ms200t air leak?

[spudulike]

A vacuum/leakdown check will tell you if the crankseals have failed or are beginning to fail. A pressure check will do this also but is prehaps slightly less accurate as the vac test pulls the seals away from the shaft they sit on a little and they will leak if their seal has gone.

 

I know many can't do this check but any saw that comes in for a good look over gets this treatment, it may take a little while to do it but has found problems no one would have ever found with just a visual check - the way I see it is that this is what a customer pays for and I do it for peace of mind.

 

Funnily enough, I have never had an MS200/020T with faulty seals - some older saws on the clutch side have failed though!

[Al Smith]

I agree it's rather odd for the seals to fail .As it was though both those saws had the same problems most people report about over the internet .Running out lean after about a minute or less on start up .

 

It has been the assumption by many including myself thet the fault was with the Zama carbs .

 

I actually discovered this seal deal after having changed carbs using a known good one to test one of these offending saws .More or less it was just blind luck that I came upon it .Now this is not to say that every 200T that runs badly that the seals are the problem .However it very well may be that a percentage of high hour saws suffer from bad seals .

 

If you look at E-bay US there often is many 020T and 200T crankcases for sale rather reasonably priced .That factor indicates to me that air leaks from whatever cause has ruined a lot of these high priced little saws .

 

As of yet noone I'm aware of makes an after market cylinder and piston for these things and rebuild with OEM parts would be over half the cost of a new saw .

[3dogs]

Problem solved. pressure check done and all fine:thumbup1: stripped saw down to check the boot and looked all fine. When i put the carb back on i noticed the rubber pipe from carb into air filter was split so replaced just as a formality not thinking it would be the cause, and hey presto. Saw fires and runs a treat Thanks guys for your info:thumbup1:

[spudulike]

Problem solved. pressure check done and all fine:thumbup1: stripped saw down to check the boot and looked all fine. When i put the carb back on i noticed the rubber pipe from carb into air filter was split so replaced just as a formality not thinking it would be the cause, and hey presto. Saw fires and runs a treat Thanks guys for your info:thumbup1:

 

Its that bloody impulse line again - found one on the one I had on my "Whats on your bench" thread last week - got pictures of it on the thread if anyones interested.

 

The pressure check comes through again again:thumbup:

[3dogs]

always intrested:thumbup1:

[Al Smith]

Now that's a little confusing .The impulse line attachs through the boot as the carb impulse on a 200t does not use a seperate line like some do which goes on the fuel pump diaphragm side .

 

The little fitting that goes from the main diaphragm chamber to the air filter is the compensation device which regulates the amount of air the atmospheic side of the diaphragm gets depending on how plugged up the air filter is .It allows the saw to run at reduced power level until the air filter can be properly serviced ."intellicarb"

 

Now if that it what is discussed they should run without it . About the only thing you'll get is eventually the atmospheric side of the diaphragm will fill up with fine saw dust and the saw will run extrememly rich if the filter is plugged plus with an open hole in the back of the air filter box probabley suck in some fine dust that won't do the engine any good .

[GardenKit]

Now that's a little confusing .The impulse line attachs through the boot as the carb impulse on a 200t does not use a seperate line like some do which goes on the fuel pump diaphragm side .

 

The little fitting that goes from the main diaphragm chamber to the air filter is the compensation device which regulates the amount of air the atmospheic side of the diaphragm gets depending on how plugged up the air filter is .It allows the saw to run at reduced power level until the air filter can be properly serviced ."intellicarb"

 

Now if that it what is discussed they should run without it . About the only thing you'll get is eventually the atmospheric side of the diaphragm will fill up with fine saw dust and the saw will run extrememly rich if the filter is plugged plus with an open hole in the back of the air filter box probabley suck in some fine dust that won't do the engine any good .

I think the OP probably meant the impulse line, as there is no tube which attaches from air filter to carb as we know. There is however an impulse tube which attaches from the crankcase to the handle casing and is sealed by the flange of the boot to the carb.

[3dogs]

The little fitting that goes from the main diaphragm chamber to the air filter is the compensation device which regulates the amount of air the atmospheic side of the diaphragm gets depending on how plugged up the air filter is .It allows the saw to run at reduced power level until the air filter can be properly serviced ."intellicarb"

 

Thats the one!!!

 

Anyway fired the saw this morning and left it ticking over for good ten minutes and no problem:thumbup:, however thought id just try it again before locking up and it seems im back to square one:thumbdown:, saw would'nt start at all unless i held full throtle and then ran as if choke was on. More investigation needed i think:001_rolleyes:

[Al Smith]

That being the case it's flooding itself I would guess .Caused by ethanol in the gasoline ,petrol if you prefer. Then again I thought all you nice people had fuel that was better than the garbage we are plauged with .The ethanol causes the innards of the carb to stiffen up like cardboard after a few years .

 

Now I have no idea if the 200T's on that side of the pond are different or not from ours .However the main difference between an 020T and a 200T is the 200 will have the "intellicarb " thing and the 020 will not plus the 200 has flip caps ,the 020 has screw caps .Some 020Ts' had a fixed main jet carb ,a few .I've never seen a fixed main jet on a 200T .

[3dogs]

That being the case it's flooding itself I would guess .Caused by ethanol in the gasoline ,petrol if you prefer. Then again I thought all you nice people had fuel that was better than the garbage we are plauged with .The ethanol causes the innards of the carb to stiffen up like cardboard after a few years .

 

Now I have no idea if the 200T's on that side of the pond are different or not from ours .However the main difference between an 020T and a 200T is the 200 will have the "intellicarb " thing and the 020 will not plus the 200 has flip caps ,the 020 has screw caps .Some 020Ts' had a fixed main jet carb ,a few .I've never seen a fixed main jet on a 200T .

 

diaphrams are all good tryed both a spare carb and original and its the same prob.