TheRockyMountainKing
I could break an anvil with a feather duster!
I got a blown up 066 from my uncle, threw a new piston, rings, and jug in it. Just rebuilt the carb, all fuel lines, and an impulse line. It will pop but wont start. Help?
066 wont start
- Thread starter TheRockyMountainKing
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Adjust the carb,Turn high and low screws out one turn from stop.
Start there
Start there
TheRockyMountainKing
I could break an anvil with a feather duster!
Did that. Still not happy. Dont matter where i put them.
TheRockyMountainKing
I could break an anvil with a feather duster!
Nope, checked that 5 minutes before i started the thread. Its fine.
Check the switch, wires, in the different positions.
Will it continually pop and not fire or do you need to clean the plug every now and again? Every time I've had a saw pop and not fire after carb work it's because I forgot to slide the tit on the diaphragm into the notch on the metering lever, so it floods itself out.
Bearings and seals OK? Did you pressure and vacuum test? Is the fuel fresh?
Will it run a bit with some mix put in the carb?
TheRockyMountainKing
I could break an anvil with a feather duster!
Bearings all tight. Crank seals are old. It failed a leakdown test before i put a top end in it. Fuel is fresh.
TheRockyMountainKing
I could break an anvil with a feather duster!
Not really.
Meaning you fixed the leak first right ?
Did you use China crap parts or OEM?
TheRockyMountainKing
I could break an anvil with a feather duster!
It failed it because piston rings jug were worn out. I put in hyway brand stuff.
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Can you show us a photo of the worn out rings that failed?
Worn ring usually just = new rings and good to go- you replaced the entire top end, which in turn leads to thinking the top end was roached from an air leak (failed leak down test, seals are old).
Recent carb rebuild- download an 066 IPL and check the carb is assembled correctly.
If it is starved for fuel and not flooding- for some reason the fuel is not reaching the combustion chamber- could be the impulse line is incorrectly or loose fitting and not pulsing the pump diaphragm, was it an OEM replacement line- or fleabay cheapie? Impulse could be blocked. Or the carb assembled incorrectly.
Either way, if it pops, it should run if fuel was dribbled into the carb throat with the choke off, choke moved to "on" and the rope pulled.
Worn rings won't effect a pres/vac test.
OP, do a compression test on the saw and post the numbers.
Rings have not a thing to do with a failed vac pressure test, did you test after the new top end rebuild!
Unless it has an awful leak, like impulse not connected , or hole in manifold it should still run as far as air leak is concerned, even if not very well.
You have something else going on. Check compression and squish.
Remember, there are only three things. Compression ,fuel ,and fire at the right time.
You have something else going on. Check compression and squish.
Remember, there are only three things. Compression ,fuel ,and fire at the right time.
Binthewoods
ArboristSite Operative
Is fuel coming out the muffler? They’re easy to flood. Try a band around the throttle to hold it open and keep pulling, if flooded it’ll gradually pop and sputter better and better until it runs.
A tree removal company just dropped off an 066 to my shop today. Foreman said it would run a few minutes and die. I first removed the bar and chain and then checked the compression using the pull cord (hold and let go). It fell all by itself. Not good, I removed the muffler and checked the rings on the exhaust side. No rings remained in sight, so I removed the cylinder and piston. Top of piston was scorched.
Exhaust side of piston:
Intake side:
Even the rings on the intake side are almost frozen, what's left of them. Cylinder was worn really badly up near the top. Likely this engine ran hot and wasn't getting a good fuel mix, perhaps even burning straight gas. It only takes one tank to do it. I have no idea how it would even start and run for a short while. Regardless of cause, this engine needs a whole new top end. Not sure what else could have caused this destruction. Comments and suggestions welcome.
Exhaust side of piston:
Intake side:Even the rings on the intake side are almost frozen, what's left of them. Cylinder was worn really badly up near the top. Likely this engine ran hot and wasn't getting a good fuel mix, perhaps even burning straight gas. It only takes one tank to do it. I have no idea how it would even start and run for a short while. Regardless of cause, this engine needs a whole new top end. Not sure what else could have caused this destruction. Comments and suggestions welcome.
