I'm looking at the Stihl Series 4180 Powerhead Service manual dated 2005-12 that includes this FC-95 trimmer. Under valve adjustment is starts with the following: "Check and adjust valve clearances only when engine is cold". How did you figure-out that warming the engine prior to valve adjustment is required?
I've only ever done it when it was cold. Never heard it had to be warmed up. Maybe warming loosens the nuts or expands to make the proper gap? Who knows
Yes. If you are on the wrong stroke the rockers will move when you move the flywheel. If you are on the correct stroke the rockers will be loose as they are at the 3:10 video mark even if you move the flywheel a little bit.
Excellent MM1!! We get them in all the time saying hard to pull start. Adjust the valves, good to go. We do keep that set in stock from Stihl. I do it a little different, one closed and one open. Did you use 100:1 ratio? 😆🤣 Jeremy YOU ARE AWESOME !! Great job as always!!
Yeah I’ve done it with one closed one open. You have to be more precise and make sure you are on the base circle of the cam lobe. A few degrees either way and it’s starts to overlap the valves.
STIHL is good trimmer but more problems than Echo equipment that what I heard someone said that I don’t think that’s true. The Mower Medic one do you think that’s true? All equipment have problems
Yes Sir I agree. Echo equipment is top quality. Stihl is too but a bit more finicky & spendy. LOVE my new Echo MS-590 Timberwolf Chainsaw. Its a beast perfect Pro-sumer saw @ $399 great value
I know you've probably forgotten more than I'll ever know about these engines, but just a heads up, Stihl's service manual says to only check valve clearances when the engine is cold.
I have a Stihl HT101 polesaw. Is this the same procedure? It's got less than 30 hrs on it, but it runs rough & has very poor throttle response. The carb was rebuilt by a Stihl dealer (I had left it in the garage with fuel in it for about a year).
@@snoopfurlow1275 Spark arrester is clean as a whistle. I set the valve lash just like the video, fired it up & set the hi & lo jets. Unit runs like a scalded dog
Mechanics here in Miami hate those Stihl 4mix they always recommend us to buy Echos or Maruyamas cuz down here we put tons of hours a month on our equipment and valve adjustments had to be done every 2 months.
@@Plink-Plonk800 If it's a 4 stroke motor, which indeed it is, you will find one compression stroke for every 2 revolutions of the crankshaft. If it is a 2 stroke motor, then you should find a compression stroke for every revolution of the crankshaft. Check it yourself.... The reason the oil is mixed with the gas is the motor is operated in various positions relative to the direction of gravity. You can't rely on gravity to move crankcase oil to a sump pump like in a car engine or lawn mower engine which are only operated in one position relative to the direction of gravity. So distributing lubrication oil is done by mixing the oil with the gas and moving this mixture throughout the engine internals to distribute lubrication.
Why doesn’t anyone ever mention getting to cam lobe into the correct position? Shouldn’t you turn the engine and cycle the valve’s until TDC & arrow are on the correct stroke (tip of the cam lobe is down)?/?/? If you gap the rocker at .004 in between the intake and exhaust strokes then go 180* they will be stupid loose…. I’ve watched several videos and nobody ever mentions this…it’s not as easy as just “indexing the arrow to the ignition screw” because you can index it correctly on the wrong stroke…correct? Unless I’m doing something wrong….
You are vastly overthinking. There’s nothing to mention about the cam lobe. when you line up the flywheel arrow to the coil mounting screw on the compression stroke the cam is automatically put in the right position every single time. Did you even watch the video?
Not sure why they get all the hate. I have 12 years experience running these engines and they are beautiful torque monsters. Always only use premium gas, never that ethanol crap, and mix properly. No problems
Thanks for the refresher course. I have 2 4 mix engines i need to adjust the valves on in the next couple of weeks.
Hey guys here is the valve lash set I mentioned in the video
amzn.to/3wR5VMq
Very good explanation and video quality. TAL from Sevilla España.
I love mine it has tons more torque than a normal 2 stroke.
Had no idea you had to warm them
I'm looking at the Stihl Series 4180 Powerhead Service manual dated 2005-12 that includes this FC-95 trimmer. Under valve adjustment is starts with the following: "Check and adjust valve clearances only when engine is cold". How did you figure-out that warming the engine prior to valve adjustment is required?
I've only ever done it when it was cold. Never heard it had to be warmed up. Maybe warming loosens the nuts or expands to make the proper gap? Who knows
I have km91r hoping to get running
ótimo serviço..
Super tips as always
On the 4 mix do you have to be on the right stroke to adjust the valves
Yes. If you are on the wrong stroke the rockers will move when you move the flywheel. If you are on the correct stroke the rockers will be loose as they are at the 3:10 video mark even if you move the flywheel a little bit.
Excellent MM1!! We get them in all the time saying hard to pull start. Adjust the valves, good to go. We do keep that set in stock from Stihl. I do it a little different, one closed and one open. Did you use 100:1 ratio? 😆🤣 Jeremy YOU ARE AWESOME !! Great job as always!!
