How hard is it to rebuild an earthquake carb?

[Softdraw]

My earthquake cs4518 quit midcut. I refilled the gas and restarted it with ease but it wouldnt run or even idle. My mechanic said the carb needed to be rebuilt but I declined--thats too expensive for a cheap saw. I found some info in the lengthy earthquake thread and I have watched a couple of carb rebuild videos, but, generally, is that something Joe homeowner can do with the right kit? Is it even worth it?

 

[s sidewall]

What's $10 for a kit and some cleaning, outweighs a new saw.

Steve Sidwell, Samsung On5 using Tapatalk

 

[Softdraw]

What's $10 for a kit and some cleaning, outweighs a new saw.

Steve Sidwell, Samsung On5 using Tapatalk

Is it something a guy with average mechanical skills can do? I don't tinker with my saws like the majority of posters here, but the process doesn't look too tough. Am I right on that?

 

[dswensen]

Not hard at all, assuming you have some mechanical skills. Even if you don't it's not that difficult. When taking the carb apart PAY ATTENTION to the order the old parts come out and the orientation of the parts in relation to the associated gaskets (as in which goes on first, gasket or part). When you get done, there should not be a lot of rebuilt kit parts left. HOWEVER, some kits come with gaskets for several different types of carbs, so extra gaskets are possible.

Your sudden "failure" after a refill sounds like a piece of gunk is clogging a passage, or more likely the screen after the metering needle in the carb. A saw that new probably doesn't need a carb re-build unless it's been neglected. Take it apart and clean it first. What do you have to lose, but some time?

Another tip - the gaskets are likely stuck the carb/body or covers. They can be carefully removed with a razor blade. CAREFULLY!

 

[blsnelling]

Died mid cut does not sound like a carb issue. I'd be checking the piston.

 

[dswensen]

Died mid cut does not sound like a carb issue. I'd be checking the piston.

I am assuming (perhaps incorrectly) that the OP's saw ran out of fuel mid-cut since he refilled it.

 

[Softdraw]

I did run out of fuel. However, the piston suggestion raises another question: is the saws failure to start after refueling an issue commonly associated with carb problems? I don't understand how the saw could run as smoothly as it was, start after refueling, and then just not run. The subsequent diagnosis was a carb problem--but does that make sense? How can a carb go from running well to not running at all (or starting and then dying). Does that make sense?

 

[Softdraw]

Not hard at all, assuming you have some mechanical skills. Even if you don't it's not that difficult. When taking the carb apart PAY ATTENTION to the order the old parts come out and the orientation of the parts in relation to the associated gaskets (as in which goes on first, gasket or part). When you get done, there should not be a lot of rebuilt kit parts left. HOWEVER, some kits come with gaskets for several different types of carbs, so extra gaskets are possible.

Your sudden "failure" after a refill sounds like a piece of gunk is clogging a passage, or more likely the screen after the metering needle in the carb. A saw that new probably doesn't need a carb re-build unless it's been neglected. Take it apart and clean it first. What do you have to lose, but some time?

Another tip - the gaskets are likely stuck the carb/body or covers. They can be carefully removed with a razor blade. CAREFULLY!

Thank you--one of the videos I watched showed the same thing--a clogged screen. However, a mechanic supposedly looked at it. If so, shouldn't he have caught that? I don't think he broke the saw down entirely but I know he checked the air filter.

 

[s sidewall]

Sounds like he looked at it, did he take the carb apart or just assumed it was the carb. Is there any water in the gas? Is the fuel filter clogged? I'd check the simple things first, got spark? Can you blow through the fuel filter? You see where I'm going.

Steve Sidwell, Samsung On5 using Tapatalk

 

[dswensen]

Thank you--one of the videos I watched showed the same thing--a clogged screen. However, a mechanic supposedly looked at it. If so, shouldn't he have caught that? I don't think he broke the saw down entirely but I know he checked the air filter.

Honestly? I doubt he looked (surely, I don't KNOW), but the price to rebuild a carb would have (should have?) covered just about anything you'd want to fix inside, so he likely did you a favor not tearing into it ($$) just to look. You have to remove the carb and disassemble it just to see the screen. By then, for a mechanic on the clock, it would have made more $ sense to install new re-build parts rather than the old ones.

Could it die that quickly? Sure, if like Brad was thinking, the piston roached, or if like I was thinking, there was a clog. Brad's diagnosis would have been a quick death after re-fueling; mine would have been a bit slower (as fuel had to move to create the plug). You say it restarted but not how long it "ran" after refueling.

 

[middleagemutant]

What about checking the vent

 

[Softdraw]

Honestly? I doubt he looked (surely, I don't KNOW), but the price to rebuild a carb would have (should have?) covered just about anything you'd want to fix inside, so he likely did you a favor not tearing into it ($$) just to look. You have to remove the carb and disassemble it just to see the screen. By then, for a mechanic on the clock, it would have made more $ sense to install new re-build parts rather than the old ones.

Could it die that quickly? Sure, if like Brad was thinking, the piston roached, or if like I was thinking, there was a clog. Brad's diagnosis would have been a quick death, or after re-fueling; mine would have been a bit slower (as fuel had to move to create the plug). You say it restarted but not how long it "ran" after refueling.

The more I read, the more I think something clogged the screen or carburetor itself. This mechanic has done good work in the past and I did tell him I didn't want to spend a fortune on a cheap saw, so it makes sense he didn't open the whole thing up. I didn't know how much you had to do to get inside. He probably didn't go past checking the air filter. The symptoms seem to show a fuel starvation problem, so I assume he checked the fuel lines--that isn't too hard, I don't think. If they checked out (and they should have, given my description of the problem), that leaves the carb. The saw ran well for a couple of hours before stalling. I can't believe the carb would suddenly quit, or the lines suddenly go bad, without showing problems before. Then, it would start easily after refueling and pumping the bulb but it wouldn't run or even idle. That tells me the fuel in the cylinder burns but something is choking the fuel from the tank to the cylinder. I am not sure what a bad cylinder would do but the saw starts and runs as well as ever for the few seconds it burns the fuel directly from the bulb before it bogs and dies. Again, not knowing what a bad cylinder would cause but the machine seems to run well when there is fuel in the cylinder.

Thank you for your help.

 

[klaus von herten]

Another vote for rebuilding the carb. I am a newbie and I just rebuilt one.

Sent from my SM-G935V using Tapatalk

 

[dswensen]

One more thought - check to make sure the fuel line in the tank still has the fuel filter attached to the end. They can come off the end of the line and, since they are weighted, if they are not there, the end of the fuel line can end up in weird places inside the tank.