MS200t bogging/stalling on startup

[Nathan Graff]

So, lately, my MS200t has been bogging/ stalling on cold startup. It'll idle, but if the go switch is pressed too hard, it'll stall. It'll start first pull in the half choke position every time after it's started. After a min or 2 of playing around with reving and letting off as it bogs, it'll run full tilt with no problems. It'll start and run properly while it's still warm, but as soon as it cools off, it'll do the same thing again.

Anyone got any ideas as to the cause of the problem? So far, I've cleaned out the spark arrestor, and the air filter (but might get a new air filter anyways). No change.

 

[lone wolf]

So, lately, my MS200t has been bogging/ stalling on cold startup. It'll idle, but if the go switch is pressed too hard, it'll stall. It'll start first pull in the half choke position every time after it's started. After a min or 2 of playing around with reving and letting off as it bogs, it'll run full tilt with no problems. It'll start and run properly while it's still warm, but as soon as it cools off, it'll do the same thing again.

Anyone got any ideas as to the cause of the problem? So far, I've cleaned out the spark arrestor, and the air filter (but might get a new air filter anyways). No change.

Carb sure comes to mind. Check to see if the impulse line is disconnected or the fuel line is cracked .Fastest way to troubleshoot this would be to swap a known working carb.

 

[SEAM]

The very early ones had the old-type carb without accelerator pump, but the newer ones do. A worn accelerator piston will cause symptoms like that (e.g. no or poor acceleration)... not easy to repair satisfactorily, a carb replacement very often is the only fix. Could also be something else, though, like impulse line off/leaking, fuel line cracked, fuel filter clogged, etc.

 

[Nathan Graff]

Carb sure comes to mind. Check to see if the impulse line is disconnected or the fuel line is cracked .Fastest way to troubleshoot this would be to swap a known working carb.

Unfortunately, I don't have a known working carb. Any ways to vac/pressure test it?

 

[lone wolf]

Unfortunately, I don't have a known working carb. Any ways to vac/pressure test it?

It can still be bad even if it passes there are lots of things to go bad .
Did you check to see if the impulse line was tight and the fuel line looks good? If so its prob the carb you could send it here if you need help the carb that is. Try to borrow one off a friend maybe?

 

[Ketchup]

Could be a needle issue also. You tried turning the L out a tad?

 

[Nathan Graff]

It can still be bad even if it passes there are lots of things to go bad .
Did you check to see if the impulse line was tight and the fuel line looks good? If so its prob the carb you could send it here if you need help the carb that is. Try to borrow one off a friend maybe?

Truth be told, I'm the only one I know right now with a ms200/t. I haven't checked the lines yet.
Thx for your offer to look at the carb. I may just take you up on in.

 

[Nathan Graff]

Could be a needle issue also. You tried turning the L out a tad?

No, I'll give that a try.

 

[Mad Professor]

A classic symptom of low too lean, is bog off idle. Try ~1/8 out on low.

If it is a new symptom, as You mentioned , may be another underlying cause.

I also have saws that just don't run good unless you warm them up. I live with that as they are tuned well, warm and in a cut. Takes a couple minutes to warm up.

I always warm up engines regardless. Most of normal, wear, occurs during warm up. Air cooled until fins get warm/hot, water cooled when temp gauge starts to move.

 

[Chainsaw Jim]

You may have no option to troubleshoot without putting a new metering diaphragm in the carb. Also remove the spark screen to inspect for excessive build up.

 

[Mad Professor]

You may have no option to troubleshoot without putting a new metering diaphragm in the carb. Also remove the spark screen to inspect for excessive build up.

If you are careful usually can remove diaphragm without tearing it. While you are in there, check carb internal mesh screen/filter.

There was a good tip a while back to put a film of vasilene on carb gaskets/diaphragms and they come off without tearing.

 

[Nathan Graff]

A classic symptom of low too lean, is bog off idle. Try ~1/8 out on low.

If it is a new symptom, as You mentioned , may be another underlying cause.

I also have saws that just don't run good unless you warm them up. I live with that as they are tuned well, warm and in a cut. Takes a couple minutes to warm up.

I always warm up engines regardless. Most of normal, wear, occurs during warm up. Air cooled until fins get warm/hot, water cooled when temp gauge starts to move.

I generally warm anything with an engine up before actually using it. On the saws, I rev them a little bit to get them going, but don't cut anything for a min or 2.

 

[Nathan Graff]

An update, Today I started the saw, and no problems. Ran like normal.

 

[lone wolf]

An update, Today I started the saw, and no problems. Ran like normal.

I wonder if the gas caused it.

 

[Nathan Graff]

I wonder if the gas caused it.

I don't know. Been about 1/3 of a gallon coming from the same can in that saw, and I haven't finished the can yet. Maybe I should add a cap full or 2 of seafoam to the tank and run it, see if that fixes it.

I was thinking of muffler modding the saw. How big of a hole should I drill in the muffler? Do I drill the hole to the rear of the spark arrestor screen?

 

[Brent Nowell]

I wouldn’t run seafoam in it nathan, unlike a 4 stroke in which it can unstick a valve, clean a seat or clean out the intake that stuff don’t apply to a 2 stroke. The sea foam will hit all of the bearings and it could affect your burn causing detonation.
I personally just don’t think it’s wise

 

[cus_deluxe]

they have a rate of 2 oz per gallon of premix for 2 stroke right on the can? ive used it lots on 2 strokes, even had it turn non runners into runners after a couple weeks of sitting in the carb.

 

[siouxindian]

this proly something i can say that happen to me. i got a ms 180 brand new from a friend never had gas or bar lube in it. sonsofbitches would run good through a couple tanks of gas then give me lots grief then run good.i started using red armor oil never gave me 1 problem after a few tanks of red armor. proly a carb kit would have fix mine but may be a carb replacement would fix this 1 you got. if you give up send it to lonewolf.

 

[stilh036prohog]

Pull the muffler off and clean it. Any built up will cause your problem.

 

[lone wolf]

I don't know. Been about 1/3 of a gallon coming from the same can in that saw, and I haven't finished the can yet. Maybe I should add a cap full or 2 of seafoam to the tank and run it, see if that fixes it.

I was thinking of muffler modding the saw. How big of a hole should I drill in the muffler? Do I drill the hole to the rear of the spark arrestor screen?

Leave the muffler alone! Just pull out the screen and it will gain about 1 second in a 10 inch cut.