Question about Rotary Chainsaws eg KMS-4

[Matthew Donoghue]

Hi Guys,

This is my first post here.

I am interested in small engines and in particular Rotary Chainsaws like Sachs Dolmar KMS-4. I am hoping a knowledgeable person here can help me with a technical question...

How does the internal parts of a Rotary Chainsaw get lubricated? Such as the crankshaft bearings, the eccentric bearing and the gear teeth on the inside of the rotor?

Thanks,
Matt.

 

[RedneckChainsawRepair]

Know several that own and collect those and the other ones with Wankel.

I have a bunch saved on those and maybe the service manual and IPL is all here too. Have fun researching. http://chainsawrepair.createaforum.com/dolmar/sachs-dolmar-kms-4/

 

[Bill G]

Here is a KMS-4 that I have had for years

 

[heimannm]

The KMS4 uses mixed fuel just like any other 2 stroke engine so the internals are lubricated by the oil in the mix.



Mark

 

[RedneckChainsawRepair]

Here is their ad back then from thread I linked.

Pushing 50:1 because of less smoke and fumes.

 

[Matthew Donoghue]

Thanks for the replies, that is really interesting... I know a normal 2 Stroke the oil/gas mix goes past the rod and bearings before going into the engine. However with a 2 Stroke the pressure of the piston coming down helps push the oil/gas mix into the engine.

I guess with a rotary the rotor creates a slight vacuum which pulls the oil/gas mix into the engine.

I am just a beginner with chainsaws and small engines so I appreciate the answer and the photos. Great stuff guys.

Cheers,
Matt.