Echo chainsaw

[Charles in Aus.]

I bought my first chainsaw in the March of 1982 . A Kioritz Echo CS315 fitted with a Walbro WA33 carburettor.
I used it a lot for domestic work up until '92 when I bought my farm and a Sthil Farm Boss to tend to it . It was a favourite of mine and I would like to use it again on occasion .
It suffered from bogging down on acceleration when I retired it , recently I have tried to revive it with no luck .
Spark is fine , fuel lines and filter new , CJ8 plug good , air filter clean , carburettor diaphragms not replaced but intact and supple , carburettor cleaned in an ultrasonic bath , exhaust clear .
The problem persists , starts well enough , idles smoothly , accelerates to mid rpm , then stalls if pushed further , recovers if you back off .
Any suggestions on causes ?
I have a carb kit on order ,though I suspect that won't solve the problem .

 

[DaveBN]

Maybe do a compression check but it sounds like a bad coil to me. They will test good and work at low RPM but fail at higher RPM's.
Dave

 

[Duner Wi]

I assume adjusting the carburetor does nothing. How about partial choke? Not saying it isn't the coil.

 

[Gary Reif]

Does it have a spark arrester on the muffler? If so I would check it for carbon buildup. That's what happened to my sthil string trimmer. After removing it it's been running great for years.

 

[Wdj]

My older Echos have a flexible tube connecting the carburetor to the cylinder. Over time it deteriorates and developes vacuum leaks. The symptoms are not quite what you describe but it is a common problem on those saws.

 

[Fawteen]

Does it have a spark arrester on the muffler? If so I would check it for carbon buildup. That's what happened to my sthil string trimmer. After removing it it's been running great for years.

Showing classic symptoms of this ^^^

 

[Charles in Aus.]

First things I did were to ensure the exhaust was clear and fuel supply was good , then tried a spark indicator .
It does spark but not really brightly , I put this down to the small size , perhaps the coil is breaking down . I coukd try using the indicator while it's running , that might show a breakdown under load .
Its a shame really , such a well built and balanced saw .
I've not ever tried to check compression on such a small engine, I must see if the adapters on my gauge will fit .

 

[Charles in Aus.]

My older Echos have a flexible tube connecting the carburetor to the cylinder. Over time it deteriorates and developes vacuum leaks. The symptoms are not quite what you describe but it is a common problem on those saws.

Something I will look into , I noticed the tube on mine . It looked fine but I didn't really examine it too closely . Thanks.

 

[Charles in Aus.]

Maybe do a compression check but it sounds like a bad coil to me. They will test good and work at low RPM but fail at higher RPM's.
Dave

Thanks Dave , another lead to follow up . Unfortunately new coils are no longer available. That may be a death sentence for it .

 

[560Dennis]

Are the diaphragm flexible ? Change them out.

 

[Charles in Aus.]

Are the diaphragm flexible ? Change them out.

Surprisingly almost like new !
I've not seen ones as good in machines only a few years old .
Its probably an indication of the original quality of the machine .

 

[Mike(NEOhio)]

I have that same model I bought for my dad back around that time. A small one. It never ran consistently and on hot days, trying to refill the gas it would boil up as it was poured in. Had to add an ounce or two at a time.

 

[DanielW]

It does indeed sound like either a plugged spark arreator or being set too rich. Have you adjusted the carb? I think a carb kit and tuning is in order. What does it have for a tank vent? Some of those Echos had smaller, check-valve type tank vents that commonly got stuck and caused grief when the tank couldn't vent at the required rate for higher rpm. Try running it for a bit with the cap loose so it can vent freely.

My guess is a carb kit and tuning will get her going again. Those are pretty common symptoms in any old saw. Between the two farms and bushes, and my six old sawmills, we have a lot of use for chainsaws. Must have about two dozen. Mostly Stihl, but some Echo and Husky. And the symptoms you describe are quite common, and usually pretty easily fixed.

 

[DanielW]

I have an ECHO I bought for my dad back around that time. A small one. It never ran consistently and on hot days, trying to refill the gas it would boil up as it was poured in. Had to add an ounce or two at a time.

Plugged tank vent - I'd bet dollars to buttons. Not uncommon symptoms in old saws - especially Echo's that had the check valve style of tank vent. If the tank vent looks like this, it should be checked cleaned/replaced:

 

[Duner Wi]

ECHO coil investigation disection.

Ignition coils again. - Chainsaw Collectors.se

 

[Charles in Aus.]

ECHO coil investigation disection.

Ignition coils again. - Chainsaw Collectors.se

This saw still uses points Dunner , i have checked abd adjusted them but havent really thought of condenser failure before , thanks .

 

[Jack345]

Its about time for those crank seals to leak, not a hard job but takes time & shops charge $, Seals less than $5.00 each.Those are good saws & worth a repair job.