Stihl 046

[bowpro73]

It's the original carburetor, and I have adjusted it, so to speak. If I choke it and pull until it fires over, and then move the switch off the choke, it won't start. It's immediately flooded. I can pull the plug, and it's wet already. Is this the low adjustment screw backed out too far? Seems to be intermittent. Last week, I diced up a whole hardwood trunk at a friend's. It ran like a champ. I bought a new log splitter today and tried to fire it up and got the crap symptom. Question for the carb gurus..... should I mess with a new rebuild kit, or just start with a new carburetor altogether? I've had it since the 90's. Just wondering if the carb bodies can get to a point where they just need to be replaced.

 

[Stump Shot]

Well, seeing as you had it that long I'd say for sure at minimum it could use a freshening with a rebuild kit, as the diaphragms can get hard, crack etc., as well as the inlet needle could fail letting too much fuel in. Yes, some vintage saws can have carb bodies that are warped and have a hard time sealing up once rebuilt. A bit tricky to fix this condition once found and replacement may be a better option and if so get one from Stihl or Walbro as the AM's can be a crap-shoot to get a good one. Replace the filter(large Stihl) and check the fuel and impulse lines while you're in there, if either too hard or too soft, replace with new from Stihl and a new spark plug and your saw should be back to running like it was 1999 again.

 

[Bob Hedgecutter]

Was going to let someone more local run with this- someone with E fuel experience as it seems to cause a lot of carb related issues I just do not get to experience here.
Excellent post above, factory carb kit would be my first port of call and factory settings of the adjustment screws after clean and rekit/rebuild.

But will also add- how old is the fuel mix?
Can you vac and pressure test the carb- the saw? If not can you get it running and spray brakeclean or similar around all the likely air leak places- like seals, gaskets and carb to cylinder manifold.
Check fuel line for air leaks, pin holes or cracks.

Will it always "pop" on full choke and are you moving the master control to fast idle or is it falling to "run" after initial pop?

 

[huskihl]

Check to make sure your master control lever is still holding the throttle open slightly in the high idle position

 

[Norm]

Check to make sure your master control lever is still holding the throttle open slightly in the high idle position

I second that

 

[Norm]

I would do all Steve said regardless.

Well, seeing as you had it that long I'd say for sure at minimum it could use a freshening with a rebuild kit, as the diaphragms can get hard, crack etc., as well as the inlet needle could fail letting too much fuel in. Yes, some vintage saws can have carb bodies that are warped and have a hard time sealing up once rebuilt. A bit tricky to fix this condition once found and replacement may be a better option and if so get one from Stihl or Walbro as the AM's can be a crap-shoot to get a good one. Replace the filter(large Stihl) and check the fuel and impulse lines while you're in there, if either too hard or too soft, replace with new from Stihl and a new spark plug and your saw should be back to running like it was 1999 again.

Totally agree carb kit fuel lines etc.