028 av super rubuild

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I have 4 (or maybe 5) 028's in the garage, in various states of disrepair. Really, I think the worst of it is "needs carbs and replacement caps". I've been planning on getting another used Poulan to replace my 4218 (which I used as a limb saw, with a 14" bar). I could use an 028 for that, but I seem to recall it's quite a bit heavier than the Poulan, and power isn't really an issue for a limb saw. The light weight of the Poulan made it great. I have the Echo 501 and 620 for the bigger stuff.
 
I've read somewhere the damage could from running the saw lean?

That's not too bad. It would polish out with a scotch brite pad. How does cylinder look?

The clutch side of cylinder runs hotter. As that saw was filthy, it may just be due to overheating. Do a pressure/vac test anyway.

If you reuse the piston, check clearance at the skirt to see if it's worn. You can get a rough idea with feeler gauges. ~0.0025-0.003" is new.
 
That's not too bad. It would polish out with a scotch brite pad. How does cylinder look?

The clutch side of cylinder runs hotter. As that saw was filthy, it may just be due to overheating. Do a pressure/vac test anyway.

If you reuse the piston, check clearance at the skirt to see if it's worn. You can get a rough idea with feeler gauges. ~0.0025-0.003" is new.

I'm probably going to reuse the piston and rings. The cost of the rebuild is starting to get a bit more then I'm comfortable with. Compression seems to be good, and I'll compression test it after I get the cylinder gasket. Is that different from a pressure vac test? And if so what to would I use.
 
I got it working well, but I ended up replacing the piston gasket and trying to tweak the carb meter, but unfornuately I've messed something up.


It only starts with the trigger pressed down, and runs at full speed, but dies instantly once the trigger gets released. Been trying to adjust the low idle screw, but that doesn't seem to do anything.

What did I do wrong?
 
I got it working well, but I ended up replacing the piston gasket and trying to tweak the carb meter, but unfornuately I've messed something up.


It only starts with the trigger pressed down, and runs at full speed, but dies instantly once the trigger gets released. Been trying to adjust the low idle screw, but that doesn't seem to do anything.

What did I do wrong?
Turn the L & H screws clockwise until they are lightly seated and then open each one 1 full turn.

Now turn the LA screw clockwise until the point contacts the arm on the throttle shaft and then another 2-3 turns clockwise. Saw should run at idle at this point. If it idles too fast turn the LA screw CCW to set the correct idle speed. if it still won't idle you have you have another problem.
 
Turn the L & H screws clockwise until they are lightly seated and then open each one 1 full turn.

Now turn the LA screw clockwise until the point contacts the arm on the throttle shaft and then another 2-3 turns clockwise. Saw should run at idle at this point. If it idles too fast turn the LA screw CCW to set the correct idle speed. if it still won't idle you have you have another problem.

I'll try this again. I had it tuned properly before I took it apart to replace the piston gasket.
 
My guess is if that doesnt' work, I've ****ed up setting the metering lever on the carb.
Why not reuse the old metering lever? It was likely already set correctly. They don't wear out unless you happen to drop it on the garage floor and step on it!

You may also have created an air leak when you messed with the cylinder. This will burn up the saw if run under load and could cause idle issues depending on the severity of the leak.
 
Why not reuse the old metering lever? It was likely already set correctly. They don't wear out unless you happen to drop it on the garage floor and step on it!

You may also have created an air leak when you messed with the cylinder. This will burn up the saw if run under load and could cause idle issues depending on the severity of the leak.
I threw the old one back in now. I think I left out a part behind the carb that creates a proper seal.
 
the 028 AV Super is a great do-most saw. I have one from the 80's also, inherited. When I first got it in the early 2000's, the bar seemed original as it still said "Made in West Germany" on it... awesome.

Worth keeping, good job. A trained ear can tell when it's running at full song, full tilt boogie, and not too rich or lean. It might smoke and coke up the muffler if it's too rich.

Mine always used to move the chain a little bit when it was set to idle, just a touch. If I set it to where it wouldn't move the chain, it would die often when sitting by itself idling. I probably had/have an air leak somewhere. The electronic ignition on the 028 AV Super is good,

Mine is currently at a shop getting looked at, it would run erratically last week and die when turned sideways to make long felling cuts. Also leaking bar oil a lot. It had only been used twice in 2 years until last week. Hopefully the piston/jug is good, even if it's not I'm definitely fixing it. Mine has an 18" bar and 325 chain on it, when it's sharp, it rips... but I just got a rebuilt 038 AV Super w/ 20" bigger 3/8 chain to tackle a lot of big oaks.

Keep going!!
 
Hah! Just finished this rebuild. It starts up with a single crank and runs perfectly!

The total damage was:
a really deep clean of guts. (Hours of scrubbing)
Replacing all gaskets (15 bucks for gasket material and sealer)
Rebuilding carburator (15 bucks for kit)
Cleaning and scrubbing down the piston.
Replacing air filter (40 bucks)
Replacing gas filter (5)
Replacing spark plug (5)
Replace clutch bearing (10)
Replacing carburator seal ring (6)
Carb cleaner, random tools, testers (who knows?)
Total cost was around $130 using oem parts.if I included the tools, it's a whole lot more.

Can't wait to give it back to my neighbor. She's going to be happy to have a tool back that been in her family for 30 years.
 

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