Echo CS 355T chain saw crankshaft question (Plastic attachments??)

(Account Closed) · Dec 3, 2018

Working on a customers CS 355T chain saw that locked up.

Upon tear down, I found the crankshaft has TWO sets of plastic "parts" attached to the crankshaft. One set came off and locked up the engine. No other damage to the engine once the debris was removed.

The parts fisch, for a new crank does NOT show these plastic parts..

Masking tape is attached to remaining plastic part. The metal wire with loop ends hold the plastic parts to the crank..

I suspect I'll be removing the other and re-assembling (as a new crank doesn't have them).

I've never seen a two stroke with this part attached to the crank.

Any downsides removing them?

Anyone know what their for?

bertsmobile1 · Dec 3, 2018

SRTsFZ6 said:
Working on a customers CS 355T chain saw that locked up.

Upon tear down, I found the crankshaft has TWO sets of plastic "parts" attached to the crankshaft. One set came off and locked up the engine. No other damage to the engine once the debris was removed.

The parts fisch, for a new crank does NOT show these plastic parts..

Masking tape is attached to remaining plastic part. The metal wire with loop ends hold the plastic parts to the crank..

I suspect I'll be removing the other and re-assembling (as a new crank doesn't have them).

I've never seen a two stroke with this part attached to the crank.

Any downsides removing them?

Anyone know what their for?

They are packing pieces designed to reduce the total air volume inside the crankcase and thus increase the primary compression.
Without them the saw will have much smaller balls.

(Account Closed) · Dec 3, 2018

bertsmobile1 said:
They are packing pieces designed to reduce the total air volume inside the crankcase and thus increase the primary compression.
Without them the saw will have much smaller balls.

Ok, thanks...

BlazNT · Dec 6, 2018

Think that the crank would have been balanced with them so way more vibration if removed.

(Account Closed) · Dec 6, 2018

BlazNT said:
Think that the crank would have been balanced with them so way more vibration if removed.

The weight is negligible... The crank is balanced as one counter weight has a very smooth groove MACHINED (not from damage) in it..

As noted, it's apparently to reduce the volume of air in the lower end for increased power.

Every parts site I've gone to does not show the stuffers on the crank, just as pictured below.

I'm waiting on sealer for the cases and will be leaving the remaining the one on.
I'll know how well it runs as my customer has three, 355Ts, so I am familiar with their performance, should be assembled tomorrow (Friday)

Here is a picture from the Echo SHOP manual, (no stuffers):

Echo CS 355T chain saw crankshaft question (Plastic attachments??)

More options

(Account Closed)

Well-Known Member

bertsmobile1

Lawn Royalty

(Account Closed)

Well-Known Member

BlazNT

Lawn Pro

(Account Closed)

Well-Known Member

Footer Links 1

Footer Links 2