Husqvarna saw has me stumped

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Update, it seems like it was the carb. I pulled it off and blew it out with compressed air, idles and runs fine now. I still need to get it perfectly dialed in, but somehow the brand new carb must have gotten plugged. Who knows how, but glad I've got it working now. Thanks again for all the advice here.
 
Update, it seems like it was the carb. I pulled it off and blew it out with compressed air, idles and runs fine now. I still need to get it perfectly dialed in, but somehow the brand new carb must have gotten plugged. Who knows how, but glad I've got it working now. Thanks again for all the advice here.
Glad you got it sorted, I'd say you had/have crud in the fuel tank... I had a 460 recently that wouldn't run due to a leaky primer.
FWIW, it's not usually a good idea to blow compressed air through the carbs, there's a check valve in the main nozzle that doesn't tend to like it
 
Glad you got it sorted, I'd say you had/have crud in the fuel tank... I had a 460 recently that wouldn't run due to a leaky primer.
FWIW, it's not usually a good idea to blow compressed air through the carbs, there's a check valve in the main nozzle that doesn't tend to like it
Good to know on the compressed air, thanks. Out of curiosity, just so I understand, how/why would a leaking primer keep it from running? I though that was just for getting it started
 
Good to know on the compressed air, thanks. Out of curiosity, just so I understand, how/why would a leaking primer keep it from running? I though that was just for getting it started
It introduces an air leak into the fuel system causing the carb to draw less or no fuel. The valve's going in the primers can cause issues too.
Your correct in that the primer is just to make starting easier. It can be done away with completely... however, the lines must be properly sealed for that to work & the saw will usually take a few more pulls to start
 
It introduces an air leak into the fuel system causing the carb to draw less or no fuel. The valve's going in the primers can cause issues too.
Your correct in that the primer is just to make starting easier. It can be done away with completely... however, the lines must be properly sealed for that to work & the saw will usually take a few more pulls to start
Makes sense. Thanks for the info!
 
2 1/2 turn out on hi sounds excessive but if aftermarket who knows?I had a Huztl 372 carb that liked 1/2 turn out on the hi side.
I haven’t seen an actual physical shop manual, but I found what someone said was copied from the shop manual saying that was the stock setting for this saw. I actually have it a bit further out than that. While it now runs well, I do think there might still be a tiny leak somewhere between the carb and cylinder as it does seem that it needs to be adjusted rich to run well. The intake manifold does not seem to have any cracks or tears, but the plastic piece between the carb and rubber manifold looks like it could be slightly warped. It was only $15 so I ordered one to try and see if that improves things and allows it to run well without the screw out so far.
 
Over half a century of fettling 2 and 4 stroke cars, motorcycles, mowers DID NOT prepare me for chainsaw carbies :)
No motorcycle carb was ever made to function in all orientations such as sideways and upside down. You must pay attention to the impulse feed system and take particular care setting up the metering lever system. Other pitfalls are kinks in the fuel hoses. Getting the spark timing right is another possible problem, loose or sheared flywheel keys, and a bad or poorly functioning coil can have you tearing out your hair.

Good luck.
Damn good advice right there now. :)
 
Thanks in advance for any advice here - I have a Husqvarna 460 rancher that won't start. First of all, I know I could've easily gotten a working saw for what I've spent on parts here. But I like fixing things and keeping things out of the landfill (and honestly I didn't think i'd get in this deep when I started the project.

I got this saw very cheap in "used to run but sat a while" condition. Super dirty but otherwise complete. I have replaced what I feel like is every part, and it still won't work. Here's what I've replaced, all with OEM parts:

Cylinder and piston, and gaskets. The body of the saw is actually a 455 Rancher, I put on a 460 cylinder and piston. But from what I've read that shouldn't matter.
Carb
spark plug, air filter, fuel filter
Fuel Line
Crank seals
Compression release valve
Impulse line
Muffler (used OEM, not clogged)

The saw ran, briefly. I got like three or four cuts out of it. But now, after lots of pulling, the saw will fire for like a half second and then immediately die. It passes a cylinder pressure test easily (went from 0.8 to 0.75 Bar in 30 seconds, pressure or vacuum), has great compression.

I took the limiter caps off the new carb and set them to what I believe to be factory settings (1.5 turns out on Low, 2.5 turns out on high). I don't really know where to start the idle adjustment, but I've tried everything.

Any ideas? I really don't know where to go from here. Again, all OEM parts. I am fairly new to small two strokes but I am very mechanically inclined, former professional bicycle mechanic, have succesfully rebuilt motorcycle carbs, etc.

Again, thanks in advance for any advice.
Used OEM muffler (But not clogged) How do you know that? It doesn't take much to clog a muffler. Poor exhaust flow will cause too much back pressure and will definitely cause a no start. One indication would be a crankcase with excess fuel. I would remove the muffler and soak in carburetor cleaner. Not sonic cleaner method. Carburetor cleaner dissolves carbon. IMHO
Let us know what you find. OT
 
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