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3400 issue

countryhog

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Let me start by saying I hate HD- carbs.
Now, rebuilt this 3400 - carb, rings, lines, etc. deleted gasket and modded muffler. Starts well but loads up at WOT and commences with fluctuations in rpm at high rpm. also floods really easy.
Took the carb apart, soaked it again in solvent couple days, sprayed it liberally with brake cleaner, and adjusted the lever to couple hundredths below the recommended height.
Started it yesterday, revved it couple times and it still fluctuates. Shut it down. Tried to start it today. Naturally I engaged the choke. Big mistake. That thing flooded bad. Pulled the starter couple hundred times with throttle fully open. Sometimes it'll pop. I figure eventually it'll start.
<couple of days later>
New development. Gets curiouser. Rebuilt the carb again today. Tried to start it, no dice. Then put it on a known runner. Voila, started on first pull.
So now I have spark (plug out and grounded), fuel (wet plug), and air. I know the spark is not conclusive. Gonna swap coil with a known runner just for jollies.
Only other thing I can think of is I may have gapped the rings too wide. Had to file down a sxl set of rings.
This saw has never run consistently since the build. It's about to piss me off. Have no idea of compression but this thing has run with passion several times. Switch is good. As said, had good white spark today and it wouldn't start. Starting to see why this thing was laid aside before. Someone may get a good deal sometime
Anyone got any realistic thoughts on this?
 

skidooguy

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You have more patience than I do. I would have buried that thing by now.
 

d.l.d

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Had some of the issues stated and it was bad crank seals that held pressure but not vacuum. Saw flooded easily and fluctuated rpms a at times. I thought it was the carb because it never raced/ran lean as that is what i usually saw with bad seals. And had other saws with the same symptoms and it had been the carb. never could tune the carb though. It was a Chinese knock off and i had heard that some had gotten ones that wouldn't tune. So i tried one off a known runner and still had the problem. Then did a pressure/vac test and thats what it was. Probably should have done that first but didnt because it seemed like a carb problem. The saw also ran good at times.
 

backhoelover

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lol just so simple some times i have learned anything that touches my bench get a plug right after a compression test and removing the cylinder
 

backhoelover

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removing the muffler sorry trying to talk on two forums at once
 

countryhog

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The plug was new after the total disassembly and rebuild.
Yes it is a Champion
 
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