084 Differences and Info

[Stihl 041S]

Remember though... The rods in a fuel burning hemi are aluminum...

Material doesn't change direction of
force. The alum rods would be"tougher" than the steel ones.
Maybe I'm wrong, but your " hard&tough" is spot on

 

[Stihl 041S]

That's the parts saw.

1. Being built from mostly new parts
2. Complete minus P&C
3. ebay snipe
4. Parts saw, donating it's crank and other small parts to #1[/QUOTE
There's not 1 with an XL cover?

 

[Cut4fun]

Brad I gave a good 84 back half to a guy not to long ago that needed the back part by the exhaust port welded back up where it had broken. I could check with him if he ever used it or not.
There is 2 back halves that my little knowledge knows of, open like in pic and one with 2 tubes inside (which can be cut out).
Also 2 types of covers, one with heat shield, one not.

The backs and covers can still be bought new.
One just sold on ebay new for $60 for back half only. I think (correct me if wrong guys) they are in the $80's through stihl for back only.

 

[Lakeside53]

I'm blown away by the connecting rod on these 084. They look like tooth picks. How in the world do they hold up? I'd seen picks of them, but they look even weaker in person. I guess they work.

They generally do.. but... because of occassional failures, Stihl changed the design (in the 088) to a more conventional approach. It's the torsional vibrations that take out the crank with the thin rod approach. Think "stiffer".

 

[blsnelling]

Brad I gave a good 84 back half to a guy not to long ago that needed the back part by the exhaust port welded back up where it had broken. I could check with him if he ever used it or not.

Sure. I have a MIG welder and could likely fix it up.

There is 2 back halves that my little knowledge knows of, open like in pic and one with 2 tubes inside.

The good saw I got from Steve has the one with the baffling. That would definately have to come out on a ported saw.

 

[Peacock]

Maybe, but Eddie Hill used to bend a set of rods every pass. But that is with fuel, but we don't know about Brad's fourth 084.
Rob

Right. But with a fuel motor they are on the verge on hydro lock the entire pass.

On normal engine rod strength is determined by rpm, not power. At high rpm the crank is literally trying to pull the cap off as it accelerates the piston and rod down the bore.

 

[blsnelling]

I did get a scrap 084 cylinder in a box of parts. Unfortunately, the lining is partially worn away. I don't know if it was from wear, or more likely, a hone. Any chance it would be repairable or worth messing with?

 

[aggiewoodbutchr]

HOLY **** :jawdrop:

Was you WOT in a cut when it happen or milling etc? :help:

Milling..... go figure.:biggrinbounce2:


I hear it all the time but I'm beginning to learn first hand just how rough milling can be on saws.

 

[Stihl 041S]

Peacock;thanks for the info. I was the machinist/electrical guy for a bunch of gearheads that ran alky/feul so I am a little skewed.
Rob

 

[Freakingstang]

I did get a scrap 084 cylinder in a box of parts. Unfortunately, the lining is partially worn away. I don't know if it was from wear, or more likely, a hone. Any chance it would be repairable or worth messing with?

That lining was wore when I got it. It was in a box of parts I got along the way. I did run a hone to it, to see how thin it was......needless to say it is thin. I got one other one a year or so ago that was the same way. It was worn in the sames spots, around the intake and exhaust ports. I'm thiniking the plating must be chrome instead of nikasel. Never seen a 066 wore through like that.

 

[Four Paws]

I did get a scrap 084 cylinder in a box of parts. Unfortunately, the lining is partially worn away. I don't know if it was from wear, or more likely, a hone. Any chance it would be repairable or worth messing with?

Bore it, replate it and make a 140cc saw - then you could be KING of the GTG.

 

[Stihl 041S]

Price of replating and where for pistons?

 

[Four Paws]

Price of replating and where for pistons?

Plating is about $180 and I think includes machining. Pistons could be retro-fit from other saws, or bought from Wiseco. You'd probably want to stroke the crank, too!

 

[Stihl 041S]

Or make your own piston, this is good. Offset grind to stroke or new crank?

 

[Gumnuts]

Bore it, replate it and make a 140cc saw

140cc Interesting.The walls are thick enough to take bore.Sounds fun.
Port for torque only.

What can be done to the crank for strength /durability.Has anyone compared cranks 880 with 84 .Anyone retro-fitted ?
The journals ? The balances ?

 

[brncreeper]

An 880 ported would be OK accept for the limited coil. Can you still order 088 coils?

 

[Gumnuts]

An 880 ported would be OK accept for the limited coil. Can you still order 088 coils?

Plating
Crank
Coil
$$$$$$ It suddenly becoming ,for me,a dream on sticker / but hey ya never know how things pop up in ya life ,do you ?
:rockn:
Would it be called ? MS840Z

 

[blsnelling]

The work has begun. I tore the parts 084 all the way down to bare case halves.

I also stripped the old, broken tank.

As I went, I tranfered parts to the new tank.

I wrote down any parts I need to order. The list of small parts to order is long, but I know excatly what I need now. Most of the stuff is little like screws and buffer cover etc.

It turned out the the bearings were not bad, only dirty from setting. With the crank and seals removed, I was able to clean them where they are now smooth and tight. Never the less, the new case is to have new bearings anyway. The crank is in excellent condition with no signs of heat or any damage to the big end rod bearing.

 

[blsnelling]

At the same time, I began disassembling the complete 084. Having never worked on a 084 before, I needed it to see how everything went together and what parts were needed for the new one.

The saw is in good condition. The only surprise I found was a worn through oil line. No biggie there. I wanted to get this saw apart so that I could clean it properly after having set without a P&C for so long. Once the seals are removed I can ensure that any and all dirt is out of the bearings and will be good to go. I'm still looking for a cylinder for this saw.

These 084s use such a tiny carb. I think I heard them referred to as thumb carbs.:hmm3grin2orange: Well, they're a lot bigger than my thumbs!

A few odds and ends parts.

A couple pieces of orange plastic:biggrinbounce2: A lot of it's not any good.

 

[blsnelling]

Which muffler body does NOT have the baffles? It appears that both of these come with the front cover as well.

1124 140 0605 Muffler USA, CDN, AUS
1124 140 0600 Muffler Standard