Flippy Cap Blues

[sloch24]

Last year (spring I think) I put my saws away, and I haven't used them since. I cleaned them all up, ran them out of fuel, and filled the bar oil tanks. Every one of them that has flippy caps lost a significant amount of bar oil. My 260 is empty, my 440 is 1/2 empty, and my 460 dribbled a little.

Meanwhile, my 031, and my 660 are still full and the outside is nice and clean.

Do the O-rings need to be replaced on these caps every once in a while? I have always liked the flippy caps for ease of use, but this is ridiculous. I guess I won't be storing them full anymore.

 

[jeeptj19992001]

a new cap can be had for around 7 dollars, why dont you splurge on some new ones diamond jim brady

 

[oscar4883]

IMO just leave the oil tank empty and be done with it. Modern technology them caps. lol

 

[CT_TreeGuy]

O-ring info

a new cap can be had for around 7 dollars, why dont you splurge on some new ones diamond jim brady

Or:

Instead of implying that the asker is a cheapskate, and not even attempting to answer his question, like maybe sharing any experience you might personally have about the o-rings going bad, you might have gone with something like this:

I've never been a big fan of the flippy tops (too clever by half as I like to say), I suppose that once one learns to think like a flippy top, there's a remote chance that they can actually be properly closed with reasonable success on something approaching a consistent basis.

Quirks aside, it stands to reason that the o-rings might just start to lose their effectiveness after a while, and might just be good candidates for replacement. It's also possible that a replacement o-ring might actually be of higher quality than the stock ones. Many manufacturers use, and a lot of hardware stores stock, "Buna-N", which isn't particularly good at anything except being inexpensive. Viton is exceptionally good at standing up to petroleum-based products like the oil and gas we run in our saws. Are the stock o-rings viton? Well who knows? And who really cares, since viton o-rings are so readily available from a wide variety of sources, and probably for a whole lot cheaper than you could get stock ones from Stihl for, if they sell the o-ring separately at all.

So the OP got me thinking, and I took the cap off of my 460 and checked out the caps and o-rings. Right off the bat, the o-rings are totally normal, off-the shelf o-rings, and the caps seem to be interchangeable, with the o-rings exactly the same size. Hell, of a start, I say to myself.

Measuring up both the caps and the o-rings, I make them out to be Dash 214, which has a fractional size of 1" ID x 1.25" OD, and an actual size of 0.984" x 1.262". This sorts well with the measurements I took of the cap (about 1.10" diameter where the o-ring sits), and of the o-rings themselves, which were about 1.01" ID and 1.28" OD (after being in service for about 3 years).

They actually seem to be in pretty good shape; still plenty pliable, not torn, and still fairly round; but could they stand to be replaced with something that might be a little closer to stock specs, and maybe a superior material too as an added bonus?

On closer inspection, the average wall thickness of my used o-rings was about .1315". They were a bit flattened - .1350" high, and 1280 thousandths wide (I would have expected them to be flattened the other way), but replacing them with new o-rings would give me a good .070" tighter seal (((1.262" - .984")/2 - .1315) = .070)), so what the hell, I'm going to replace them.

Plenty of places to buy them
As so often happens when looking into something, I learned something new. There's a material called PTFE (polytetrafluoroethylene - oh yeah, Teflon, of course) that might be even better than viton for our purposes.

Teflon vs. viton:

hydrocarbon resistance: Viton good, teflon excellent
water resistance: Viton poor, teflon excellent
tearing: Viton fair, teflon excellent
abrasion: Viton good, teflon excellent
compression set: Viton good, teflon fair

This last one, compression set (how well does it spring back to its original shape after being compressed) might actaully be an advantage.

"Because of its chemical inertness, PTFE cannot be cross-linked like an elastomer. Therefore, it has no "memory" and is subject to creep. This is advantageous when used as a seal, because the material creeps a small amount to conform to the mating surface. However, to keep the seal from creeping too much, fillers are used, which can also improve wear resistance and reduce friction".

Polytetrafluoroethylene - Wikipedia, the free encyclopedia

Hmm, creeps a small amount to conform to the mating surface. Just might be what the doctor ordered.



