanted to start the saw now. .

Went to sleep, and at about 12 am, had the thought of "Well, you never tested that coil when the saw was clean..."

Jumped out of bed, slapped that sucker back in, and after a dozen cranks, got 028 to fire up. I'm sure my neighbors were real happy for me.

Saw runs fine thus far. It starts up one in crank, often without needing to choke it.

Problem is that someone has reamed all the carb adjuster screws to ****. So at this point, I know the saw starts and runs fine, but I can't tune the carb properly. Going to go to the sthil dealer this week to get replacement screws and a few other gaskets I forgot about.

I don't have a tachometer to set the high screw. Might either order one or walk into an auto parts store and see if they have one to rent.

Other then all of that, the piston has some damage to the one side of the exhaust port. Not enough to effect compression, but it's something to keep an eye on. Supposedly it's caused by a user error, but I can't remember what. Maybe a cold start?
 

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Well damn, mad professor. You got me there.

I got home, put in all the new parts, ordered me a new knockoff coil. It was going to take 2 weeks for the coil to get here. I was disappointed cause I wanted to start the saw now. .

Went to sleep, and at about 12 am, had the thought of "Well, you never tested that coil when the saw was clean..."

Jumped out of bed, slapped that sucker back in, and after a dozen cranks, got 028 to fire up. I'm sure my neighbors were real happy for me.

Saw runs fine thus far. It starts up one in crank, often without needing to choke it.

Problem is that someone has reamed all the carb adjuster screws to ****. So at this point, I know the saw starts and runs fine, but I can't tune the carb properly. Going to go to the sthil dealer this week to get replacement screws and a few other gaskets I forgot about.

I don't have a tachometer to set the high screw. Might either order one or walk into an auto parts store and see if they have one to rent.

Other then all of that, the piston has some damage to the one side of the exhaust port. Not enough to effect compression, but it's something to keep an eye on. Supposedly it's caused by a user error, but I can't remember what. Maybe a cold start?

Are the screws for the carb, screwed, where the driver fits in? If so might be able to cut the slots deeper with a cutoff wheel on a dremel.

You can set carb without a tach. Need sharp chain, clean air filter , and a bar length round of wood. You tune in the cut. Lots of posts/threads on this.

I've never owned a saw tach and have been tuning my saws , since my Dad gave me a Homelite. Never scored a piston yet,
 
Are the screws for the carb, screwed, where the driver fits in? If so might be able to cut the slots deeper with a cutoff wheel on a dremel.

You can set carb without a tach. Need sharp chain, clean air filter , and a bar length round of wood. You tune in the cut. Lots of posts/threads on this.

I've never owned a saw tach and have been tuning my saws , since my Dad gave me a Homelite. Never scored a piston yet,

After reading this, I went back and double checked my mental notes. Turns out, you're right again. The carb screws were fine, I had mis read the book. Well that's what happens when you're teaching yourself and reading a 200 page repair manaul at 11 pm at night.

I threw the screws back into the carb, adjusted the way people said you should and the saw fired right up and started cutting without issue. So damn, the saw is almost done. Just need a piston head gasket.

The next morning my neighbor came by and politely ask "can we not cut wood at 10 pm at night...".

Well... That's a fair point.
 
After reading this, I went back and double checked my mental notes. Turns out, you're right again. The carb screws were fine, I had mis read the book. Well that's what happens when you're teaching yourself and reading a 200 page repair manaul at 11 pm at night.

I threw the screws back into the carb, adjusted the way people said you should and the saw fired right up and started cutting without issue. So damn, the saw is almost done. Just need a piston head gasket.

The next morning my neighbor came by and politely ask "can we not cut wood at 10 pm at night...".

Well... That's a fair point.

Read up on carb tuning, lots of info here. Factory settings are good to start with if everything else is in order. You can do it without a tach but must be careful not to lean out HI screw. Better a little rich than lean. Sort out piston smear first.

Post a picture of your piston. If there is transfer smear inside the cylinder that should be cleaned up or it will cause more damage, don't run it until you check. Might consider a $40 Meteor piston/rings?

If you are going to replace the base gasket get a set of rings at least, cabers will set you back ~$10. See remarks on piston condition and aluminum transfer. If you have an OEM gasket set you have seals too, might want to do those now while saw is cleaned up.

You will like the 028S, a bit heavy but built like a tank just like the 038. My 028S was my first Stihl, I still have it and it runs fine. These days I usually grab my 036 as it's about same weight but more power. But the 028S has been as reliable as the sun.
 
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