Any Chinese chainsaw and chinese parts discussion

[Czed]

How did that chain file after you hit the nail?

I sharpened the chain after hitting dirt caked to the ash.
it doesn't appear soft it cut much better after sharpened most chain does after a couple passes with a file.

 

[p61 western]

I sharpened the chain after hitting dirt caked to the ash.
it doesn't appear soft it cut much better after sharpened most chain does after a couple passes with a file.

It's nice that it holds a edge. I have a China chain that I got with a bar that don't hold a edge for crap

 

[Czed]

It's nice that it holds a edge. I have a China chain that I got with a bar that don't hold a edge for crap

It's all I've been using on the first 372 the upstart I've only now sharpened it.
But i could have got a good batch for the price i like it especially cutting around fencelines my other chains are pricey lol

 

[p61 western]

It's all I've been using on the first 372 the upstart I've only now sharpened it.
But i could have got a good batch for the price i like it especially cutting around fencelines my other chains are pricey lol

It would be cool to see how it does with a square file or square grind. After I recover from buying the 281, I'm going to buy some of that chain.

 

[Mattyo]

Ok, my china saw runs like crap. It just doesn't have much power or compression. I changed carbs, not much help.

I went back to my build video...which is being saved now and will be uploaded asap... and saw that I widened the intake too much ... so I have a "side" free port out the intake. Would this wreck compression...and cause it to run poorly? compression is 125 psi at best. 036 squish.

 

[Terry Syd]

Blowing back out the intake during crankcase compression could definitely cause it to run poorly. I would expect that it would be most noticeable at idle. I'd just patch it with some GB Weld.

The low compression is a mystery. The intake port issue wouldn't affect the compression testing as the gauge is measuring the trapped air above the closing of the exhaust port. I'd try putting a bit of motor oil in the spark plug hole to see if there is a ring sealing problem.

 

[Mattyo]

The porting vid is uploading now....so you'll be able to see the side free port and tell me how big of a deal it is. Maybe I'll take off the carb and look at the ring ends.

It literally is half the speed of a stock 372...very little power.

On both the carbs...am and hd12 ....have to crank the idle screw all the way in.

 

[Czed]

I just matched the intake to the boot and slightly widened the port and widened the exhaust port didn't change timing all four run good do you have any pics of how much you widened the intake.

 

[Mattyo]

after looking at it again, its probably not the issue ... around the 43 min mark. and there are photos at the end of the vid:

 

[Czed]

after looking at it again, its probably not the issue ... around the 43 min mark. and there are photos at the end of the vid:

Are you going to try the big bore kit next.

 

[Terry Syd]

If a big bore kit doesn't fix the problem, then it is likely an ignition issue. Changing carburetors didn't have any effect; so with compression, fuel and spark the main things to look at, it would likely be 'spark' that is the issue.

I'd still like to know what is causing the low compression. A squirt of heavier motor oil in the spark plug hole will seal the rings to get a decent compression if it is the rings not sealing right. If the oil doesn't bump up the compression, then it must be the design of the combustion chamber - either the piston deck height or the combustion chamber being too big.

My big bore needs the use of the de-comp valve in order to crank it over without flogging yourself to death.

 

[Czed]

If a big bore kit doesn't fix the problem, then it is likely an ignition issue. Changing carburetors didn't have any effect; so with compression, fuel and spark the main things to look at, it would likely be 'spark' that is the issue.

I'd still like to know what is causing the low compression. A squirt of heavier motor oil in the spark plug hole will seal the rings to get a decent compression if it is the rings not sealing right. If the oil doesn't bump up the compression, then it must be the design of the combustion chamber - either the piston deck height or the combustion chamber being too big.

My big bore needs the use of the de-comp valve in order to crank it over without flogging yourself to death.

Yes sir they are necessary with sweaty hands.
i nearly hit myself in the teeth with one of my big bore saws the wrap slipped out of my hand and the saw went flying.

 

[Czed]

I ordered a couple of cheap d ring handles and later on some oem decomps.
i just don't like the Chinese decomps.

 

[Czed]

I borrowed a gauge and mine are 150- 165 or so not great but fine.
i keep getting Inconsistent readings on my old blue point.

 

[Mattyo]

Of interest the flywheel is different from what I've seen from Farmertech. They are now using a cast in key. I'm wondering if somehow the timing is retarded.

Its possible i have a weak coil as well. Spark plug is brandy new NGK

But that doesn't explain the low comp...especially compared to others results.

 

[Czed]

Like this not the best but acceptable new big bore it will gain some after a few tanks.

 

[Czed]

Of interest the flywheel is different from what I've seen from Farmertech. They are now using a cast in key. I'm wondering if somehow the timing is retarded.

Its possible i have a weak coil as well. Spark plug is brandy new NGK

But that doesn't explain the low comp...especially compared to others results.

I did try to advance the timing on the first one and it was a dog slow to rev and gutless.

 

[Terry Syd]

Its possible i have a weak coil as well.

If you had a weak coil, it would most likely want to misfire when you put a load on it. If the coil is still able to fire when you put a strong load on it, then you may be right about the timing.

 

[Poleman]

Of interest here. My kit has the cast in flywheel..... it starts nice and idles but will NOT take throttle. I ground the key off and chased the timing from -30 to + 30 but still couldn't get it to take throttle.
First thing I did after initial start with the AM carb was put on a stock Zama...no change. I've checked fuel line, filter, changed the impulse line, checked to see in it was clear(it was). My only thoughts on it now would be the coil....just haven't truer a new one yet.
FRUSTRATING!!!!

 

[Czed]

Of interest here. My kit has the cast in flywheel..... it starts nice and idles but will NOT take throttle. I ground the key off and chased the timing from -30 to + 30 but still couldn't get it to take throttle.
First thing I did after initial start with the AM carb was put on a stock Zama...no change. I've checked fuel line, filter, changed the impulse line, checked to see in it was clear(it was). My only thoughts on it now would be the coil....just haven't truer a new one yet.
FRUSTRATING!!!!

One of the other guy's i spoke with has had several bad chinese coils but usually heat killed them.
I have an oem as backup but the chinese one's are fine
Hope you get it worked out
Did you get a tank yet.