Hey, did you know:

"The coefficient of friction of plastics is usually measured against polished steel. PTFE's coefficient of friction is 0.05 to 0.10, which is the third-lowest of any known solid material (BAM being the first, with a coefficient of friction of 0.02; diamond-like carbon being second-lowest at 0.05). PTFE's resistance to van der Waals forces means that it is the only known surface to which a gecko cannot stick".

Polytetrafluoroethylene - Wikipedia, the free encyclopedia

I bet you didn't. Take that, Mr. Gecko.

Oh, and what is "BAM"? I had no idea.

"BAM is a ceramic alloy created from an alloy of boron, aluminium and magnesium (AlMgB14) and titanium boride (TiB2). It is one of the hardest known materials, after diamond and cubic boron nitride. It is also the slipperiest solid known, with a coefficient of friction of 0.02; for comparison, Teflon products have coefficients of friction (dynamic) of approximately 0.04. The material was discovered in the course of other investigations by Bruce Cook and Iowa State University professor Alan Russell in 1999 at the U.S. Department of Energy's Ames Laboratory. "Its hardness was discovered by accident. We had a terrible time cutting it, grinding it, or polishing it," said Russell".

http://en.wikipedia.org/wiki/BAM_(material)

Hope this answers your question.

Best regards, John D.

 

[DSS]

a new cap can be had for around 7 dollars, why dont you splurge on some new ones diamond jim brady

Now there's a helpful post.:bang:

A new chain is only $15, let's just throw the old one away when it's dull.

You know, if we were really smart, we could just JB weld those flippy caps on when the saw is new, and when it runs out of gas, toss it and buy another one.

Then you wouldn't have to worry about the POS leaking all over your new pants, thus causing you to throw them away as well.opcorn:

A flippy cap is an over engineered piece of german garbage designed to fix a problem that didn't exist.

 

[J.W Younger]

I have no problems with the flip design, that said I did have a problem with leaks at both caps on a saw not used for a couple of years. O-rings replaced and caps stihl leaking..continued use and leaks stopped and have not returned after over 2 years use. Still scratching my head over the reason, seemed allmost like the leaks were in the lever mechanisms, if thats even possible...

 

[jus2fat]

Last year (spring I think) I put my saws away, and I haven't used them since. I cleaned them all up, ran them out of fuel, and filled the bar oil tanks. Every one of them that has flippy caps lost a significant amount of bar oil. My 260 is empty, my 440 is 1/2 empty, and my 460 dribbled a little.

Meanwhile, my 031, and my 660 are still full and the outside is nice and clean.

Do the O-rings need to be replaced on these caps every once in a while? I have always liked the flippy caps for ease of use, but this is ridiculous. I guess I won't be storing them full anymore.

Well first off...I don't understand why you thought filling the oil tank up for storage was a good idea?? Just curious!!

Second what makes you think the oil leaked from the flip cap??
(my saws leak--if oil left in tank--but they leak at the bar oil hole)
I either drain mine out (for storage) or just lean the saw over to the side of starter cover...no leak. Lots of folks have this problem.

You shouldn't need to change the O-ring--unless damaged- but I highly doubt that all these saws could have damaged O-ring.

I've only had one flip cap that leaked--(and also the oil cap)--my problem was the two parts that make up the cap--(one black and the other white) one of them had cracked--no way to fix.
I replaced the cap--about $8-- and no more leaky cap--just the bar hole leak.

Hope this helps...

J2F

 

[TK]

I never did like those caps. Not sure why, just don't.

 

[Storm56]

It is not a matter of IF you are going to have an issue with the flippy but WHEN.

 

[fidiro]

So far I have not read an answer to your question here. Just some flippy cap haters with no help for you. No matter how much one hates these caps bashing them more will not make them go away from the saws that are being used out there.

If it was my saw I would clean the tank out with some diesel fuel(if you have access to a small amount). Clean the cap as well first and blow it all out if possible to make sure everything is completely clean including removing the O-Ring to make sure it gets clean under it and reinstall same ring. One little grain of sand can cause the ring not to seat. If it still leaked after a really good scrubbing I would go ahead and get the O-ring next. I would go for the complete cap last and just save the new O-ring for another day. my 440 is leaking from the oil cap as well and that is what it is going to get to try and stop it.

Hope that at least the post about not leaving the oil in the tank can help in the future as there was a point that oil will leak through the bar oil hole.

