Given Stihl 028 AV

[hillbillycycles]

Hello all. I've been reading here for a couple of days and joined up so I could hopefully get information I could not find in my search of the forum.

I recently was given a Stihl 028 AV Wood Boss chainsaw in pretty good condition. My father in law gave me the saw because he said it needed a clutch and/or sprocket. The symptom he described was when he would tighten the chain after a few minutes of running the chain would be so tight it would bog the saw. When I received the saw the sprocket cover, bar, and chain had been removed. I was happy to see only those parts removed as I dislike getting a box of parts and then try to make something of them.

Upon inspection the sprocket does look worn, but this is my first chainsaw to work on so I don't have a good frame of reference. Inspection of the bar told me it was a 16" Stihl bar. However, I noticed a few things I thought were not normal. First, there was a definite wear spot on the top of the bar right before the sprocket on the end. Also, the bar has been hot enough in a few spots to have the steel change to the tell tale blue color.

I have not attempted to start the saw as of yet because I plan on doing the following:
1. Clean and inspect the carburetor
2. Check to see if the saw is electronic or point type ignition and tune if point type.
3. Replace fuel filter and all fuel/vent lines.
4. Pull/clean muffler and inspect through port.
5. Replace spark plug

Also, how do you guys normally clean your saw before you work on them?

Just as an aside, this may be my first saw to work on, but I’m not shy with tools. I perform all kinds of auto maintenance, work on motorcycles and atvs, and have totally restored one old two stroke dirt bike. I think I possess the ability, but not the working knowledge around chainsaws.

Thanks in advance for any and all help.

 

[TimberPig]

Sounds like you have a pretty good handle on what needs to be done.

By the sounds of it, a new sprocket, bar and chain are in order for that saw. It sounds like the current ones are worn out.

As to what to clean it with, try this thread, it was recently discussed quite thoroughly.

Cleaning saws

And welcome to the forum.

 

[hillbillycycles]

Thanks, TimberPig.

I read the thread on cleaning and that was pretty much what I was going to follow. Rubber plugs in all the important holes and Simple Green or Super Clean to cut the crud followed by liberal application of compressed air.

Is there a way to check the chain oiler pump besides just running the saw?

I was pretty lucky in that there were four new chains in the box with the saw. There are two old, loose chains in there too, but I plan on tossing them because I don't know their history.

I'll probably be back as I get further into this little project.

 

[TimberPig]

Short of completely disassembling the oiler and checking all parts for wear, or something similar, the easiest way to check the oiler is to get it running, but with the bar and sprocket cover off, and see if oil is being pumped. If it squirts a good stream, the oiler is fine, if it barely dribbles or does not pump at all, something is likely clogged up. In thats case, start by enduring the oil tank and the associated filter and oil line to the oil pump are all good and clean. If they aren't the issue, you'll have to pull the oiler.

If you need it, thompson1600 here on the site has a website with the IPL and shop manual available on it for download.

 

[buck futter]

I say keep those old chains they don't take up much room but if you ever want a chain for demo work throw the old chain on it couldn't hurt anything as far as wear if you use it for only a tank or two of gas. If they get beat you don't have to worry about it toss them at that time.


Lucky

 

[hillbillycycles]

Thanks guys. I got the saw cleaned up last night and managed to get the sprocket off. Measuring the depth of wear the sprocket is beyond worn out. The average depth on the wear pattern is around 0.043" and I remember reading that 0.020" was considered worn out.

I also pulled the exhaust and looked at the section of piston/rings I could see and they look fine. Pulled the spark plug and was encouraged to see that it appears the last time the saw was running it was running about right on the lean/rich scale.

However, I did run into one thing around the fuel filter. How in the world do you change this thing? Well, more importantly, I could see it in the tank so I reached in through the fuel filler hole with a pair of forceps and the fuel line broke off at the top of the filter right away. Not a big deal since I was planning on replacing all the lines, but how in the world would you replace the filter if you weren't replacing the lines? It didn't appear to me there was enough line to get the filter clear of the tank.

