Stihl 028 AV Super Rebuild Help...

[mich3210]

Finally got to rebuilding an 028 AV Super that I got from my Father-in-Law.

First time doing this and I've made a few mistakes. Broke a circlip and a fin on the flywheel. All replaceable.

Compression was low, but I'm not sure why. Cylinder doesn't look to be in bad shape. Piston looks like it might be scored a little, but I can't feel them, only see them. What should I do, replace just the piston and rings or piston, rings and cylinder? Where's the best place to get those parts and what are good replacement brands?

I cleaned it up the best I could before I pulled the cylinder, but I know I got some junk in there. What's the best way to clean the crank case without ripping the case apart?

I also found discovered that a few of the annular buffer's were shot. Where's the best place to find all the replacement parts?

Thanks for any help you can provide!

 

[cuinrearview]

That's just a little carbon streaking on the piston. That, and worn rings probably contributed to the low compression. Clean up that piston and cylinder with some light sanding, buy a set of caber rings, and go cut some wood. It would probably be best to replace the fuel line, filter, and impulse line while it's apart. New crank seals wouldn't hurt either. Get your parts from the Stihl dealer.

 

[mich3210]

That's just a little carbon streaking on the piston. That, and worn rings probably contributed to the low compression. Clean up that piston and cylinder with some light sanding, buy a set of caber rings, and go cut some wood. It would probably be best to replace the fuel line, filter, and impulse line while it's apart. New crank seals wouldn't hurt either. Get your parts from the Stihl dealer.

What kind of sand paper and grit? Should I just YouTube how to do this, so I don't use the wrong technique? How do I remove the carbon buildup on the top of the piston, cylinder and ports? Same way, or can I use a cleaner?

Thanks!

 

[cuinrearview]

300-400 grit paper will work for all of it. You can remove the carbon from the dome and ports as well.

 

[grizz55chev]

That's just a little carbon streaking on the piston. That, and worn rings probably contributed to the low compression. Clean up that piston and cylinder with some light sanding, buy a set of caber rings, and go cut some wood. It would probably be best to replace the fuel line, filter, and impulse line while it's apart. New crank seals wouldn't hurt either. Get your parts from the Stihl dealer.

Or on line, that’s where my “ dealer “ gets his.

 

[cuinrearview]

Can you buy OEM parts on-line? I'm aware of a few places but not the full line I thought.

 

[grizz55chev]

Can you buy OEM parts on-line? I'm aware of a few places but not the full line I thought.

I’ve had good luck on evil bay, but you have to shop!

 

[cuinrearview]

Right there's that. I've bought some there but can't always find what I want and sometimes I'm not sure if I'm getting genuine OEM.

 

[grizz55chev]

Baileys is another source of OEM parts.

 

[grizz55chev]

Right there's that. I've bought some there but can't always find what I want and sometimes I'm not sure if I'm getting genuine OEM.

That’s the part where it gets tricky, always look for the words OEM! If it says replaces or OEM part #, it’s probably a knock off.

 

[cuinrearview]

Except for the "OEM" parts from China

 

[grizz55chev]

If it comes in a Stihl bag, it’s oem. Evil bay has burned me more than once, I’m very careful now! My local shop takes at least a week to order parts then I have to take a trip down the hill ( 25 min, one way ) to pick up my order, prepaid of course. When I order on line, they send it to my P.O. box or right to my front door, usually within a few days.

 

[cuinrearview]

As long as you can find everything. For the 036 I'm doing only one or two of the items I need are on the bay. If I have to go to the dealer anyways(mine's pretty convenient) I might as well order everything. It helps to have a rapport with the shops anyways. If they feel like you'll throw them some business buying the parts to rebuild the saw they're more likely to sell you the project saw to begin with.

 

[mich3210]

300-400 grit paper will work for all of it. You can remove the carbon from the dome and ports as well.

Do I need to use sand paper or emory cloth? Do I need to use any kind of oil when doing this sanding? Is there a particular method I should use when sanding the piston and/or cylinder? Looked it up online and some use oil others don't.

Caber Rings are $12. Caber Rings with a Meteor Piston is $34. Should I Just go ahead and replace both for peace of mind, and since I'm in there?

Total to replace the following is between $80 and $100 (all on ebay), depending on if I do the piston or not.
Rings (and possibly Piston)
All 4 Annular Buffers
Fuel Line, Impulse Line and Fuel Filter
Cylinder Gasket
Exhaust Gasket
Air Filter

Seem reasonable?

 

[Bmturner]

028AVS was my first love in a saw. best of luck when you get her running post up some pics

 

[cuinrearview]

Do I need to use sand paper or emory cloth? Do I need to use any kind of oil when doing this sanding? Is there a particular method I should use when sanding the piston and/or cylinder? Looked it up online and some use oil others don't.

Caber Rings are $12. Caber Rings with a Meteor Piston is $34. Should I Just go ahead and replace both for peace of mind, and since I'm in there?

Total to replace the following is between $80 and $100 (all on ebay), depending on if I do the piston or not.
Rings (and possibly Piston)
All 4 Annular Buffers
Fuel Line, Impulse Line and Fuel Filter
Cylinder Gasket
Exhaust Gasket
Air Filter

Seem reasonable?

Sand paper or emory cloth will work. I don't use oil when I sand, just make sure you rinse all of the dust out and blow it off real good with compressed air when finished. Replacement of the piston is completely up to you. Personally I wouldn't replace it if the skirts are not worn for a saw I planned to run. Now that you've been into it any work needed down the line shouldn't be a worry. Your prices for parts seem reasonable.

 

[backhoelover]

Do I need to use sand paper or emory cloth? Do I need to use any kind of oil when doing this sanding? Is there a particular method I should use when sanding the piston and/or cylinder? Looked it up online and some use oil others don't.

Caber Rings are $12. Caber Rings with a Meteor Piston is $34. Should I Just go ahead and replace both for peace of mind, and since I'm in there?

Total to replace the following is between $80 and $100 (all on ebay), depending on if I do the piston or not.
Rings (and possibly Piston)
All 4 Annular Buffers
Fuel Line, Impulse Line and Fuel Filter
Cylinder Gasket
Exhaust Gasket
Air Filter

Seem reasonable?

Don’t forget seal like stated above local bearing shop will have them get skf

 

[backhoelover]

Piston needs replacing the groves that hold oil are wearing away!! That’s from dirt injestion most the time. Also don’t forget to replace air filter

 

[cuinrearview]

Piston needs replacing the groves that hold oil are wearing away!! That’s from dirt injestion most the time. Also don’t forget to replace air filter

I agree with the probable cause of the wear, but with oil in the mix present everywhere inside the engine the "carrying" of oil, like in a four stroke, is not needed here. I wouldn't think twice about cleaning that piston up and expecting years of service from it. If I intended to sell the saw or was repairing it on someone else's dime I would consider replacement, but i don't think it's needed.

 

[mich3210]

Don’t forget seal like stated above local bearing shop will have them get skf

Do I need to crack the case to replace those seals?