 

[DSS]

Or:

Instead of implying that the asker is a cheapskate, and not even attempting to answer his question, like maybe sharing any experience you might personally have about the o-rings going bad, you might have gone with something like this:

I've never been a big fan of the flippy tops (too clever by half as I like to say), I suppose that once one learns to think like a flippy top, there's a remote chance that they can actually be properly closed with reasonable success on something approaching a consistent basis.

Quirks aside, it stands to reason that the o-rings might just start to lose their effectiveness after a while, and might just be good candidates for replacement. It's also possible that a replacement o-ring might actually be of higher quality than the stock ones. Many manufacturers use, and a lot of hardware stores stock, "Buna-N", which isn't particularly good at anything except being inexpensive. Viton is exceptionally good at standing up to petroleum-based products like the oil and gas we run in our saws. Are the stock o-rings viton? Well who knows? And who really cares, since viton o-rings are so readily available from a wide variety of sources, and probably for a whole lot cheaper than you could get stock ones from Stihl for, if they sell the o-ring separately at all.

So the OP got me thinking, and I took the cap off of my 460 and checked out the caps and o-rings. Right off the bat, the o-rings are totally normal, off-the shelf o-rings, and the caps seem to be interchangeable, with the o-rings exactly the same size. Hell, of a start, I say to myself.

Measuring up both the caps and the o-rings, I make them out to be Dash 214, which has a fractional size of 1" ID x 1.25" OD, and an actual size of 0.984" x 1.262". This sorts well with the measurements I took of the cap (about 1.10" diameter where the o-ring sits), and of the o-rings themselves, which were about 1.01" ID and 1.28" OD (after being in service for about 3 years).

They actually seem to be in pretty good shape; still plenty pliable, not torn, and still fairly round; but could they stand to be replaced with something that might be a little closer to stock specs, and maybe a superior material too as an added bonus?

On closer inspection, the average wall thickness of my used o-rings was about .1315". They were a bit flattened - .1350" high, and 1280 thousandths wide (I would have expected them to be flattened the other way), but replacing them with new o-rings would give me a good .070" tighter seal (((1.262" - .984")/2 - .1315) = .070)), so what the hell, I'm going to replace them.

Plenty of places to buy them
As so often happens when looking into something, I learned something new. There's a material called PTFE (polytetrafluoroethylene - oh yeah, Teflon, of course) that might be even better than viton for our purposes.

Teflon vs. viton:

hydrocarbon resistance: Viton good, teflon excellent
water resistance: Viton poor, teflon excellent
tearing: Viton fair, teflon excellent
abrasion: Viton good, teflon excellent
compression set: Viton good, teflon fair

This last one, compression set (how well does it spring back to its original shape after being compressed) might actaully be an advantage.

"Because of its chemical inertness, PTFE cannot be cross-linked like an elastomer. Therefore, it has no "memory" and is subject to creep. This is advantageous when used as a seal, because the material creeps a small amount to conform to the mating surface. However, to keep the seal from creeping too much, fillers are used, which can also improve wear resistance and reduce friction".

Polytetrafluoroethylene - Wikipedia, the free encyclopedia

Hmm, creeps a small amount to conform to the mating surface. Just might be what the doctor ordered.



Hey, did you know:

"The coefficient of friction of plastics is usually measured against polished steel. PTFE's coefficient of friction is 0.05 to 0.10, which is the third-lowest of any known solid material (BAM being the first, with a coefficient of friction of 0.02; diamond-like carbon being second-lowest at 0.05). PTFE's resistance to van der Waals forces means that it is the only known surface to which a gecko cannot stick".

Polytetrafluoroethylene - Wikipedia, the free encyclopedia

I bet you didn't. Take that, Mr. Gecko.

Oh, and what is "BAM"? I had no idea.

"BAM is a ceramic alloy created from an alloy of boron, aluminium and magnesium (AlMgB14) and titanium boride (TiB2). It is one of the hardest known materials, after diamond and cubic boron nitride. It is also the slipperiest solid known, with a coefficient of friction of 0.02; for comparison, Teflon products have coefficients of friction (dynamic) of approximately 0.04. The material was discovered in the course of other investigations by Bruce Cook and Iowa State University professor Alan Russell in 1999 at the U.S. Department of Energy's Ames Laboratory. "Its hardness was discovered by accident. We had a terrible time cutting it, grinding it, or polishing it," said Russell".

http://en.wikipedia.org/wiki/BAM_(material)

Hope this answers your question.

