Help on indentifying 066 cylinder

[Sauen]

Hi all,
I am in the process of rebuilding several 066s and 064, so always keen on buying cylinders for them. I ran across this one and would like to hear thoughts on whether it’s worth it to keep or just pass on.
It’s a decomp KS one with a thick base, 54mm. Upon purchasing I was a little skeptical of it really being a 54mm and not a 52mm ms650 jug. These are more often KS cylinders I believe, where the later 066s are Mahle or just Stihl branded? The red light cylinders are KS but have thin bases right?
Turns out the seller was correct on it being a 066 one. Now I had never seen this version of 066 cylinder, does anyone know which years these were made and how they run?
I have not timed it yet, will do it when I get back home.

Olivier

 

[Hinerman]

@jacob j.

 

[jacob j.]

You being in Europe makes sense, they used the Kolbenschmidt cylinders for a much longer duration on the Euro and Asian saws.

That's likely a mid-90's flat top, poly flywheel saw cylinder from just before the conversion to the bubble-top saws.

 

[BonScott46]

Hi all,
I am in the process of rebuilding several 066s and 064, so always keen on buying cylinders for them. I ran across this one and would like to hear thoughts on whether it’s worth it to keep or just pass on.
It’s a decomp KS one with a thick base, 54mm. Upon purchasing I was a little skeptical of it really being a 54mm and not a 52mm ms650 jug. These are more often KS cylinders I believe, where the later 066s are Mahle or just Stihl branded? The red light cylinders are KS but have thin bases right?
Turns out the seller was correct on it being a 066 one. Now I had never seen this version of 066 cylinder, does anyone know which years these were made and how they run?
I have not timed it yet, will do it when I get back home.

OlivierView attachment 359301View attachment 359302

Very nice.

 

[Sauen]

You being in Europe makes sense. they used the Kolbenschmidt cylinders for a much longer duration on the Euro and Asian saws.

That's likely a mid-90's flat top, poly flywheel saw cylinder from just before the conversion to the bubble-top saws.

Thank you Jacob! Exactly the information I was looking for!
Should go nicely on my poly flat top then.

 

[Sauen]

Port numbers look to be 96/118.5/78.5 with the squish at 0.5mm/20 thou, which is not the low exhaust I was hoping for. Transfers and intake do allow for a little lowering of the cylinder to make up for that?
I'm planning to cut about 1mm/ 40 thou out of the squish band, which should make it end up at about 99/122.5/81.5.
Next will be to leave the exhaust and lowers untouched and set the transfers at 120 with the exhaust side opening a little earlier. Then set the intake back to ~78 with some epoxy and widen it some.

What are your thoughts on this approach? Saw porting and modifications on saws in general is uncommon here in the Netherlands, so I'm glad to be able to learn from you guys on this forum. Thanks

 

[srcarr52]

Port numbers look to be 96/118.5/78.5 with the squish at 0.5mm/20 thou, which is not the low exhaust I was hoping for. Transfers and intake do allow for a little lowering of the cylinder to make up for that?
I'm planning to cut about 1mm/ 40 thou out of the squish band, which should make it end up at about 99/122.5/81.5.
Next will be to leave the exhaust and lowers untouched and set the transfers at 120 with the exhaust side opening a little earlier. Then set the intake back to ~78 with some epoxy and widen it some.

What are your thoughts on this approach? Saw porting and modifications on saws in general is uncommon here in the Netherlands, so I'm glad to be able to learn from you guys on this forum. Thanks

You can leave the intake around 81 and it will be fine. 98.5 on the exhaust is a good goal too.

I think I’m usually around 22-23 blowdown on these and I work over the lowers a fair amount.

 

[huskihl]

You can leave the intake around 81 and it will be fine. 98.5 on the exhaust is a good goal too.

I think I’m usually around 22-23 blowdown on these and I work over the lowers a fair amount.

I’d be happy to land there. Widen the exhaust and lowers a little and it’ll run well