Echo timberwolf cs-590 fuel leaks out of compression switch

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it's not a 'compression switch', it's a compression release valve and additionally, there may very well be a particle of carbon or some debris blocking the seat which will allow a compression leak. remove it and inspect it with a magnifying glass, especially the seat and make sure it's clean and reinstall t. they really don't wear out but they can get fouled and leak. Just a starting aid and with mine I don't use it anyway. I'll roll the saw (cold) to where the piston is close to TDC and attempt to start it and if it don't fire (which is pretty well the norm on the first pull cold). I repeat the process until it fires and then advance the choke lever from full choke to partial choke and start it.

With a 50cc engine, the compression release is really not necessary unless you are a gal or a woose.

The rollover to TDC works for me quite well.
 
One thing about the stock carb on a Timber Wolf is, it's really not big enough (venturi wise) take full advantage of the power capability the motor can make, IOW, it's being throttled ( choked back). I suggest at some point replacing it with a carb from the next model up in size, but don't buy a cheapo Amazon Chinese carb, stick with a Walbro and open up the muffler as well. I completely removed the inner baffle between the can and the muffler director but I left the spark screen intact. You can also remove the muffler guts but it's an involved job that takes time and patience and a Dremel and some carbide burrs. I also removed the limiter caps, Echo tends to tune the saws on the rich side stock so leaning it out a bit will help the power output but make sure your fuel-oil mix is correct (I use canned fuel at the 40-1 ratio) for the first couple tanks to insure everything is bedded in correctly before going to 50-1 canned fuel. The carb along with the muffler mod will let the motor develop more grunt without modding the port timing at all.

Finally, if you keep the stock air filter (I didn't, I went to an oiled foam Nick Stokel air cleaner), find a suitable sized 'O' ring at your local hardware store and fit it into molded in boss on the backside of the air cleaner element. The molded in hole in the element is way too large and allows fines to enter the carb and intake stub but it's an easy and cheap fix.

Presently, mine will pull a 24" bar with full chipper 325 chain and lowered depth gages, no issue and no 4 stroking either. I also opened up the bar oiler metering screw on the bottom of the saw a bit as well. Echo's are all adjustable while other saws (I won't mention any names) aren't easily adjustable and bar oil is pretty cheap even today while bars aren't and neither are chain loops. In my opinion, the Timber Bear is a damn good saw for a damn good price. with some simple and not overly expensive modifications other than a Walbro Carb with a larger throat.

I have no desire to port it or fiddle with it internally.
 
Metering lever looks good. Check the fuel pump and metering diaphragms, if they feel stiff your gonna need a rebuild kit. If they’re still nice and flexible reassemble the carb. Make sure you got fresh fuel in the tank. Also, pull the muffler and inspect the piston.
 
Sidecarflip said:
it's not a 'compression switch', it's a compression release valve and additionally, there may very well be a particle of carbon or some debris blocking the seat which will allow a compression leak. remove it and inspect it with a magnifying glass, especially the seat and make sure it's clean and reinstall t. they really don't wear out but they can get fouled and leak. Just a starting aid and with mine I don't use it anyway. I'll roll the saw (cold) to where the piston is close to TDC and attempt to start it and if it don't fire (which is pretty well the norm on the first pull cold). I repeat the process until it fires and then advance the choke lever from full choke to partial choke and start it.

With a 50cc engine, the compression release is really not necessary unless you are a gal or a woose.

The rollover to TDC works for me quite well.
Click to expand...
"Gal or woose" lol
 
Sidecarflip said:
One thing about the stock carb on a Timber Wolf is, it's really not big enough (venturi wise) take full advantage of the power capability the motor can make, IOW, it's being throttled ( choked back). I suggest at some point replacing it with a carb from the next model up in size, but don't buy a cheapo Amazon Chinese carb, stick with a Walbro and open up the muffler as well. I completely removed the inner baffle between the can and the muffler director but I left the spark screen intact. You can also remove the muffler guts but it's an involved job that takes time and patience and a Dremel and some carbide burrs. I also removed the limiter caps, Echo tends to tune the saws on the rich side stock so leaning it out a bit will help the power output but make sure your fuel-oil mix is correct (I use canned fuel at the 40-1 ratio) for the first couple tanks to insure everything is bedded in correctly before going to 50-1 canned fuel. The carb along with the muffler mod will let the motor develop more grunt without modding the port timing at all.

Finally, if you keep the stock air filter (I didn't, I went to an oiled foam Nick Stokel air cleaner), find a suitable sized 'O' ring at your local hardware store and fit it into molded in boss on the backside of the air cleaner element. The molded in hole in the element is way too large and allows fines to enter the carb and intake stub but it's an easy and cheap fix.

Presently, mine will pull a 24" bar with full chipper 325 chain and lowered depth gages, no issue and no 4 stroking either. I also opened up the bar oiler metering screw on the bottom of the saw a bit as well. Echo's are all adjustable while other saws (I won't mention any names) aren't easily adjustable and bar oil is pretty cheap even today while bars aren't and neither are chain loops. In my opinion, the Timber Bear is a damn good saw for a damn good price. with some simple and not overly expensive modifications other than a Walbro Carb with a larger throat.

I have no desire to port it or fiddle with it internally.
Click to expand...
That all sounds really great and cool, love to do that sometime, but I'm just trying to get it to start at the moment
 
Sidecarflip said:
it's not a 'compression switch', it's a compression release valve and additionally, there may very well be a particle of carbon or some debris blocking the seat which will allow a compression leak. remove it and inspect it with a magnifying glass, especially the seat and make sure it's clean and reinstall t. they really don't wear out but they can get fouled and leak. Just a starting aid and with mine I don't use it anyway. I'll roll the saw (cold) to where the piston is close to TDC and attempt to start it and if it don't fire (which is pretty well the norm on the first pull cold). I repeat the process until it fires and then advance the choke lever from full choke to partial choke and start it.

With a 50cc engine, the compression release is really not necessary unless you are a gal or a woose.

The rollover to TDC works for me quite well.
Click to expand...
TDC?
 
Gord404 said:
The stock fab on a 590 timberwolf has a small hole in the top of the main jet which kicks in to prevent over reving,
Click to expand...
Highly unlikely! Unburned hydrocarbons are a strict no-no to the clean air authorities i.e. EPA in the U.S. This type of rev limiter disappeared about 2-3 decades ago.
 
cycloptico said:
Just wanted to thank all of yall again, props to who's running the joint, and props to everyone in it
Click to expand...
So what do you think the difference was?

Asking as someone who inherited a CS-590 brand new, ran it twice in the last two months, and now has a chainsaw that won’t start. I’ve pulled the spark plug to clear a flood, bought a new spark plug, bought high end premix gas, … and no crank.
 
pjl123 said:
So what do you think the difference was?

Asking as someone who inherited a CS-590 brand new, ran it twice in the last two months, and now has a chainsaw that won’t start. I’ve pulled the spark plug to clear a flood, bought a new spark plug, bought high end premix gas, … and no crank.
Click to expand...
It is either #1 still flooded or #2 burned up.

To verify or eliminate #2 remove the muffler and post photos of the piston and ring(s) as seen through the exhaust port.

BTW, if this is a new saw why isn't this a warranty issue?
 

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