Stihl Grub Screw Tank Vents?

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I've read a lot of stuff from everybody..what I like to read the most contains information about chainsaws, not into personal stuff. We all disagree once in a while about things like what's the best saw or what's the best oil but that's only normal. I'm sure you and Brad are both nice people. I've read good things from you and him both.
 
That doesn't sound very conclusive, sounds like a guess.

Let's see one that one of you guys slotted!!

In this case, I doubt it, there is likely more to Brad's failure. He just likes to find something to blame
when something goes "boom".

Kinda like the bent Ms170/180 rod?
Answer you came up with: Stihl made them too cheap!
It is Stihl's fault!!

Cause nobody ever tried to "Snellerize" one!!!

Because I am not "worshipful"? Anyone that dares to disagree with or challenge you?

You must have not read many of Brad's tantrum posts......
50,000 posts is a lot of crap to read.

Just take a look at these posts you made in this thread alone. They have nothing to do with the topic at hand. These posts are nothing more than an effort to cause trouble. That is the very definition of a troll.
 
I've had differences of opinion with several posts on AS but usually I don't try to make it personal, in fact I usually just read it and don't reply to it. I'm kinda like most people, trying to learn every day, I sure don't pretend to know everything about a saw, I get lots of saws in here to work on and get stumped lots of times. Also, I don't pretend to know anything about porting or port timing, etc. I just clean the ports out and once in a while do a muffler mod but that's about it.
 
I'm quite sure he's already there. He has the same exact nasty attitude as a few of the others.
Upon further consideration, I suspect that HarleyT is actually a member that has been previously banned and signed up with a new userid. He is referencing things that he would know nothing about if his history only went back to 2014. Either that, or another AS hater is feeding him lines and he's just a little puppet.
 
I mill with my 066, it don't have a grub screw vent, but when it starts to starve for fuel, on a low/empty tank I shut it right down. So far running down to empty has done my saws NO HARM. I see no difference between this and a clogged vent. No fuel no run.

I have have had saws with clogged vents, and they run like crap so bad they won't cut, and/or die.

There is nothing wrong with grub screw vents and for $2 worth of fuel line you can fix them forever. All my 056s 038s and 028s say so.

BTW, the 056 has the vent, w/grub screw in the filler cap
 
I see no difference between this and a clogged vent. No fuel no run.
They are clearly two different physical effects with different characteristics. In one case the pressure differential across the jet is progressively reduced, but there is still fuel available. Eventually the mixture will become so lean it doesn't run, but it will do that by moving gradually leaner from where it started.

It the other there is no reduction in pressure across the jet, but the fuel becomes intermittently unavailable. This happens more quickly and it is more obvious.
 
I still learned a lot from the arguments and disagreements.

Might I suggest to quit typing and using the term AS members. When I first seen that term used in a heated argument sentence in this thread I suspected it was a typo or new type of text term only using one S instead of two. (take time and type out the letters. Others might think we are politicians using bad misspelled words:hi::yes::innocent:.
 
They are clearly two different physical effects with different characteristics. In one case the pressure differential across the jet is progressively reduced, but there is still fuel available. Eventually the mixture will become so lean it doesn't run, but it will do that by moving gradually leaner from where it started.

It the other there is no reduction in pressure across the jet, but the fuel becomes intermittently unavailable. This happens more quickly and it is more obvious.

Conjecture.

This would depend on the extent of the clog.

Besides that it takes a good amount of negelectful cleaning, time and crud to clog a grub screw vent line. The OEM lines I have seen have deteriorated before they clog, then they piss out fuel when you tilt the saw the wrong way.

Another thought is was it a OEM line with the OEM grub screw? If not, or some sort of mix and match, may be the problem. That is the screws threads worked it's way into the line
 
Conjecture.

This would depend on the extent of the clog.
Even a total blockage will not change the mixture instantaneously. The rate of fuel leaving the tank is not that large and will take time to reduce the pressure in the tank. It's not the same as running put of fuel.
 
Even a total blockage will not change the mixture instantaneously. The rate of fuel leaving the tank is not that large and will take time to reduce the pressure in the tank. It's not the same as running put of fuel.

Still conjecture/theory.

Get a POS saw you don't care about, Put a needle valve on a tank vent and close it down in stages. See if you get damage or it runs funny and dies before that.
 
Awhile back I had a rotten detoriated vent hose on a chainsaw that has grub screw in each end of the small hose.
I got the Redneck bright idea to change the hose to the tygon type so as the hose would last longer. I pushed both grub screws into the tygon hose (did not screw them in) and checked to see if the hose would allow vacuum using the mityvac and the tygon was soft enough that no vacuum was permitted.:surprised3:(surprised) If it had vacuumed I suspect the soft tygon might have eventually sealed around the grub screw threads and prevented venting properly.

Went back with the harder type tubing and all ok when testing with the mityvac.
 
Still conjecture/theory.

Get a POS saw you don't care about, Put a needle valve on a tank vent and close it down in stages. See if you get damage or it runs funny and dies before that.
It's your conjecture that it will behave like it's running out of fuel before going lean even though it is obvious from how the thing works that cannot be true. How about you put in the time to do the test?
 
Have you guys never run a saw with a vent that wouldn't flow enough? A ported 346 is a perfect example. They often require a vent mod. It's nothing like running out of fuel. It would be very easy to burn one up if not checking for it.

I'm not telling you that your saw WILL burn up or that you MUST change it. I'm simply sharing my personal experience in hopes that it will prevent someone else an unfortunate and preventable loss.
 
If you ever need one, PM me.

They're under a buck here, like deer nuts LOL.
If you ever need one, PM me.

They're under a buck here, like deer nuts LOL.[/QUOTE

(the little red rubber check valve on page 2 in the picture)
It's used as a check valve behind the accelerator pump diaphragm on a Ford Motorcraft 2150 2 barrel carb and you can buy them (order them) at most any automotive store like NAPA for example.
 

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