I picked up Wanderweg’s Echo CS-370 that he was offering here on FHC. If you recall, it had a broken handle. I was able to get a nice used handle/fuel tank assembly and rebuilt the saw. It was running quite well immediately after the repair. Throttle was responsive and everything seemed fine. The next morning it fired right up, ran for about 30 seconds and died. Now I can’t get it to even run for a brief second with starter fluid, not even a sputter. It’s getting a spark with the original plug and a spare. I’m at a loss. Any suggestions would be greatly appreciated.
Fuel filter came off, fuel line vacuumed the trash in the tank, carb screen is packed with debris. That’s my spit ball.
If you remove the fuel cap and reinstall it, then it runs but dies again, I’d suspect a tank venting issue.
If everything is as you say and you can’t get it to sputter with starting fluid, I’d say you either don’t have compression or you’re getting spark at the wrong time. Suck, squeeze, bang, blow. And all of that has to happen at the right time. I’ll be interested to hear what you find.
One other thought, I’m guessing you’re checking for spark with the plug removed. Your spark may be weak enough that it’s not firing under compression but you can see it with the plug removed. It needs a lot more energy to jump that gap under compression.
I planned on spending time on it today but decided I’d rather split wood. It was much needed therapy.
Sure did. Removed it and verified the spark was at the beginning of my troubleshooting list. I can run it up the street tomorrow and get a compression test and maybe pick up a pointer suggestion from the service tech as well.
Finally got a chance to get the 370 to my buddies for a compression test, came in at 180/182, so no issues there. Asked me to leave it with him(thank God) and he’d call me when it’s running. Feels it’s something simple.
Looks like it’s time to take the 370 behind the barn and shoot it. My buddy called today and broke the news. It was giving high numbers on a compression test because the cylinder was flooded with fuel. Once he got everything cleared out, the compression was very weak. I guess I’ll bring it home and try to recoup some of the money I have in it by parting it out on eBay. Still can’t figure out why it ran good the first time I fired it up after replacing the handle/fuel tank assembly.
Remove the muffler and have a look at the piston through the exhaust port. If you don't see scoring, I'd think it's not time to part it.
Worst case it needs a piston and rings. Most likely it has some transfer, which is pretty easily cleaned.
I’m sure I’ll end up replacing the piston and rings but for the time being this saw is going on the back burner.
