How long can you keep the throttle wide open without load?

[Gratewhitehuntr]

Iridium plugs consistently go 70K miles, and if you re-gap them there is another 30K in there.
The air filter is 10x more important than the oil filter.
The new nat-gas oil, such as Pennzoil ultra platinum 0-40 is BY FAR the best BASE oil available in my lifetime.

Iridium lifespan aside, let's consider the potential for damage when changing spark plugs.
I know zero people (other than myself) who are serious about blowing and washing trash out of recessed plug holes before removal.

 

[lone wolf]

In regards to reving the saw with no load. I'd bet money I could run a saw wide open no load for an entire tank of gas with no issue. There is no load on the motor and as a result it's running rich and cool.
Why do guys think this would hurt anything?

Depends on if the saw is tuned to the stock RPM factory setting, if it is lean you are looking at an overspeeding condition which could do piston damage.

 

[Gratewhitehuntr]

if it is lean you are looking at an overspeeding condition which could do piston damage.

In which alternate reality is lean piston damage caused by piston speed?

edit to point out: it should be clear by now that some of us live in a reality separate from the one inhabited by NPCs
Therefore, this is a serious question. Which alternate reality? The one where oil-is-oil-is-oil?

 

[ZeroJunk]

Yes we know you "techs" send saws and most o p e out bludging fat to cover ya ***. Nobody is saying you are in the wrong so chill willy don't take it as a personal attack we all know you are dealing with braindead clueless consumers... Anyone with half a brain isn't taking their chainsaw to a tech for a "service and tune up"

I'm not a tech, never been to a Stihl class. I just repair them, for the techs.
Never had a saw come in for a tune up, whatever that is..
But, I will never send a repaired saw out lean, that is a fact.

Fortunately, saws are pretty forgiving as far as tuning goes.
Which is why every swinging **** on the internet thinks he is the best saw tuner who ever lived.

 

[Sidecarflip]

I agree with that 110% Just got done repairing an H linkage for a Case Extenda Hoe and the owner wasn't paying attention to it when digging out a concrete pad and actually twisted it and broke on ear off it. I rewelded the broken ear back on and straightened it best I could and told him it was on borrowed time and I really need to make up a new one which he declined of course. The part is NLA. What really contributed to it's demise, besides his inattention was the fact that he NEVER greased it. Amazing. He will be back and I'll be fabbing a new one and relieving his wallet accordingly. Just had a Terex front loader bucket dropped off where the owner actually ripped off one of the grouser teeth as well as the tooth mount. That will be a job to repair. and it won't be cheap either.

I get that stuff all the time here. It's amazing how people abuse equipment. Not just never changing the oil either.

 

[Gratewhitehuntr]

Which is why every swinging **** on the internet thinks he is the best saw tuner who ever lived.

There are a couple ways to look at this.
I'll use IronHorse as an example, with some caveats because I dunno how spicy his name is.
Youtube didn't exist when I started fixing saws.
I "started fixing saws" before I started running saws, when my Dad said I could run one he'd blow't up
If'n I could fix it!

I've watched quite a few Ironhorse videos, he has good ideas and bad, but I definitely learned SOMETHING.
He's had the advantage of time, and watching the tech evolve.
Some of the younger saw guys on YT, I would only watch as a proxy for Bennie Hill.
DynoJoe gets special mention, this man is doing the Lord's Work. Watch his vid on DIY pipes.

You might get some lulz when I crack on about wrecking Chyneesium cylinders, because "they aren't REAL saws!"
OK, they're junk. Fair enough. I've bought and sold a *****-pile of saws, totally agree that quality matters.
What it would be, if I learned to port on grandpappy's pile-o-SP125s? A travesty.
Cry yourself to sleep imagining if a minty Mac Sp125 was the first cylinder you ever ruin't with a burr.

Trash-picked saws, and experimenting on this junk for personal use (or work saws) is very liberating.
Think about grinding finger ports with a dremel.
Now, plunge bore that on the vertical mill. Boom. One cut, with a mic on depth.
Heck you can even radius the end of the port with endmill profile selection. PERFECT radius.
Where there's a mill, there's a way!

What does it hurt me to test out how-lean a saw can be run? A $30 p&c? Another trash find?
EDIT for correct answer: a few pulls before the backup saw pops off!
Now I'm tempted to buy a tach, so we can have a "WT over-revving challenge!" just to see the

Totally unlike the experience of a shop mechanic.

