Stihl MS200 problems
- Thread starter Lowhog
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Ordered a new carb from feebay for 11 bucks and change. Hopefully that will do the trick.
Chashowlett
ArboristSite Operative
The manual says if adjustment's don't fix then do a vacuum test,
My impression is it's not a carb issue . Accelerator pump will just sputter if bad. Bogs are usually a seal/bearing, or cylinder issue. Good hunting
My impression is it's not a carb issue . Accelerator pump will just sputter if bad. Bogs are usually a seal/bearing, or cylinder issue. Good hunting
Accelerator pump... if the pump piston cannot move freely any more to provide extra fuel during acceleration the engine will stall. Saws used with a faulty accelerator pump over an extended period of time tend to develop signs of (engine) seizure.
Compression is good. I will order the fitting I need for a vacuum test like you say a vacuum leak is what I suspect also. impulse line and carb boot are in good shape.
cus_deluxe
Commie Satan turd
This.
hangfirew8
ArboristSite Operative
Cheap clone carbs can be more trouble then they're worth. That being said, some of the original carbs on this model are infamous for the accelerator pump issue. Much was discussed in this thread but not everything suggested there was a good idea (blocking pump means temp lean condition). But it is an educational thread.
I've had one for several years. But mainly I am only an expert on what doesn't work.
The blocking of the pump only means that the L screw (+ idle speed screw) will have to be adjusted to richen up the mix after the conversion. If too lean the engine will not accelerate properly.
The accelerator pump most probably was implemented for EPA reasons (reducing harmful exhaust gases during idling)...
The very first MS200 still had a conventional carb - the same carb as used on the 020. That carb will be fine as well.
Chashowlett
ArboristSite Operative
Take the carb off and pressurize the inlet fuel port to 10lbs psi and dunk the carb in soapy water and look for bubbles. If you see bubbles around the throttle shaft or coming out the front then the acc. pump is leaking/faulty, doubtful, you can see if your carb is holding pressure first. Walbro site has an excellent video on how to troubleshoot a carb
Its not a clone carb its the same carb that on the saw a Zama.
Did you check the fuel filter for clogging and the fuel line for cracks? And the piston for scoring? The carb can deliver fuel only if the peripherals are in good working order.
Also, air leaks can occur in a number of forms: crank seals, fuel line, impulse line, loose spark plug, gaskets (also in the carburetor), etc. etc.
If you have the means to pressure test the crankcase you can start there - and also check all the parts that have to be removed for this purpose...
Also, air leaks can occur in a number of forms: crank seals, fuel line, impulse line, loose spark plug, gaskets (also in the carburetor), etc. etc.
If you have the means to pressure test the crankcase you can start there - and also check all the parts that have to be removed for this purpose...
Lee@themancave
ArboristSite Lurker
Possible engine air leak?
Sent from my SAMSUNG-SM-J120A using Tapatalk
Sent from my SAMSUNG-SM-J120A using Tapatalk
Yes.
