carb rebuild

[314epw]

Have 2 saws 362xpg,372xp.One saw was running bad when it warmed up. Ran rich on the low side.If I turned up the idle It would run,but not perfect.High speed OK.Switched carbs.Now the bad saw ran good and the good saw ran bad.

Rebuild the carb(Walbro HD 12)with a k10 kit.New gaskets,needle and seat etc.Still runs like crap.Never had a bad rebuild before.could it be bad needle valves.Those I haven't switched out.Or should I just bite the bullet and spend the $70.00 for a new carb?I just hate to surrender!
Ed

 

[HiOctane]

Can you pressure your carb to see if your needle is not leaking?Another thing,check if the welch plug is not leaking a bit,it gives the symptom you are describing.

 

[314epw]

Can you explain welsh plug to me please.I am not understanding.
Ed

 

[HiOctane]

Can you explain welsh plug to me please.I am not understanding.
Ed

Thats the round plug close to your main jet inside your carb.To check it ,put a bit of oil over the plug.Remove your needles and blow air(not too strong)in the hole of the lo speed needle.If the plug is leaking,you will see bubbles around the plug,you hae to replace it(be careful if you do)or just tap it a bit to "flatten" a bit more .Then you recheck if you still got bubbles.

 

[PES+]

If you find

If you find a sealent that works for the new gas formulations please let me know

Nail polish and laquers don't work any more

 

[Lakeside53]

I don't use any sealant on the welch plugs - the zama sealants (just a from of loctite) from the early 2000's are always flaking of and messing the carbs.

Stihl handed out a lot of warranty carbs due to plug sealant issues with "newer" gas, and now just advised "dry" and slight deformation.

 

[Lakeside53]

ED - your check valve(s) could be messed up and leaking. "Carb cleaner" and high flow compressed air can screw with the flapper material. The high speed is replaceable for a few $ (just presses in). If your carb has a low speed check valve, they are not replaceable...