Yeah I’ve done it with one closed one open. You have to be more precise and make sure you are on the base circle of the cam lobe. A few degrees either way and it’s starts to overlap the valves.
Raleys What oil & ratio do you prefer since you don't like 100:1?
@@Mechanicalcircus 50:1 in everything
Does the kit work with a KM 90?
STIHL is good trimmer but more problems than Echo equipment that what I heard someone said that I don’t think that’s true. The Mower Medic one do you think that’s true? All equipment have problems
Yes Sir I agree.
Echo equipment is top quality. Stihl is too but a bit more finicky & spendy.
LOVE my new Echo MS-590 Timberwolf Chainsaw. Its a beast perfect Pro-sumer saw @ $399 great value
Where did you get the parts list. Is it from stihl or can you find it online. Great video once again
Thank you
www.diyspareparts.com/parts/stihl/diagrams/fs-90/
I work for a government entity and we get any manual we want pretty much
@@THEMOWERMEDIC1 that makes sense. Thank you for the link 👍
I know you've probably forgotten more than I'll ever know about these engines, but just a heads up, Stihl's service manual says to only check valve clearances when the engine is cold.
Yes, because when the metal heats up it expands, so if you adjust it hot and it cools off, it will be out of adjustment
I have a Stihl HT101 polesaw. Is this the same procedure? It's got less than 30 hrs on it, but it runs rough & has very poor throttle response. The carb was rebuilt by a Stihl dealer (I had left it in the garage with fuel in it for about a year).
Yes.and Check the muffler screen if its clogged it wont run full throttle..then try turning the hi,low screw on the carburetor.
@@snoopfurlow1275
Spark arrester is clean as a whistle. I set the valve lash just like the video, fired it up & set the hi & lo jets.
Unit runs like a scalded dog
Mechanics here in Miami hate those Stihl 4mix they always recommend us to buy Echos or Maruyamas cuz down here we put tons of hours a month on our equipment and valve adjustments had to be done every 2 months.
NOT a 10 thousands gauge! It is 0.1mm or .004 inch
Please whish is the gauge size ???? 1 mm ???
10 mm filler
gauge
@@Moncho68 It is 0.1mm or .004 inch
@@snoopfurlow1275 It is 0.1mm or .004 inch
Is it OK to eye ball lol
Please whish is the gauge size ????
10 millermeter gauge
Question how did you know that was an issue before you took it apart. Maybe I missed something I couldn't hear with my kids yelling lol
It’s not an issue. Just routine maintenance.
@@THEMOWERMEDIC1 is that only for weedeaters or all lawn equipment
@@jaimepadilla9548 2 stokes don’t have valves
@@THEMOWERMEDIC1 👍
Good job thanks
If this machine is 4 stroke, where does it get its lubrication from ?!
2 stroke I understand.
Where's the sump?!😢
You still mix the oil with the fuel.
It’s a 2 stroke with valves. Not a 4 cycle 👍🏼
@@Plink-Plonk800 If it's a 4 stroke motor, which indeed it is, you will find one compression stroke for every 2 revolutions of the crankshaft. If it is a 2 stroke motor, then you should find a compression stroke for every revolution of the crankshaft. Check it yourself.... The reason the oil is mixed with the gas is the motor is operated in various positions relative to the direction of gravity. You can't rely on gravity to move crankcase oil to a sump pump like in a car engine or lawn mower engine which are only operated in one position relative to the direction of gravity. So distributing lubrication oil is done by mixing the oil with the gas and moving this mixture throughout the engine internals to distribute lubrication.
Thanks
Why doesn’t anyone ever mention getting to cam lobe into the correct position? Shouldn’t you turn the engine and cycle the valve’s until TDC & arrow are on the correct stroke (tip of the cam lobe is down)?/?/? If you gap the rocker at .004 in between the intake and exhaust strokes then go 180* they will be stupid loose…. I’ve watched several videos and nobody ever mentions this…it’s not as easy as just “indexing the arrow to the ignition screw” because you can index it correctly on the wrong stroke…correct? Unless I’m doing something wrong….
You are vastly overthinking. There’s nothing to mention about the cam lobe. when you line up the flywheel arrow to the coil mounting screw on the compression stroke the cam is automatically put in the right position every single time. Did you even watch the video?
@@THEMOWERMEDIC1 Please whish is the gauge size ???? 1 mm ???
Smash the bell hahah. 🔔
Can t find value on 94k
Thats because the fs94/km94 is a 2 stroke. No valves
I highly recommend never buying a 4mix. The new ones (after 2015) are garbage
Not sure why they get all the hate. I have 12 years experience running these engines and they are beautiful torque monsters. Always only use premium gas, never that ethanol crap, and mix properly. No problems
It’s NOT A 4 CYCLE.!!! It’s a 2 stroke with valves.
Wrong it’s a four cycle engine through and through
Intake, compression, power, exhaust. That's 4
Those 4 mix engines are junk.Would never buy them.
Valve lash is always done cold