Echo cs260-shindaiwa 269t problem

[chrissalas1]

Hello

I have on my bench one cs260 and one 269t that came about the same day and i cannot make them run good.It is actually the same saw with different color,stickers.....etc
The people came in to my shop with the same problem.The saws were bogging when accelerating.The first thing did was pressure and vac tested and found air leak at the same point at the two saws.They were leaking from the bottom engine cover sealant.So took them apart and cleaned piston,cylinder,installed new seals,bearings,piston rings and new sealant.The Piston and cylinder on both are in very good shape without scratches.Fired up and still they not running good.I adjusted the carbs L about 3 turns out which is the point when they accelerate the best but still have intermittent starvation when i instanly open the throttle wide open.The only way to to make them running about 11000 rpm is to turn the H needle ALL the way in.Echo says that max rpm for these models are 12.500.I have pressure vac tested again with good results.Pressure tested fuel lines,installed new fuel filter,new carbs with no difference.Yesterday I tested the compression and on one is 110psi and on the order 100psi.Whats you opinion?
Maybe the pistons are a little oval and thats why i have little compression?

 

[beaglebriar]

Hello

I have on my bench one cs260 and one 269t that came about the same day and i cannot make them run good.It is actually the same saw with different color,stickers.....etc
The people came in to my shop with the same problem.The saws were bogging when accelerating.The first thing did was pressure and vac tested and found air leak at the same point at the two saws.They were leaking from the bottom engine cover sealant.So took them apart and cleaned piston,cylinder,installed new seals,bearings,piston rings and new sealant.The Piston and cylinder on both are in very good shape without scratches.Fired up and still they not running good.I adjusted the carbs L about 3 turns out which is the point when they accelerate the best but still have intermittent starvation when i instanly open the throttle wide open.The only way to to make them running about 11000 rpm is to turn the H needle ALL the way in.Echo says that max rpm for these models are 12.500.I have pressure vac tested again with good results.Pressure tested fuel lines,installed new fuel filter,new carbs with no difference.Yesterday I tested the compression and on one is 110psi and on the order 100psi.Whats you opinion?
Maybe the pistons are a little oval and thats why i have little compression?

If it's a 10mm sparkplug they always read low with a compression test. You have to use an adapter and the Schrader valve is no longer at the end of the hose, gives you a low reading.

Did you replace the fuel lines? If they are soft from ethanol fuel the vacuum can close them off under throttle.

 

[chrissalas1]

If it's a 10mm sparkplug they always read low with a compression test. You have to use an adapter and the Schrader valve is no longer at the end of the hose, gives you a low reading.

Did you replace the fuel lines? If they are soft from ethanol fuel the vacuum can close them off under throttle.

They are 14mm spark plug.Mine compression tester is specific for small engines-so it has the valve at the end and it has small hose.I did not replaced the fuel lines because they passed the pressure test.

 

[Mutley]

G'day chrissalas, did you happen to resolve this issue by any chance?

I'm having exactly the same thing happen on an old 350TES that I have.

 

[Nutball]

Are the spark screens clean? My 271t has been slowly getting worse over time about getting lean when accelerating. Every few months I make the low speed a tad richer, and hold partial choke while running full throttle until it transitions better and builds gas tank pressure. Chainsaws do use tank pressure right? I've always assumed so. And if that's the case, maybe over time the cap seal or tank vent lets pressure out faster than usual.

 

[Dub11]

Hello

I have on my bench one cs260 and one 269t that came about the same day and i cannot make them run good.It is actually the same saw with different color,stickers.....etc
The people came in to my shop with the same problem.The saws were bogging when accelerating.The first thing did was pressure and vac tested and found air leak at the same point at the two saws.They were leaking from the bottom engine cover sealant.So took them apart and cleaned piston,cylinder,installed new seals,bearings,piston rings and new sealant.The Piston and cylinder on both are in very good shape without scratches.Fired up and still they not running good.I adjusted the carbs L about 3 turns out which is the point when they accelerate the best but still have intermittent starvation when i instanly open the throttle wide open.The only way to to make them running about 11000 rpm is to turn the H needle ALL the way in.Echo says that max rpm for these models are 12.500.I have pressure vac tested again with good results.Pressure tested fuel lines,installed new fuel filter,new carbs with no difference.Yesterday I tested the compression and on one is 110psi and on the order 100psi.Whats you opinion?
Maybe the pistons are a little oval and thats why i have little compression?

Have you thought about rebuilding the carb?

 

[Mutley]

Have you thought about rebuilding the carb?

That is my initial thought too, but the saw has way too many hard hours on it to spend any $$$ repairing it.

 

[Mutley]

Are the spark screens clean? My 271t has been slowly getting worse over time about getting lean when accelerating. Every few months I make the low speed a tad richer, and hold partial choke while running full throttle until it transitions better and builds gas tank pressure. Chainsaws do use tank pressure right? I've always assumed so. And if that's the case, maybe over time the cap seal or tank vent lets pressure out faster than usual.

Mine's muffler modded, the muffler is wide open & there is no spark arrester in place. Been that way for years.

It's bogging on spooling up. It runs perfectly if I can get past the L screw bog though. Does it after about the 3rd cut when I re-tune the L screw, then every cut afterwards.

 

[Dub11]

That is my initial thought too, but the saw has way too many hard hours on it to spend any $$$ repairing it.

Rebuilding the carb is way easier than what you've already done.

 

[Mutley]

Rebuilding the carb is way easier than what you've already done.

Opening up the muffler didn't cost me anything. A carb kit would cost. If the saw had a lot less hours on it, I'd do it, but it's a work saw & it's old.

 

[Nutball]

Not too big of a muffler mod? That can lean out the low end. I found a MM 290 at work, it always idled a bit lean. I thought I fixed it by tuning the low end richer, and it ran and idled well, but the next day it would always fast idle and spin the chain. Haven't had a chance to retune it yet.

 

[Mutley]

That's a good thought, but it was running like a champ with the modded muffler for about 1,000 - 1,500 hours before it started playing up (it's my go to work saw)

I have a donor saw in my parts box & played a game of mix & match today. Let's see what tomorrow brings lol!

 

[chrissalas1]

Guys sorry for the late response.I installed new carb but was working the same.Changed fuel lines and......voila!!!Had the same problem with an 351wes last week and was also the fuel lines.But what i don't understand is that original echo fuel lines are very soft brand new.