Assembling the NOS 084

[Gumnuts]

Just nutting it out !!!!

What's the story on internal and external seals.
Is this applicable for the 84 ? My new case came with bearings insalled. Read a thread on seals that promotes internal placement.External seating
will not be as good on pressure test.Understand the
principle .Sounds like either way OK as long as dirko ( or loc 680) outer rim
and white grease inner dust seal rim.

My repair book only refers to external instalation.

Andy or whoever if internal applicable can you tell me the steps .Using an arbor.
123..>/
Internally fitted seals - do they just fit against the bearing step form the inside ?

:greenchainsaw:

 

[Lakeside53]

Wow - now those seals look shot( under-statement).If it came out that easy will you need to find a bigger outer diameter bearing ,as the journals are worn OR bog a new one with loctite ?

The bearing is custom, so no oversize available. In any case, it's only about 1-2 thou wear, which is like an elephant in bearing fits.

My preference - get another case.

Options (ebay sale product):

- manually "dimple" the inner case surface, then red loctite the bearing in.
or
- find a retired machinest with more time on his hands than he knows what to do with.. and sleeve then grind out for a heavy bearing fit... pita... at best.


I'm not sure what the owner will do. He left with large box of parts.

 

[Lakeside53]

What's the story on internal and external seals.
Is this applicable for the 84 ? My new case came with bearings insalled. Read a thread on seals that promotes internal placement.External seating
will not be as good on pressure test.Understand the
principle .Sounds like either way OK as long as dirko ( or loc 680) outer rim
and white grease inner dust seal rim.

My repair book only refers to external instalation.

Andy or whoever if internal applicable can you tell me the steps .Using an arbor.
123..>/
Internally fitted seals - do they just fit against the bearing step form the inside ?

:greenchainsaw:

On a case with mag journals, just heat it to 300F and drop the bearing in. If the case is sleeved with STEEL ring (clutch side - most Pro stihls), heat case, then insert bearing with the press - guide the bearing with an arbor made such that the pressing is ONLY on the outer race. Case must be perfectly in place with the press and bearng, so it's easier to press from the outside in, then flip over and adjust back to the oil pump or stop. I showed pics of this in the 066 case split thread.. I think...


yes... seals can fit inside the bearing. Stops the problem of the case expanding and the seal popping out.



There is NO issue with pressure test... very tight fits..

 

[Gumnuts]

I'll warn you of this. If you choose to remove a cage on a new bearing, the bearing is so tight that the balls are not easy to realign. I got it done though.

Was wondering about that.
hmmm....maybe i think to much .Just looking at the pros and cons hmm....
thanks guys.

Would'nt heating it in foil covered container help prevent burn or bubble, if one does'nt have convection oven.

 

[Gumnuts]

On a case with mag journals, just heat it to 300F and drop the bearing in. If the case is sleeved with STEEL ring (clutch side - most Pro stihls), heat case, then insert bearing with the press - guide the bearing with an arbor made such that the pressing is ONLY on the outer race. Case must be perfectly in place with the press and bearng, so it's easier to press from the outside in, then flip over and adjust back to the oil pump or stop. I showed pics of this in the 066 case split thread.. I think...


yes... seals can fit inside the bearing. Stops the problem of the case expanding and the seal popping out.



There is NO issue with pressure test... very tight fits..

thanks Guys

 

[Lakeside53]

Why this is my wife's kitchen oven of course So it's radiant. Same place I found that handy dishwasher, which I need to throw a couple things in. This wasn't the first time I saw this happen. I just wasn't sure of it. Now I am. This is what ever Stihl's factory finish is.

I'm working on editing the pictures so show the beginning of my assembly process.

That's you problem... spot temperatures in a radiant oven can be MANY times the air temp... especially if the item is exposed to the heating elements. Radiant temperature control is AVERAGE - adjusts the duty cycle max on and off. A convection just heats the air... much nicer.. and safer. You'd be better off with my cardbord box shade-tree convection oven.


Some suggest covering the item with foil. I say don't - just use convection...

The black plastic retainer in the bearings would have been very unhappy in a radiant environment..

 

[Gumnuts]

He left with large box of parts.

NOW THAT CRACKS ME UP - I CAN SEE HIM SCRATCHING HIS, SOON TO BE BALD SPOT. PLUS A GIGGLE OR 2

 

[bcorradi]

Works on some of the larger seals.. Real hard on the likes of the flywheel side of and 026.. almost impossible sometimes..

I can second this...I spent quite a bit of time yesterday pulling off the flywheel seal on an 024 .

 

[Lakeside53]

It was an 024 that finally made me break down and get the right tool! The 044 and 064 aren't much better.

 

[blsnelling]

Hey Gumnuts. Ever seen this tie before? I had my wife shoot this after I spent the evening in the garage working on the 084.

