Stihl MS200T replacement piston

[Treetom15]

I replaced the pot and piston on my 200t about 18 months/2years ago, it’s a cracking saw but it feels quite low on compression, and recently I’ve noticed it bog down on quite small stuff. I deleted the head gasket about a year ago, and when I had the saw in bits I noticed the piston was black down one side, like it was allowing gas past? Anyway, I’m going to strip the saw down and (probably) change the piston, just checking if anyone has any aftermarket recommendations? I’ve heard of Meteor pistons but can’t find them in the uk? @spud I’ve heard you may be the man to ask?

[spudulike]

You have probably replaced the pot and piston with something costing £20 so now have a saw with low compression and is just not very good.

You should have cleaned the existing OEM bore and fitted a Meteor piston and if you still have the cylinder, try it but you may have to get the piston in from Greece if GHS haven't got any.

Other than that, just fit a new OEM kit, they are around £85 and are the best option to get a tired 200 back up to full tilt! The Meteor kit is good but isn't much cheaper than the OEM one hence I only use the OEM cylinder kit now.

[Mark_Skyland]

OEM is a really good price on this machine(and the 201), pity every other pro saw be it husky or stihl is usually the best part of £200+

[Treetom15]

19 hours ago, spudulike said:

You have probably replaced the pot and piston with something costing £20 so now have a saw with low compression and is just not very good.

You should have cleaned the existing OEM bore and fitted a Meteor piston and if you still have the cylinder, try it but you may have to get the piston in from Greece if GHS haven't got any.

Other than that, just fit a new OEM kit, they are around £85 and are the best option to get a tired 200 back up to full tilt! The Meteor kit is good but isn't much cheaper than the OEM one hence I only use the OEM cylinder kit now.

Nope, was a genuine stihl pot & piston kit from L&S engineers, unless they sell knock off stuff? Where do you usually buy parts etc from, l&s have always been my go-to, but this saw doesn’t seem right. Cheers mate ?

[billpierce]

Nope, was a genuine stihl pot & piston kit from L&S engineers, unless they sell knock off stuff? Where do you usually buy parts etc from, l&s have always been my go-to, but this saw doesn’t seem right. Cheers mate [emoji106]

Depends which one you bought seems they sell genuine 80quid ones and non genuine ones. Either way worth doing a vac/pressure check when changing as you may have an airleak causing it to run lean. Why did it sieze the first time?

[Treetom15]

56 minutes ago, billpierce said:

1 hour ago, Treetom15 said:

Nope, was a genuine stihl pot & piston kit from L&S engineers, unless they sell knock off stuff? Where do you usually buy parts etc from, l&s have always been my go-to, but this saw doesn’t seem right. Cheers mate

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Depends which one you bought seems they sell genuine 80quid ones and non genuine ones. Either way worth doing a vac/pressure check when changing as you may have an airleak causing it to run lean. Why did it sieze the first time?

It all came in stihl packing but I suppose that could be duff. It seized because the lad I got it off snapped the air filter screw and it fell thru the carb into the barrel?‍♂️ 

[Treetom15]

@spudulike this is the pot off the saw, does it appear to be a gen stihl product?

[spudulike]

That is original and L&S sell OEM ORIGINAL equipment plus a few AM spares but are a good supplier as I am a long standing customer or so they tell me

An original OEM top end with no gasket will give 200psi+ and you will KNOW it has good compression when you pull it over.

Have you measured the compression? has the kit been fitted correctly, was the piston the correct way round? Very strange that the OEM part isn't giving decent compression, I have never known it and have fitted a fair number? They usually last 10 years +.....have you measured the ring end gaps, were the circlips fitted correctly, any signs of wear to the piston or cylinder, was the air filter in good condition?

[Treetom15]

12 hours ago, spudulike said:

That is original and L&S sell OEM ORIGINAL equipment plus a few AM spares but are a good supplier as I am a long standing customer or so they tell me

An original OEM top end with no gasket will give 200psi+ and you will KNOW it has good compression when you pull it over.

Have you measured the compression? has the kit been fitted correctly, was the piston the correct way round? Very strange that the OEM part isn't giving decent compression, I have never known it and have fitted a fair number? They usually last 10 years +.....have you measured the ring end gaps, were the circlips fitted correctly, any signs of wear to the piston or cylinder, was the air filter in good condition?

I haven’t measured the compression, unfortunately I haven’t got the kit to hand to do this, I say “low compression”

as it felt easy to pull over and didn’t take a great deal to bog down whilst cutting. Arrow on the piston was pointing to the exhaust port (which I think is correct?) there is signs of wear to the piston, very slight marking on the barrel but I think that’s probably ok? The only thing I HAVE noticed, is when I stripped it down, both crank seals were “wet” and once I cracked the crankcase I noticed slight wear on the crankshaft where the seals sit-not sure if pulling air through there would result in low comp? Spark plug was a “biscuit brown” so wouldn’t appear to be too lean?