Stihl 028 AV Super repair

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The clutch will be a bear to get off, it takes big torque to break them free but it will come off, use a longer breaker bar or extend a shorter one with a length of steel pipe. I have used an air powered impact gun on really stubborn ones but there is a risk of breaking the spider arms off if the springs and shoes are not pulled off the carrier first.
 
The clutch will be a bear to get off, it takes big torque to break them free but it will come off, use a longer breaker bar or extend a shorter one with a length of steel pipe. I have used an air powered impact gun on really stubborn ones but there is a risk of breaking the spider arms off if the springs and shoes are not pulled off the carrier first.
I added pics. It looks near impossible to get those springs and shoes out...
 
So i'd take out the rope, install the plug, and then try the impact?

Careful there, I broke more than one clutch doing this, it works fine on the flywheel nuts but the clutch shoes are separate heavy weight pieces and the sudden snap of an impact can and has broken the arms off the center carrier, maybe my Ingersol Rand has a bit too much snap to it...:)
 
I added pics. It looks near impossible to get those springs and shoes out...

Maybe try a lighter duty battery impact gun that may do it but after breaking a couple clutch carriers I just went back to breaking them free with a longer breaker bar, 1/2" drive 24" Snap On breaker, it has removed clutches from every make and model saw for me. On really tough ones I mount the bar to the studs, use a stack of big washers and the bar nuts to hold it in place, then clamp the bar in my bench vise, that will keep the powerhead steady and I can apply plenty of force to the breaker bar.
 
Agreed. I’ve busted two shoes using a pneumatic impact with a quick trigger lol. Old, worn clutches ...but still not fun.

I always try the breaker bar first. A little shot of LetGo or WD could help, but it’s usually force that gets these old clutches off.
The battery impact against compression should work if you can’t get the breaker bar to do it.
 
Maybe try a lighter duty battery impact gun that may do it but after breaking a couple clutch carriers I just went back to breaking them free with a longer breaker bar, 1/2" drive 24" Snap On breaker, it has removed clutches from every make and model saw for me. On really tough ones I mount the bar to the studs, use a stack of big washers and the bar nuts to hold it in place, then clamp the bar in my bench vise, that will keep the powerhead steady and I can apply plenty of force to the breaker bar.
I will try it that way first, thanks!
 
I did a pressure test first. It wont hold pressure or vacuum. the clutch is off, and the nut off the flywheel. Ill look into alternative methods of getting the flywheel off since i dont have that tool.
 

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Lift the saw up by holding the flywheel, smack the center of the crank with a brass or aluminum hammer or drift , it will usually pop off. Be real careful if driving screwdrivers, chisels etc under the flywheel as I have seen some serious damage done that way, best to use a couple of nylon felling wedges if going that route. The proper tool is the best way, they are cheap off the bay, the AM ones work well enough and can be found for under $20.
 
It’s probably gonna be the flywheel side seal. That’s what usually goes on these saws.

Make sure you take some pics and/or measurements before you take the seal out. You need to know the depth. It’s easiest to get out by pushing one side in with a punch, the other side will be more accessible to grab with a pic.

Invest in a puller, they are cheap. If you can’t wait, use a wood wedge between the flywheel and saw body. Be gentle, you don’t need a ton of pressure. After wedge is installed, heat flywheel around crank with a propane torch, wear gloves, then put a punch in the flywheel center and give the punch a good whack or two. It will pop right off.

This is the method I use on saws where there isn’t a puller always available, like some solo and Husky’s. Husky even has a tool called a “crank knocker” that allows one to install over the threads to protect them, making it a one man operation without the wedge.
 
I got the flywheel off. Plugged everything and it was leaking. Got soapy water and the connections on the hose and where i closed off the carb and exhaust were leaking also. Put some small zips on the connectors and some rubber roofing on the carb etc. No leaks now. Pumped it to 10psi it held there until i released it, over a minute. Did the same for 10"vac, and it held. Nothing is leaking.... im assuming the carb is the next culprit to check?
P.s. i did loosen the spark plug after 2 min. Just to make sure the connections hadnt collapsed. As soon as it was loose pres. Started dropping. I did video the tests but it takes a long time to upload.
 

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Did our rotate the crank while under vacuum? If you’re still setup, I’d try that as well.

It could still leak hot and not at room temp. Less likely but still possible.

Yes, the fuel system would be next.
I will try and rotate it, im still set up. It does the same before its warmed up so i dont think thats an issue.
P.s. i just checked it to spin the crank. I pumped it up last night to 10psi and it was at 9.5 this morning. I turned crank for about a minute, gauge never dropped. It did go up and down about .5psi as piston moved, but no loss.
 
Looks like your getting er done.

I must say I have to admire the way you got that clutch off by using that chain bar to get some leverage on the clutch. I ran into an 028 once that I couldn't get the clutch off by myself because either the saw would move and the breaker bar and socket kept slipping off the clutch while trying to hold the saw . I had to get my son to help me by literally putting one foot on top of the cylinder and the other foot in the rear handle while I used the breaker bar and socket to keep it straight so I could finally get a good bite on the clutch to break it free. I still couldn't believe how much torque it took with a long breaker bar to break that clutch free for such a small saw . Loosing lug nuts on a tire was easier than that stubborn 028.
 
Looks like your getting er done.

I must say I have to admire the way you got that clutch off by using that chain bar to get some leverage on the clutch. I ran into an 028 once that I couldn't get the clutch off by myself because either the saw would move and the breaker bar and socket kept slipping off the clutch while trying to hold the saw . I had to get my son to help me by literally putting one foot on top of the cylinder and the other foot in the rear handle while I used the breaker bar and socket to keep it straight so I could finally get a good bite on the clutch to break it free. I still couldn't believe how much torque it took with a long breaker bar to break that clutch free for such a small saw . Loosing lug nuts on a tire was easier than that stubborn 028.
Pioneerguy600 gave me the info on how to do that. My workbench, which i made, is set up to hold stuff while i work on it. Those holdfasts are great for this kind of work. Just like having a helper that doesnt complain. Heres a pic right after i finished building it. I hadnt drilled the holes for the holdfasts yet.
 

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Pioneerguy600 gave me the info on how to do that. My workbench, which i made, is set up to hold stuff while i work on it. Those holdfasts are great for this kind of work. Just like having a helper that doesnt complain. Heres a pic right after i finished building it. I hadnt drilled the holes for the holdfasts yet.

Very nice bench there, a vice becomes an necessary item for a mechanic.
 
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