Husqvarna 125b issues

[Rivets]

Which means your way is the only right way?

 

[StarTech]

Which means your way is the only right way?

No just means that I only take less than 15 minutes to tune a chainsaw or other 2 cycle vs an hour of hunting the sweet spot. An Echo chainsaw can be a bear to tune if you don't use their procedure of tuning idle first.

 

[bertsmobile1]

FWIW I always do mine high first then low.
This method works best for me particularly as I have very limited technical information available so am often working blind as the owners have usually had a fiddle using wrong information they pulled off you tube for the right brand but wrong model .
I rather feel it is one of those technique prefference things like setting valve lash at TDC or as the opposing valve just opens .
If nothing else , a small adjustment on the H makes a big difference to the engine while big adjustments on the idle make small differences anywhere except at idle .
I have noticed some machine manuals say to do then H then L while others say L then H for what appear to identical carbs .
Machine manuals seem to fixate on over reving damaging the engine so perhaps there has been a rewrite to avoid the brain dead running engine way above the speed limits of the bearings & doint severe internal damage although I am yet to see any internal damage other than pistons that break up that could be attributed to over reving the engine.

 

[bertsmobile1]

No just means that I only take less than 15 minutes to tune a chainsaw or other 2 cycle vs an hour of hunting the sweet spot. An Echo chainsaw can be a bear to tune if you don't use their procedure of tuning idle first.

I will pay you this one though.
The modern low emission carbs with the very long shallow needles are a PIA to find sweet spots as some have a running range of two full turns .
Fine if you have a meter up the exhaust pipe but a PIA when working by ear .

 

[StarTech]

Ears are shot here so it is tach that I use now. Besides it can be like the CS-370 I did Monday.

 

[Rivets]

Star, you state manuals are full of mistakes and for reference only, but when ever you try to prove a point you use illustrations which you cut and paste from a manual. So you’re telling us that every manual which states H before L is a mistake, but L before H, plus your illustrations are correct? Can’t have it both ways. Second, Tecumseh might be dead, Briggs on life support, but the theory as to how the five different circuits in a carb work has not changed. It doesn’t take me anywhere close to an hour to adjust 99% of the carbs I work on, both 2 & 4 cycle. Using my ear and a Vibratach I can normally can do a carb in about 20 minutes. In your mind I might be an old fart who shouldn’t be allowed around an engine, but the procedure I taught and posted has served me well for the last 50 years and just because you do it a different ways, doesn’t make yours the absolute truth. Just means there is more than one way to get an old fart fired up.

 

[StarTech]

First Rivets don't be assuming things. It make an (ass)(u)(me).

Yes I said manuals do have printed mistakes like in the case of the Tecumseh L-head manual a half truth as it assume both carburetor styles are tuned the same. If you note the last image is a Wabro make and model specific tuning. Each make and model carburetor will have different tuning procedures depending on what it is on. Some manual errors are translation errors too.

It like the Kawasaki 57001-1003 oil pressure gauge adapter that the service manual only give partial info. Actually doesn't indicate if 1/8-27 NTP or 1/8-28 BSP threads. Big difference when buying after market parts.


In my case I need 1/8-28 BSP threads for the pressure switch so I be either rethreading the switches or the engine's port. I just can't spend $30 for one switch plus another $20 for shipping for $4.30 ($7 with shc) per switch. Just ordered 5 switches for $34.87 including 2 day shipping.

It is also like the JD Z915 where the 2015 service manual stated to remove the axle hub with a hub puller for axle seal replacement. And when they reprinted the manual in 2020 they changed it to remove the axle for seal replacement. The little change costed me $200 for a tool that I could not use.

 

[bertsmobile1]

Full of mistakes is a bit of an over statement.
Having written, proof read & updated them on a contract basis for decades I can assure you that most are as close to 100% correct at time of printing as any publication can be.
However what happens is things change from the time the manual is published to the time you end up reading it 3, 5 , 10, 20 ,50 years later .
What differs is how the particular company handles any things that changes &/or post publication mistakes that are found.
Now days when they are digital they can be updated very cheaply to cover materials &/or specification changed but in the paper only days , updating was a major cost so in most cases manufacturers simply issued dealer notes and in many cases these never made it into the manual as the dealers were expected to keep them with the manuals and notify their technicians about the changes .
Manuals were never meant to be used by ameteurs apart from a very small number of companies like JD who write their manuals for the mechanically ignorant public .

Then companies change the method of doing things and this I fear is what you two are locking horns about .
Public Liability assesors look at things and decide that there is a possibility of a run away engine self destructing if a lazy tech does some thing like hold the throttle WFO with a velcro strap / tie down start an engine off propane or starting fluid then allow it to scream WFO in the shop without the cooling covers on and no load on the motor.
For all we know this could have happened.
Then smart arse lawyers sue the manufacturer because the manual does not say not to tie the throttle open so the proceedure gets changed to an idiot proof one .

There is no real difference in either technique.
Both the H & L need to be adjusted and both affect each other so adjusting the one will require a compensating adjustment to the other .

If you have access to initial settings then you can adjust Low speed first because the engine will start and run at low speed .
However if you don't then it is easier to set WFO then work back because as you are letting the throttle off you should be able to hear that it is starting to run rich or lean or not responding as it should .
I am in the latter category and while I do write down the needle settings before I strip a cube carb, often these are very much wrong because either the owner has had a fiddle or has been adjusting to compensate for failing diaphragms or air leaks.
Thus when properly cleaned & rebuilt the owners settings are so far out the machine will just not start .

It is the same story as valve adjustment
TDC or Base Circle , makes little difference unless it is a very old cam grind with a long slow closing ramp ( makes the valves quieter ) .

So you two are argueing abut nothing.

Rivets is working off what was the original information and Star is argueing off the updated information , both work, neither is more correct than the other

 

[Mower King]

I'm going to show my age with this old quote to Rivets and Star but...."there is more than one way to skin a cat"

I do know those "cube" carbs on hand-held equipment are very sensitive to adjustment and can be adjusted out of spec real easy, so that they won't even start. Most the pros can probably get them running right but, your guy wanting info on how to adjust them, probably not so easy!
We don't work on chainsaws anymore but, I still get to "enjoy" trimmers and blowers.

 

[StarTech]

Now I understand why the EPA doesn't want techs to have the carburetor adjustment tools. And I don't blame them either though it makes my job a lot harder as I at times have to make the tools.

Now do I loan those custom tools out or give out the design plans? H*** no.