Stihl 066 Crank size question

[uziduzit9mm]

Hi, Im rebuilding a Stihl 066, that was given to me. Unfortunately I do not know the story behind this saw. All parts appear to be original factory Stihl tho. Anyways, Its a complete rebuild with new bearings/seals. So far, I've assembled the crank case with the new pressed in Stihl bearings, and purchased a OEM Stihl gaske/seal kit for a 066. Crankcase went together as its supposed to, but the inner diameter of the PTO side seal seems way to large for this crank. I mostly work on Husky saws, and I know some like the 372XP have a bushing between crank and the seal, but there was not one included with this saw and i don’t see one in the diagram. The crank OD is15mm, Was there two different crank sizes in these models? Anyone have any ideas?

 

[Bob Hedgecutter]

Yes there were two different cranks, two different case and 2 different oil seals.
Sounds like you have the crank that uses an 8mm nut to hold the flywheel in place and a 10mm nut crank seal.
Off the top of my head the crank tails were 12mm and 13mm for the 8mm nut and the 10mm nut respectively.
Then you get into the whole short case/long case- poly flywheel/alloy flywheel thing.

 

[uziduzit9mm]

Yes there were two different cranks, two different case and 2 different oil seals.
Sounds like you have the crank that uses an 8mm nut to hold the flywheel in place and a 10mm nut crank seal.
Off the top of my head the crank tails were 12mm and 13mm for the 8mm nut and the 10mm nut respectively.
Then you get into the whole short case/long case- poly flywheel/alloy flywheel thing.

Appreciate the info. thank you

 

[Bob Hedgecutter]

Okay 15mm then, not 13mm
15mm should be the late style 066/660 seal 15 x 22 x 4?
Will have to check service manuals for a part number.

 

[uziduzit9mm]

Okay 15mm then, not 13mm
15mm should be the late style 066/660 seal 15 x 22 x 4?
Will have to check service manuals for a part number.

I figured out my issue, I really appreciate the help, now i need to figure out the coil i need for a two key flywheel

 

[Bob Hedgecutter]

https://www.arboristsite.com/thread...ll-mattering-ignition-thread-volume-2.283569/

 

[uziduzit9mm]

https://www.arboristsite.com/thread...ll-mattering-ignition-thread-volume-2.283569/

wow that’s a pretty detailed write up thaqnks again

 

[Bob Hedgecutter]

wow that’s a pretty detailed write up thaqnks again

Very good resource and available free for view on here.

 

[Gord404]

ya I have a short block with a poly flywheel and a decomp- evedently these are factory just befor long block and original plastics with the decomp hole

 

[L34]

ya I have a short block with a poly flywheel and a decomp- evedently these are factory just befor long block and original plastics with the decomp hole

Yep we discussed this before Gord.
I have the sister saw.

 

[Vintage Engine Repairs]

Yep we discussed this before Gord.
I have the sister saw.

Yeah I think I have the same - short block, ally flywheel.

 

[Gord404]

Beauty- better pull mine out and do a little work on it- got it, fired it up and put it away till I have time to get at it and go over it.- soon

 

[L34]

Yeah I think I have the same - short block, ally flywheel.

View attachment 1134734

Hi Tom
should be short block poly wheel.

 

[Vintage Engine Repairs]

Ah Okk mines ally

Hi Tom
should be short block poly wheel.

 

[L34]

Yer all ally wheels are short tank.

 

[uziduzit9mm]

So I took a chance and picked up this seal on amazon https://www.amazon.com/dp/B09WNKFHRB?psc=1&ref=ppx_yo2ov_dt_b_product_details because my case is new style 22mm but crank at flywheel is the smaller old style 13.5 mm. I did a pressure check and it holds great. Ran the saw for about 20 min, no issues so far. for anyone looking to do same this may be a solution.

 

[red54]

my old 066 doesn't have the decomp , just the "soft start' handle, which ripped right off. I prime it for a 1 pull start...

 

[HansFranz]

my old 066 doesn't have the decomp , just the "soft start' handle, which ripped right off. I prime it for a 1 pull start...

I have a 660 with the decomp blocked off. I switched to the D-handle (from the 460 Rescue) and modified it to add a coil spring where the rope goes through (effectively converting it into a "soft start" D-handle), which saves my hand sometimes.