55psi with new piston???

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We've been this route already in the earlier posts. I don't see how this is the incorrect piston. It fits the bore snuggly, I cannot get a .015 feeler in between the cylinder wall and piston. The rings gap at .018. I have 125 psi compression.
 
Sounds like the bottom end of the saw might be flooded, remove plug and let air out. You might also check your carb settings, sounds like they might be a bit off. On some of these saws, it doesn't take much for them to not want to start if the carb is a bit off....

:cheers:
Mike
 
I say you have it flooded bad. Pull the plug tip it upside down,shake it drain it whatever to drain the gas out of it. Dry the plug and try again. Where are the needles set? Open too far maybe. 125 is probably normal for brand new ring that hasnt seated yet. I just put a Husky 51 together with a Taiwan ring and had 125 and it started on the 3rd pull. You are doing way too much at once. Slow down and take it easy. Although its kinda late to tell you that now. :cheers:
 
Where should I start with the settings. They have limiters on them. I put them in the middle. Would blowing compressed air into the plug hole help correct the lower end flood condition?
 
Compressed air would help. Turn saw upside down pull trigger to open butterfly and see if any gas comes out. You may also have a carb issue but we wount go there til you get it started. Turn the screws in all the way and see what happens.Against the limiter that is.:cheers:
 
bjorn773 said:
Where should I start with the settings. They have limiters on them. I put them in the middle. Would blowing compressed air into the plug hole help correct the lower end flood condition?
Click to expand...

Your saw should run pretty much anywhere within the limiter limits. Pull the plug, turn the saw upside down, pull the rope over several times to help clear any pooled fuel, and let it set for several hours. Then try to start it again.

Are you familiar with the procedure of starting a chainsaw? Put the saw on chake and fast idle. This varies by manufacturer how you do this. Pull the rope until you hear the engine "pop". Don't pull even one more time or you're likely to flood it. Switch the choke to off, but leave on fast idle. Pull the rope until then engine starts. Release the fast idle.
 
I turned in the carb screws against the limiters. I DO get fuel dripping out when I turn the saw upside down. I'll let it vent and try it later I guess.

I'm new to 2 strokes, spent my whole career working on cars. This is an entirely different animal. I appreciate everyone schooling me.
 
BTW, I pulled the flywheel. The key is cast into the flywheel and looks fine. I figured that was a longshot, but that's how we learn right? I've always been more of a hands on type, gotta see it for myself.
 
bjorn773 said:
I turned in the carb screws against the limiters. I DO get fuel dripping out when I turn the saw upside down. I'll let it vent and try it later I guess.

I'm new to 2 strokes, spent my whole career working on cars. This is an entirely different animal. I appreciate everyone schooling me.
Click to expand...

If it's flooded that badly, it won't hit a lick. Pull the rope over a few times to help clear it and then let it set with the spark plug out. Also, I would be more inclined to have the needles backed out against the stop. The saws are usually on the lean edge from the factory. I always remove the tabs on all of my saws though. That way I can put them where ever the saw needs them to be to run its best. You usually want to start 1-1 1/4 turns out from bottomed out.
 
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I'm familiar with starting a 2 stroke and adjusting the carb. This one is a bit in the gray because it's a new to me saw that was trashed and disassembled when I got it. I still don't know why it failed, haven't been able to get ahold of the owner. I understand the epa wants these things running as lean as possible. I do plan to cut the limiters. This is gonna be my porting guinea pig saw, so I figured I should get it running first. I'll cut with it a little so I have a basis for comparison after some porting and muffler mod. After all that, I can tackle the 365 and 385 I just bought.

Since it flooded at the half way point in the limiter, it seems logical to me to turn them in lean to start so I don't risk flooding again. Then once I get it started I can adjust. Yes or am I so green I'm talking out my...?
 
bjorn773 said:
Since it flooded at the half way point in the limiter, it seems logical to me to turn them in lean to start so I don't risk flooding again. Then once I get it started I can adjust. Yes or am I so green I'm talking out my...?
Click to expand...

If it was me at home, I would have held the saw WOT, no choke and started the SOB up......but I'm very impatient. I would also agree with Brad, back the screws out against the limiters too.

:cheers:
Mike
 
bjorn773 said:
I'm familiar with starting a 2 stroke and adjusting the carb. This one is a bit in the gray because it's a new to me saw that was trashed and disassembled when I got it. I still don't know why it failed, haven't been able to get ahold of the owner. I understand the epa wants these things running as lean as possible. I do plan to cut the limiters. This is gonna be my porting guinea pig saw, so I figured I should get it running first. I'll cut with it a little so I have a basis for comparison after some porting and muffler mod. After all that, I can tackle the 365 and 385 I just bought.

Since it flooded at the half way point in the limiter, it seems logical to me to turn them in lean to start so I don't risk flooding again. Then once I get it started I can adjust. Yes or am I so green I'm talking out my...?
Click to expand...

Your thinking right. Once its running you would probably want to bad them out.:cheers:
 
bjorn773 said:
I just installed a new piston into my 350 Husky. Before assembling it completely, I put the compression gauge in and pulled her over. I'm only registering 55-60 psi on the gauge. The comp release seems to be in the out position. I don't have a carb or exhaust on it, will that make any difference?
Click to expand...

Think you 'll need to attach muffler and carb to get accuate reading. Otherwise pressure will escape through intake and/or exhaust.
 
I wonder if I'm missing something. Individuals with a lot more experience than me haven't mentioned lack of muffler and carb installed, in this thread. Wouldn't these be necessary to get an accurate comp reading? I'd always assumed so.
Bob
 

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