 

[Gumnuts]

thanks for the pic - looking out for the Sunday one

Hey Gumnuts. Ever seen this tie before? I had my wife shoot this after I spent the evening in the garage working on the 084.

I'll have to show the wife / Sandy, when she gets in.She'll get a buzz.


NOW WHAT SHIRT WILL I WEAR....HMM....


( thanks for the OTT wrap )

 

[blsnelling]

I thought I'd show some of the steps in assembling this saw. These are all from tonight.

Before I got too far, I though I'd take a pic of my new parts collection.

Here are the case halves already together. Enought about that dead horse. Torque the case bolts to 102 in/lbs. This shot was taken out of sequence as you can tell by the oil seal already being installed.

Dribble some straight 2-stroke oil on the bearings.

Place a coat of oil on the seal lips themselves.

Here I'm installing the oil seal. It's very important to stay on the outer edge of the seal. Otherwise you will bend and distort the metal, possibly causing the seal to fail. It's also very important to make sure you do not roll the back side of the seal and cause the spring to come off. I do this by "wollering" the seal lip around the crank until it just slips over it.

The reflective foil has been applied. This is not as care free as you might think if you want it nice and straight and fitted to the curves of the case.

Here's something I'd never run into before tonight. The flywheel I bought is seriously cracked. If not caught, this would have likely led to a catastrophic failure. Lukily, I had another in the spare parts pile.

As you can see, it comes from the keyway.

 

[blsnelling]

Here's the nice, freshly cleaned up spare flywheel installed.

Looks to me like it's time for a P&C. A couple things here not pictured. Oil the needle bearing well before installation. Also lube the wrist pin. Install the piston so that the arrow on top is pointing towards the exhaust side. Place a towel over the case opening before installing the circlip. OK, I didn't. MAKE SURE THE CIRCLIP DOESN'T BEND AND IS PROPERLY IN PLACE!!! It's hard to swallow $350 for a new P&C over such a simple mistake. Double check you work. Also take care to put the end gap of the circlip at 12:00 or 6:00. Finally, put a coat of oil in the installed piston walls, including the rings.

Put a coat of oil on the cylinder wall.

The piston stop and ring compressors can be gotten by without but are only a few bucks from Baileys.

While holding the ring compressor, slide the cylinder straight down onto the piston. Do not twist it back and forth. You may catch the end of a ring.

Tighten it down in a criss-cross pattern. Torque to 132 in/lbs.

Install the decompression valve.

Don't forget this little screw/plug. It'll put a hole in your plastic if you do. Trust me on this one. I know.

 

[blsnelling]

Now here's something I'll likely catch some flack over, but that's OK. Won't be the first time. I like to put high-temp RTV on the muffler gasket to help make sure there are no leaks. I've got a clean saw here and don't want oil running down the cylinder onto the case where I can't get to it to clean it off easily. I've done this on V-8 headers as well. I've even done this to seal muffler covers on my saws.

I had a clearance issue here. No, it doesn't matter that Stihl wants your first born to buy one of these things. Didn't stop me from take a carful hammer to it thought.

And here's how I left it for the night.

 

[blsnelling]

Just a little disclaimer here. I only this week got my first specialty Stihl tool, a flywheel puller. Go figure, it doesn't even fit the 084 But it fits most others. Everything I do is with common hand tools, 25 years of watching Dad and learning on my own, a little patience(sometimes), and a little luck. I can't leave out the knowledge that has come from you guys here at AS. There may be some that frown at some of my methods, maybe not. But the moral of the story is this. You can do this stuff too!! Take pictures and ask questions. The first saw I ever took apart was a 026 I bought here less than 1 1/2 years ago. I love tinkering with these things and get a lot of enjoyment out of it. I hope someone benefits from something here.

 

[Scandy14]

Brad,

Great post, and pictures. Very good step by step instructions. Thanks for taking the time to share.

 

[blsnelling]

Brad,

Great post, and pictures. Very good step by step instructions. Thanks for taking the time to share.

I think it's all part of the disease. I'm normally a very driven person and wouldn't want to slow down to take pictures. What I'm figuring out, is that this addiction is not just to saws, but to AS. So I have to take the time for the pictures so that I have them to post on the forum here

 

[brncreeper]

Was there a gasket between the cylinder and case? Great reference post, terrible tie! Just kidding.

 

[blsnelling]

Was there a gasket between the cylinder and case? Great reference post, terrible tie! Just kidding.

Yes there was. I failed to mention it. This saw is being built bone-stock. It'll likely not be staying that way for long though

 

[parrisw]

Great post!!! reped ya some. One day I will pick up a fixer upper. I just did a small fixer upper, but didn't need allot, 272xp.