Best regards, John D.

:monkey:

Twice???

 

[rob066]

I never had flippy caps leak. But I did have one come off. I put the cap on and flipped the tab over. It felt liked the cap locked in place. But it didnt. I was running my saw and I got a whole tank of oil running down my leg. What a mess. I now pull on the sides of the cap to make sure it is locked in place. Good thing because it did not lock a few other times. I learned quickly that flippy caps suck.

 

[J.W Younger]

flippys dont suck, you just gotta be smarter than the cap

 

[blsnelling]

So you're saying the caps were installed correctly, and oil leaked past them? I've never seen one leak that was installed correctly. We're talking about an o-ring seal here. I'll admit, it is easy to not install them right. I still like them though.

 

[o8f150]

Or:

Instead of implying that the asker is a cheapskate, and not even attempting to answer his question, like maybe sharing any experience you might personally have about the o-rings going bad, you might have gone with something like this:

I've never been a big fan of the flippy tops (too clever by half as I like to say), I suppose that once one learns to think like a flippy top, there's a remote chance that they can actually be properly closed with reasonable success on something approaching a consistent basis.

Quirks aside, it stands to reason that the o-rings might just start to lose their effectiveness after a while, and might just be good candidates for replacement. It's also possible that a replacement o-ring might actually be of higher quality than the stock ones. Many manufacturers use, and a lot of hardware stores stock, "Buna-N", which isn't particularly good at anything except being inexpensive. Viton is exceptionally good at standing up to petroleum-based products like the oil and gas we run in our saws. Are the stock o-rings viton? Well who knows? And who really cares, since viton o-rings are so readily available from a wide variety of sources, and probably for a whole lot cheaper than you could get stock ones from Stihl for, if they sell the o-ring separately at all.

So the OP got me thinking, and I took the cap off of my 460 and checked out the caps and o-rings. Right off the bat, the o-rings are totally normal, off-the shelf o-rings, and the caps seem to be interchangeable, with the o-rings exactly the same size. Hell, of a start, I say to myself.

Measuring up both the caps and the o-rings, I make them out to be Dash 214, which has a fractional size of 1" ID x 1.25" OD, and an actual size of 0.984" x 1.262". This sorts well with the measurements I took of the cap (about 1.10" diameter where the o-ring sits), and of the o-rings themselves, which were about 1.01" ID and 1.28" OD (after being in service for about 3 years).

They actually seem to be in pretty good shape; still plenty pliable, not torn, and still fairly round; but could they stand to be replaced with something that might be a little closer to stock specs, and maybe a superior material too as an added bonus?

On closer inspection, the average wall thickness of my used o-rings was about .1315". They were a bit flattened - .1350" high, and 1280 thousandths wide (I would have expected them to be flattened the other way), but replacing them with new o-rings would give me a good .070" tighter seal (((1.262" - .984")/2 - .1315) = .070)), so what the hell, I'm going to replace them.

Plenty of places to buy them

As so often happens when looking into something, I learned something new. There's a material called PTFE (polytetrafluoroethylene - oh yeah, Teflon, of course) that might be even better than viton for our purposes.

Teflon vs. viton:

hydrocarbon resistance: Viton good, teflon excellent
water resistance: Viton poor, teflon excellent
tearing: Viton fair, teflon excellent
abrasion: Viton good, teflon excellent
compression set: Viton good, teflon fair

This last one, compression set (how well does it spring back to its original shape after being compressed) might actaully be an advantage.

"Because of its chemical inertness, PTFE cannot be cross-linked like an elastomer. Therefore, it has no "memory" and is subject to creep. This is advantageous when used as a seal, because the material creeps a small amount to conform to the mating surface. However, to keep the seal from creeping too much, fillers are used, which can also improve wear resistance and reduce friction".

Polytetrafluoroethylene - Wikipedia, the free encyclopedia

Hmm, creeps a small amount to conform to the mating surface. Just might be what the doctor ordered.



