Chainsaw Symptoms

[dboyd351]

Do not use compressed air on the carb again
Ultrasonic cleaner or carb cleaner

 

[singinwoodwackr]

I acquired a saw a while back that had been sitting a while... flushed tank, replaced lines & filter, cleaned & kitted carb. Ran fine for half a tank then started acting up, some investigation led to me finding the filter was blocked. Wrote of filter as a dud & fitted another new one, ran saw & same thing again. Replacing the filter for the third time I found a ball of goo floating around in the fuel tank. Don't know exactly what it was but I'm guessing it was stuck inside the tank & didn't dislodge when I flushed it

The black goo is what’s left of an old fuel line dissolved by ethanol gas.

 

[dboyd351]

First thing to do when you acquire older saws is flush and clean old tank and replace old fuel lines and filters. Then clean the carb in an ultrasonic cleaner and install a carb kit.
Often just doing those things will get them running.

If at all possible never use gas with ethanol in it.
If you do use gas with ethanol, dump out the tank, start the saw and run it until it dies to get the erhanol out.

Leaving ethanol laced fuel in any machine that sits for long periods of time without being used is asking for problems.

 

[MacAttack]

Yeah ethanol is the worst thing in something like a chainsaw.

 

[J D]

The black goo is what’s left of an old fuel line dissolved by ethanol gas.

The goo was more of an amber colour. Still could have been a fuel line, but none of the lines were missing... & around here it's unlikely there was any ethanol in the fuel.
At the time I suspected it was a lump of tree sap. The filter still looked like it was new too

 

[MacAttack]

Just for the sake of discussion, I've used more than a few AM Chinese made fuel lines and filters and never had one turn to goo or fall apart. I have had the cheap lines cut / tear more easily though.

 

[mattcasdorph]

Here is a video I made earlier today.

 

[singinwoodwackr]

The goo was more of an amber colour. Still could have been a fuel line, but none of the lines were missing... & around here it's unlikely there was any ethanol in the fuel.
At the time I suspected it was a lump of tree sap. The filter still looked like it was new too

Ah, amber is probably very old fuel that has turned to shellac. I got an 041 that had a crankcase full of it, many years ago. Guy said he hadn’t touched it in over 5 yrs

 

[MacAttack]

Sorry if this was already covered but did you flush the gas tank out good at some point?
It seems like your fuel system is getting plugged up with junk, even with a new filter you'll have problems if there's junk in the gas tank. I've had some gas tanks in saws that took some work to clean out all the crud from stale gas.

 

[mattcasdorph]

Sorry if this was already covered but did you flush the gas tank out good at some point?
It seems like your fuel system is getting plugged up with junk, even with a new filter you'll have problems if there's junk in the gas tank. I've had some gas tanks in saws that took some work to clean out all the crud from stale gas.

Yeah, it looks clean in the tank and I rinsed it a few times

 

[singinwoodwackr]

Here is a video I made earlier today.

Looks like your primer bulb is bad. I’ve had one that sucked air like that…replaced it, solved.
The return line just needs to barely be inside the tank, not down in the gas.
Wow, that’s a lot of crud getting through the fuel system.
Replace the filter and re-flush the lines.

Finished your vid. Links like you everything right

 

[mattcasdorph]

Looks like your primer bulb is bad. I’ve had one that sucked air like that…replaced it, solved.
The return line just needs to barely be inside the tank, not down in the gas.

The primer worked fine when I bypassed the carb. Also worked fine at the end when I purged it after cleaning the carb. And yeah, the return isn't long at all in the tank. Shouldn't be submerged. It ran at the end. I'm going to try finishing cutting a log in my yard. There was supposed to be thunderstorms earlier this evening so I didn't get to try it under load. I believe it will run like it was a few days ago when it ran good before it started bogging. Has more power than my old saw and did good. Im trying to clear some trees to do some grading and these two saw problems slowed me down. This saw here was getting me caught back up some with the work until it started the bogging crap. But it should be running ok again. I'll know tomorrow