 

[ZeroJunk]

I'm curious as to how you guys think the manufacturers tune them.
I can tell you for a fact that the OEM carburetors come with the limiters adjustable. The little red palstic thingamajigs are stuck out where you can easily remove them and push them in to the locked position when or if you want. The all metal ones that adjust with the small octagon are out and have to be pushed in to lock, when and if you want to.
So, you think they got a stick of wood out there somewhere, and some dude with hearing aids ?

Or, do you think they use a tachometer.

 

[HansFranz]

Iridium plugs consistently go 70K miles, and if you re-gap them there is another 30K in there.

I have 165k miles and over 20 years on the OEM plugs in my F-150.

Even though it runs fine, I might have changed them by now if it weren't for the fact that pulling out the plugs on my engine reportedly often rips the aluminum threads out of the heads...so my SOP is "If it ain't fixed, don't break it!"

 

[bwalker]

Depends on if the saw is tuned to the stock RPM factory setting, if it is lean you are looking at an overspeeding condition which could do piston damage.

Even if a bit lean with no load on the motor it would run a long time. That and the factory no load rpm is usually very conservative.
With these saws failure to overspend isn't going to happen as the have short strokes and as a result their pistons speeds are low.

 

[bwalker]

There are a couple ways to look at this.
I'll use IronHorse as an example, with some caveats because I dunno how spicy his name is.
Youtube didn't exist when I started fixing saws.
I "started fixing saws" before I started running saws, when my Dad said I could run one he'd blow't up
If'n I could fix it!

I've watched quite a few Ironhorse videos, he has good ideas and bad, but I definitely learned SOMETHING.
He's had the advantage of time, and watching the tech evolve.
I also have this advantage, over gen Z and those to come. I won't care if they don't listen.
Some of the younger saw guys on YT, I would only watch as a proxy for Bennie Hill.
DynoJoe gets special mention, this man is doing the Lord's Work. Watch his vid on DIY pipes.

You might get some lulz when I crack on about wrecking Chyneesium cylinders, because "they aren't REAL saws!"
OK, they're junk. Fair enough. I've bought and sold a *****-pile of saws, totally agree that quality matters.
What it would be, if I learned to port on grandpappy's pile-o-SP125s? A travesty.
Cry yourself to sleep imagining if a minty Mac Sp125 was the first cylinder you ever ruin't with a burr.

Trash-picked saws, and experimenting on this junk for personal use (or work saws) is very liberating.
Think about grinding finger ports with a dremel. Now, plunge bore that with the vertical mill.
Heck you can even radius the end of the port with endmill profile selection. PERFECT radius.
Where there's a mill, there's a way!

What does it hurt me to test out how-lean a saw can be run? A $30 p&c? Another trash find?
EDIT for correct answer: a few pulls before the backup saw pops off!
Now I'm tempted to buy a tach, so we can have a "WT over-revving challenge!" just to see the

Totally unlike the experience of a shop mechanic.

Iron horse is a complete tard who doesn't even have a basic understanding of how a two cycle motor works. Worst hack on YT.

 

[bwalker]

I'm curious as to how you guys think the manufacturers tune them.
I can tell you for a fact that the OEM carburetors come with the limiters adjustable. The little red palstic thingamajigs are stuck out where you can easily remove them and push them in to the locked position when or if you want. The all metal ones that adjust with the small octagon are out and have to be pushed in to lock, when and if you want to.
So, you think they got a stick of wood out there somewhere, and some dude with hearing aids ?

Or, do you think they use a tachometer.

Of course they use a tach!

 

[bwalker]

I have 165k miles and over 20 years on the OEM plugs in my F-150.

Even though it runs fine, I might have changed them by now if it weren't for the fact that pulling out the plugs on my engine reportedly often rips the aluminum threads out of the heads...so my SOP is "If it ain't fixed, don't break it!"

That is a huge issue qith certain Fords.
I've found that if you don't change plugs out long term you end up with coil failures.
I use NGK double Iridiums in all my vehicles and change them at 100k. I also use antiseize on the threads...a point that will certainly get someone riled up.

 

[bwalker]

Not so much that. But, most of the aftermarket clips have a metal tab on one or both sides and the metal fatigue will break them off. Regularly. Old 041's and that vintage came with them. But, the RPM's were quite a bit slower. Stihl took the tabs off, probably for that reason.
In the event I use an aftermarket piston with tabs I take a pair of side cutters and cut them off.

That's why I don't use AM parts.
And that's smart to cut the ears/tabs off. That circlip design has been known to be problematic since forever.
I also make sure I orientate the circlip in the up and down position.

 

[bwalker]

If you have your own little pet saws and you want to try to keep them tuned perfectly that is fine. But, many of us repair saws. The RPM increases quite a bit as the saw comes up to operating temperature on top of changes between your fuel and who ever plus temperature and altitude.

