Common service tool manual

[kneedeepinsaws]

Looking for a manual that shows the error codes and what they mean. Would also like to have explained what the fuel setting number actually means.
Any help is much appreciated

 

[ray benson]

I don't have any error code manuals for Husqvarna or Stihl. Not sure what fuel setting numbers you are looking at? Need specifics.

 

[DND 9000]

If you mean AutoTune, it is normaly like that:

The lower the shown setting is, the richer the unit is running.

The higher the shown setting is, the leaner the unit is running.

Such information does always not show the fault itself, but it can indicate some faults, were the properly trained technician knows where to look. This does never replace the traditional diagnostic methods. It is additional info.

 

[kneedeepinsaws]

If you mean AutoTune, it is normaly like that:

The lower the shown setting is, the richer the unit is running.

The higher the shown setting is, the leaner the unit is running.

Such information does always not show the fault itself, but it can indicate some faults, were the properly trained technician knows where to look. This does never replace the traditional diagnostic methods. It is additional info.

I do mean auto tune.
I have a hard time wrapping my head around the fuel setting for high and low in which a higher number is lean…
Do you know what the number means? This would help me understand and rid me of the thought process that higher is richer

 

[ray benson]

Out of an autotune manual
When the product is used, AutoTune / Carb Control automatically sets the carburetor optimally in spite of variations in conditions, for instance, type of fuel. The fictional values below indicate a comparison between different types of fuel.
• Commercial petrol, 95 octane, high energy fuel 70-90
• Alkylate fuel e.g. Aspen 60-80
• E25, commercial petrol with 25% ethanol 40-60
The values are fictional and indicate a comparison between the different fuels. The range is due to other variations of the product deciding where your product has its optimum setting for a specific fuel. The higher the number, the higher energy content in the fuel and thus lower fuel consumption.

 

[kneedeepinsaws]

Does anyone know the leanest numbers auto tune can reach before it’s maxed out?

 

[DND 9000]

150 is the end.

 

[kneedeepinsaws]

150 is the end.

Thank you!
You’ve been really helpful I’d like to ask you another question.
What are , say, on average your fuel numbers for low and high for the saws that you see that are running properly?
I am pretty sure that elevation, temp and oil ratio will have an impact. I’m trying to ascertain by how much roughly.

here we are running saws at 3500 ft @40:1 with trufuel and I’m finding the ones that I have plugged in are at 100-110 for the high.
I’m trying to establish some baselines here is all, thank you!

 

[DND 9000]

I am pretty sure that elevation, temp and oil ratio will have an impact.

Yes this has an effect. Your number 100-110 can be right according to the height you use the saw. The higher you go the leaner tuned has to be the carburetor, because of less oxygen in the air and less air pressure.

Normally the range is somewhere between 70 and 110 in most cases.

It also depends on the fuel you use. You use trufuel, which is some kind of alcylate fuel if I know right. Compared to pump fuel, engines that run on alcylate fuel have to be tuned slightly richer. This has to do with the density of the fuel.

 

[kneedeepinsaws]

Yes this has an effect. Your number 100-110 can be right according to the height you use the saw. The higher you go the leaner tuned has to be the carburetor, because of less oxygen in the air and less air pressure.

Normally the range is somewhere between 70 and 110 in most cases.

It also depends on the fuel you use. You use trufuel, which is some kind of alcylate fuel if I know right. Compared to pump fuel, engines that run on alcylate fuel have to be tuned slightly richer. This has to do with the density of the fuel.

Thanks! You are a source of good info! Yes truefuel is an alkalayte type of fuel.
Would you say depending on the conditions running 50:1 instead of 40:1 would have auto tune adjust easier?
I’m gonna conduct my own experiments. The control will be the elevation and temp, oil and fuel and the variable will be 50:1 vrs 40:1.
I don’t know exactly what I’m looking for yet but it would be interesting to see the data. Going to do a default reset of the fuel settings before each test. They will have 2 mins of idle warmup time and then hit the same wood with the same bar and chain for 30 minutes. Afterwards plug it in and look at the averages between the two. what do you think?

 

[DND 9000]

Sounds intresting these kind of test. There should be a slight difference running 40:1 and 50:1. As I think of it, it should be like the following. On the 40:1 mix you have more oil in it as on 50:1. With the 40:1 mix the engine should run a little bit leaner, but AutoTune will adjust for this with the ignition timing and fuel flow. (should give a little bit more fuel) That means the mixture should be richened a little bit. If you go from 50:1 to 40:1 you replace (when it goes through the jets) fuel with oil. That`s why the mixture gets leaner and it is more (a little bit) thicker to flow through the jets.

In the past I made a test with a adjustable carb saw (MS 361) were I went from 50:1 to 25:1. It was a real noticable difference. It was around 1300-1500rpm differnce on the high speed. With the 25:1 mix without retune the saw reved significantly faster and was running leaner and I had to retune it for the new mix.

 

[kneedeepinsaws]

Sounds intresting these kind of test. There should be a slight difference running 40:1 and 50:1. As I think of it, it should be like the following. On the 40:1 mix you have more oil in it as on 50:1. With the 40:1 mix the engine should run a little bit leaner, but AutoTune will adjust for this with the ignition timing and fuel flow. (should give a little bit more fuel) That means the mixture should be richened a little bit. If you go from 50:1 to 40:1 you replace (when it goes through the jets) fuel with oil. That`s why the mixture gets leaner and it is more (a little bit) thicker to flow through the jets.

In the past I made a test with a adjustable carb saw (MS 361) were I went from 50:1 to 25:1. It was a real noticable difference. It was around 1300-1500rpm differnce on the high speed. With the 25:1 mix without retune the saw reved significantly faster and was running leaner and I had to retune it for the new mix.

I have been thinking that for a while now, in fact I am 95% sure what your saying will happen if applied.
My goal is to see if there is a performance difference between the two, throttle response in particular. Is it harder for auto tune to lean out the mixture or easier? Or no difference?
Does auto tune learn quicker with a slightly leaner mix than a richer one? Or no difference?

I def have a bog off of idle with this saw, but there is only 4 hours run time. Which brings up another point.
The manual for common service tool states that you should never do the factory reset unless there is a major hardware change. To me this sort of says that auto tune does indeed make a broad fuel map over time with your particular running conditions. By doing the factory reset you might be throwing away all of that learning time. Maybe this is the “break in” mode that people say they can fee after so many hours. In reality it’s not an actual break in mode but it is developing a fuel map that in the end only makes small adjustments instead of big like in the beginning.
Of course this could all be confirmed by an actual husky engineer lol but they don’t have time for us common folk I’m sure
In the end we run a battery of tests and try and keep the controls controlled and see what happens in the end…