Thanks again. I really enjoy working on stuff like this. Well, on the workbench at home. I do not enjoy working on stuff in the field when it should be running.

 

[Lakeside53]

A new hose will JUST stretch enough to allow you to put the filter on. If it bothers you, put the filter on first and gently ease it in though the tank first.

Check your AV mounts. If the fuel line is shot, often the mounts are also gone on the older saws. I just replaced just about everything rubber on an 028.

 

[BIG JAKE]

A new hose will JUST stretch enough to allow you to put the filter on. If it bothers you, put the filter on first and gently ease it in though the tank first.

Check your AV mounts. If the fuel line is shot, often the mounts are also gone on the older saws. I just replaced just about everything rubber on an 028.

Andy is there a source for new iso mounts for these saws or are you robbing the bone pile/tailoring?

 

[Lakeside53]

Andy is there a source for new iso mounts for these saws or are you robbing the bone pile/tailoring?

They are all available new from Stihl... I replace them all the time as the disk on the end separates from the rubber after about 20 years.

 

[Diesel JD]

I would buy a rim and drum system from Baileys for replacing the sprocket. That way you'll only be out $3.95 next time it needs replacement which is about after 2 chains are worn through. Too easy not to do. For the bar I would either get a Stihl ES bar(replaceable nose) or go witha n oregon power amtch. the laminated bars both oregon and stihl wear too fast for my liking. I would run a 18" .325" pitch. You might want to use Stihl 26RM2 safety chain or Oregon 35SL since this is your first saw until you get the hang of it. make sure the chain brake works well and be careful,
J.D.

 

[Lakeside53]

I would buy a rim and drum system from Baileys for replacing the sprocket. That way you'll only be out $3.95 next time it needs replacement which is about after 2 chains are worn through. Too easy not to do. For the bar I would either get a Stihl ES bar(replaceable nose) or go witha n oregon power amtch. the laminated bars both oregon and stihl wear too fast for my liking. I would run a 18" .325" pitch. You might want to use Stihl 26RM2 safety chain or Oregon 35SL since this is your first saw until you get the hang of it. make sure the chain brake works well and be careful,
J.D.

You really wear out a sprocket every two chains? WOW, what are you cutting with, barbed wire instead of a chain? But yes, the rim system is much better than sprockets, and cost effective over time.

 

[Diesel JD]

No Andy...no I don't but I was just going by the info Stihl gives you. I think they are basing it on running the chain a lot longer than any serious user would run it...as far is a lot more worn out.

 

[Lakeside53]

No Andy...no I don't but I was just going by the info Stihl gives you. I think they are basing it on running the chain a lot longer than any serious user would run it...as far is a lot more worn out.

Just checking I have no idea where Stihl comes up with that number, and, neither does anyone at Stihl I ask about it!

They also say 0.5mm, or .020 inch wear and you should replace the sprocket or rim. I think that's a much more reasonable guide, but most don't change it even at that.

 

[Diesel JD]

Andy how would you go about measuring the wear(other than just by eyeballing it...experience)? I could get creative but there's gotta be a right way.
J.D.

 

[Lakeside53]

Andy how would you go about measuring the wear(other than just by eyeballing it...experience)? I could get creative but there's gotta be a right way.
J.D.

I eyeball it, but compare to a known gap. In particular, if the wear is more than a newspark plug gap (0.5mm), it's getting beyond spec... Hold a plug near it..

 

[hillbillycycles]

Thanks everyone for your input. I've gotten the saw torn down and cleaned up. I ordered a new sprocket and bar from my local Stihl dealer last Friday. I did not get the rim sprocket conversion kit, but I might next time around. Most likely this saw will be used to cut a few cords of wood each winter and clean up a little around the farm, but not much more than that.

I've got the carb pulled off the saw, but have yet to inspect and clean it. I'll get to that later this week.

By the way, I measured the wear on my old sprocket using a set of digital calipers. When you open them up there is a little metal bar that sticks out the end for measuring depth.