Stihl 041 AV FarmBoss No Fuel to Carb

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Sourwould

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So I picked up the old 041 I was looking at getting. It will run with a little fuel sprayed into the carb, but won't pick up fuel from the tank. Checked fuel line to carb, clear. Checked line from cylinder, good. Tried starting with the fuel cap off to see if the vent isn't working, nothing (the tank vent appears to be in the cap). Took the bottom plate off the carb to see if the pump diaphragm was torn, looks good. Very dry in the fuel pump area. The gasket looks like it's in good shape, but there's definitely not any fuel getting that far.

So hivemind, what is my next step? Carb kit?
 
Pulse line is good. Looks like someone replaced the pulse line, fuel line and filter. Probably trying to track down this same thing. I think I'm going to replace the gaskets at the carb and see if I've got a vacuum leak there.

How terrible are new carbs from sources like Amazon? At $17, seems hardly worth it to rebuild the carb with a $10 kit.
 
The gaskets at the carb are pretty dry and tired and need to be replaced, but would this cause the carb not to pick up fuel?
 
Plastic ketchup bottle from Walmart. Useful for applying pressure or vacuum to the carb or gas line.

Or, just bypass the tank and do a short run check.
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Came in handy to spot bad filters out of a batch.
 
Rebuilt the carb and replaced all the gaskets in the intake stack today. Most importantly, I noticed that the fuel line was running to the pulse port and the pulse line to the fuel inlet. Last guy in must have mixed them up. Started first pull.

Still have some fiddling to do. It's idling very fast and bogs at WOT. Maybe I've still got a vacuum leak. Maybe the carb needs adjusting. I've only had one go before at adjusting a Chainsaw carb and it didn't go well.

It's amazing how much louder this guy is than my old 026.

IMG_20180410_173243.jpg IMG_20180410_180442.jpg
 
Got a decent tune on this old saw at lunch today. Cut up some maple and oak when I got home. Love this saw. It's as much of a work out as swinging an axe, but man this thing screams. The super version must have been sweet. Makes rip cuts fairly easily, which is just what I need.
 
I got another bar for this 041. It's a hard nose, .063 gauge. The 041 has a .050 bar and chain on it now. Will switching the gauge of the bar and chain effect the sprocket in any way? It's the star style sprocket.
 
You can run any gauge chain on your spur sprocket. The only thing that might cause a problem would be if the sprocket is worn from the 50 gauge chain. The new 63 gauge bar will be a little bit wider so the bar groove will sit out a bit wider than the 50 gauge bar. If the sprocket has a groove worn in it from the 50 gauge chain then that groove wont line up with the 63 gauge bar and could cause excessive wear on your chain.
 
There's supposed to be a whole bunch more "stuff" in that area, which is why there are so many friggin gaskets on 041's. I'm going off memory (and coffee hasn't kicked in yet), but I seem to remember a black plastic shield thing and a metal cover that forms the bottom of what the air filter seals to. Maybe that metal part goes on top of the carb; can't remember. But I'm pretty sure that if you're looking at the lines, there's supposed to be some sort of shroud or cover or something that makes it where you can't see the cylinder. Of course, I'm not 100% sure that it matters, either. But one would have to be smart about how they configured the gaskets, and those stacks of gaskets are the #1 place where an 041 leaks (in my experience... only worked on 4 or 5 of them).
 
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