Hey, did you know:

"The coefficient of friction of plastics is usually measured against polished steel. PTFE's coefficient of friction is 0.05 to 0.10, which is the third-lowest of any known solid material (BAM being the first, with a coefficient of friction of 0.02; diamond-like carbon being second-lowest at 0.05). PTFE's resistance to van der Waals forces means that it is the only known surface to which a gecko cannot stick".

Polytetrafluoroethylene - Wikipedia, the free encyclopedia

I bet you didn't. Take that, Mr. Gecko.

Oh, and what is "BAM"? I had no idea.

"BAM is a ceramic alloy created from an alloy of boron, aluminium and magnesium (AlMgB14) and titanium boride (TiB2). It is one of the hardest known materials, after diamond and cubic boron nitride. It is also the slipperiest solid known, with a coefficient of friction of 0.02; for comparison, Teflon products have coefficients of friction (dynamic) of approximately 0.04. The material was discovered in the course of other investigations by Bruce Cook and Iowa State University professor Alan Russell in 1999 at the U.S. Department of Energy's Ames Laboratory. "Its hardness was discovered by accident. We had a terrible time cutting it, grinding it, or polishing it," said Russell".

http://en.wikipedia.org/wiki/BAM_(material)

Hope this answers your question.

Best regards, John D.

next tiime ct just put the whole book on as a reply,,:hmm3grin2orange::hmm3grin2orange: for me the flippy caps are great i really like them

 

[RAMROD48]

I cant believe the number of people that are DUMBER than a flippy cap...

 

[Jtheo]

Well first off...I don't understand why you thought filling the oil tank up for storage was a good idea?? Just curious!!

Second what makes you think the oil leaked from the flip cap??
(my saws leak--if oil left in tank--but they leak at the bar oil hole)
I either drain mine out (for storage) or just lean the saw over to the side of starter cover...no leak. Lots of folks have this problem.

You shouldn't need to change the O-ring--unless damaged- but I highly doubt that all these saws could have damaged O-ring.

I've only had one flip cap that leaked--(and also the oil cap)--my problem was the two parts that make up the cap--(one black and the other white) one of them had cracked--no way to fix.
I replaced the cap--about $8-- and no more leaky cap--just the bar hole leak.

Hope this helps...

J2F

A Stihl owners manual says for long term storage drain the fuel tank and run the fuel out of the carb.

Then fill the oil tank and store the saw....

 

[Jtheo]

I spoke with a technician at Stihl in Virginia Beach last week, and was told that the flip caps have been improved.

He also said that any older caps that are giving trouble will be replaced at no charge regardless of the age of the saw.

 

[CT_TreeGuy]

"I spoke with a technician at Stihl in Virginia Beach last week, and was told that the flip caps have been improved".

Yes, they heard that some people were actually managing to secure them properly, and have redesigned them to be even more incomprehensible.

I hope this doesn't mean I have to write a new book on the subject.

 

[sloch24]

Wow..

That's a lot of replies about flippy caps!

To answer some questions that were asked, no, I'm not too cheap to buy new caps, but if they only need o-rings, I thought I'd ask if anyone had replaced them.

As someone already stated, the owners manual does state to fill the oil tank prior to storage.

As for the question about how I know the oil is draining from the caps, there is a snail trail from the caps. I know that oil will drip out of the bar oiler hole on the body of the saw. Some saws more than others (I'm not sure why that is either), but this appears to be flippy cap related!

Also, I didn't know that they were going to sit for over a year, I just haven't had a chance to cut any wood. I cleaned them all up, sharpened all of my chains, and filled the bar oil reservoirs so all I had to do was put gas in them and start cutting!

Thanks for the detailed o-ring post. If you end up using a different type, please let us know how it works out!

Brad: yes, they were installed correctly. I've never had this happen when I was using the saws on a regular basis, I guess having them completely full and storing them for over a year was my problem. As someone else pointed out, maybe there was a spec of dirt on the o-rings that caused a problem.

I should also mention that NONE of these saws were bought new by me. I'm a second-hander, and who KNOWS what the previous owner did to the caps. I bought a 440 once that had half of the flippy cap melted off. It looks like the set it on the muffler when they were adding oil.

I haven't investigated exactly WHY they are leaking, it just appears that they are (or did). My 260 emptied the whole tank, the 440 just half.

I too have always liked these caps. This is my first bad experience with them.

Thanks for all the constructive replies!