I would have to be a bigger moron than I am to send a saw out cold tuned to the max.

They do need to be up to operating temp to tune.

 

[Breckinridge Elkins]

You aren't supposed to gap Iridium plugs. If you've gone through the trouble to remove them, why wouldn't you just replace them?
Those Ford's will spit out the factory plugs too. Leaving them in that long is magical thinking. It just makes it more likely some aluminum will follow them out when you finally have to replace them. I always use antiseize on plug threads. Never had a problem.

 

[Gratewhitehuntr]

I have 165k miles and over 20 years on the OEM plugs in my F-150.

A friend of mine was recently shopping the early 2000s "Triton" 4.6 F150s, I went to check on the thread situation.
My impression is that the 2 valve engines had a couple extra threads.
V10 and some 3 valves had issues, but I couldn't determine WHICH ones. Anyway, that 3v timing setup, derp!

Magical thinking. True. Waiting does make it worse. True.
The big gap does causes coil failures. (this particular COP seems fragile to begin with)
Blow it out, hose PB blaster, blow it out again, lube again. Wait a day, or a week. Hand tools only.
Switch to nat-gas oil to clean out the VVT slip-fit parts, I've seen a couple with stumble at idle for this reason.
And since the natgas oil is usually at the thin end of it's weight range, going to 0-30 would be fine at 165k.

My iridium #s were conservative because forced induction being haut again. It's harder on plugs, ime.
Otherwise, iridium is basically a lifetime purchase in NA engines. Saws are the only copper plugs I still use.

What? Why gap? If people can declare that they won't rev free engines, or change the plugs, I feel zero qualms re-gapping a $15 spark plug.
What not to do? Assume that shelf-gap is consistent, or even the right gap for your engine. haha parts changers FTW!

Iron horse is a complete tard who doesn't even have a basic understanding of how a two cycle motor works. Worst hack on YT.

Dude is definitely peak Boomer. I can learn from ANY man, if only, how NOT to do it.
To say that differently... hmm... wait I'll come up with something...

EDIT: OMG now anti-seize is controversial? um... huh.

 

[HansFranz]

Those Ford's will spit out the factory plugs too. Leaving them in that long is magical thinking.

Naw, "magical thinking" is tearing into a perfectly functional engine when you stand a good chance of breaking it -- to the point of having to pull one or both heads, or dikk around with timeserts or helicoils (and don't get me started on the plastic intake manifolds on a lot of Fords) -- all because you wanted to avoid having to pull one or both heads or dikk around with timeserts or helicoils. A coil pack or two is cheap and easy by comparison.

I talked to a very good local mechanic about replacing the spark plugs and he said, "We generally allow a day or more for it on that engine. Sometimes we get lucky, but don't count on it!"

No thanks. I changed one plug and coil pack when the CEL went on. I'll replace the others if and when I have to -- but not before.

 

[Gratewhitehuntr]

crevice corrosion of dis-similar metals, there is no magic
The problem was the loss of total thread strength when switching from iron to aluminum, then again with a marginal design in aluminum heads, and mechanics doing things by feel. I admit to this, torquing spark plugs by feel (crush washer yield) , and lots of other bolts too.
Not THOSE plugs, and the fact that people are aware of the issue has reduced (as far as I can tell) the "the gun JUST went off!" type snafu.
Note the over-correction. Don't let your BIL win like this

I suspect that the early "spitting plugs out" was the result of crush washers with higher crush torque rating than the maximum torque the mechanic was willing to apply. IIRC once upon a time I was putting plugs in a 4.6 and they had a crush washer which was not sufficiently compressed at the peak (whatever spec we had) torque. It felt strange on the torque wrench.
(that's the sort of thing they quietly change, and forget ever happened)

I have seen 4.6 plugs online with head threads on the plug, claiming it was just spit out including shearing the threads. I cannot know.
Hmm. Now that I typed this out, IIRC the last 4.6 plug set I did was lacking crush washers. Koinkydink?

Just to be clear, at 165K I'm in agreement with Mr. @Breckinridge Elkins , replacement. Real high mileage and age is not the same as a plug abused by forced induction, incorrect fuel mixture, or dropping on the ground Why else? LOL. Plugs are almost free compared to fuel, or my time spent chasing a miss.

 

[ZeroJunk]

In the meantime, I am thinking just how ******* dumb are you people.

 

[Lightning Performance]

Which is why every swinging **** on the internet thinks he is the best saw tuner who ever lived.

You rang?