Stihl 051 rebuild questions

[Farmerboy]

Ok, so I’m rebuilding this soon to be 051 (from TS510 parts) with the idea to use as a dedicated chainsaw mill with auxiliary oiler. I have 2 questions:

1) I have a new aftermarket cylinder kit that has a squish of .050” with no base gasket. Is this acceptable for this saw?

2) on the pic below, that green rubber. Is that the crankcase seal? I’m assuming because I can’t see another one inside there. It seems to be be a different seal from the replacements I received.

 

[Ted Jenkins]

I looked through a couple manuals that I have and I think this correct. I do not have an 051 but believe they are the same or similar to what I have. The green thingy that you have pictured is the OEM type seal. On many models there is a spacer/bushing that goes around the crank shaft to take up the space near the seal to make a good seal. If you have the correct replacement seals one is for the magneto side and one is for the clutch side and yes they are often two very different sizes. If you can determine that they are working well and bearings are tight then leave them alone for a few years. Thanks

 

[ML12]

Post your question here: https://www.arboristsite.com/community/threads/050-051-075-076-info-thread.169996/

all I know about that series of saws is that there were a lot of changes made through the production run so you need to be careful when ordering spares.