Stihl 056 Bosch Ignition

[J.Van671]

Hey,

I have a Stihl 056, have done carb kit spark plug and fuel filter, intake boot in good shape no rips/tears(in overall great shape mechanically). Saw fires up and runs for 20-30 seconds then quits, I set the saw down and fire it back up, runs for 15-20 seconds and quits, will do this and never run longer, when it decides to quit, throttle application does nothing. my ground wire to the kill switch has the jacketing flaked off so I am assuming my ignition module is the issue? Any help is appreciated.

 

[Mad Professor]

Bosch ignition? Mine would run a few minutes. If Bosch find the @foggysail fix here

 

[hotshot]

Hey,

I have a Stihl 056, have done carb kit spark plug and fuel filter, intake boot in good shape no rips/tears(in overall great shape mechanically). Saw fires up and runs for 20-30 seconds then quits, I set the saw down and fire it back up, runs for 15-20 seconds and quits, will do this and never run longer, when it decides to quit, throttle application does nothing. my ground wire to the kill switch has the jacketing flaked off so I am assuming my ignition module is the issue? Any help is appreciated.

Easy & cheap to check for that possible ignition issue with an in-spark tester. Canadian Tire or Princess Auto has them.

Keeps you from chasing those ghosts in the fuel system/carburetor.

Pull the starter cover & post a pic of the flywheel, then we’ll know which ignition you have.

 

[J.Van671]

Easy & cheap to check for that possible ignition issue with an in-spark tester. Canadian Tire or Princess Auto has them.

Keeps you from chasing those ghosts in the fuel system/carburetor.

Pull the starter cover & post a pic of the flywheel, then we’ll know which ignition you have.

I did some digging and it is definitely a Bosch, Stihl dealer confirms. I do have multiple inline testers and it did show spark before just wasn't sure if it would all of a sudden lose it for whatever reason. Unfortunately i put it all back together without taking photos of the flywheel and ignition module but now that it is together it does fire up no problem, L screw is at 1 turn and H screw is at 1 1/4 turn as per the book. It fires up and runs but almost sounds like the carb runs out of fuel, once it quits i can set it down for a second and it fires back up and runs for 10-12 seconds and quits again.....back to where i started.

 

[cookies]

run it with a in line spark tester on it...when it shuts off check it quickly for spark. Quit guessing

 

[J.Van671]

run it with a in line spark tester on it...when it shuts off check it quickly for spark. Quit guessing

i had done that before and it maintained while it quit, I'm wondering if it might be a fuel issue, as it has sat for a while so whether the intake boot is cracked where the fuel port from the fuel tank is or possibly my need lever is set to high. has a new fuel filter and new fuel, tank has been rinsed a few times with fresh fuel.

 

[Mad Professor]

I did some digging and it is definitely a Bosch, Stihl dealer confirms. I do have multiple inline testers and it did show spark before just wasn't sure if it would all of a sudden lose it for whatever reason. Unfortunately i put it all back together without taking photos of the flywheel and ignition module but now that it is together it does fire up no problem, L screw is at 1 turn and H screw is at 1 1/4 turn as per the book. It fires up and runs but almost sounds like the carb runs out of fuel, once it quits i can set it down for a second and it fires back up and runs for 10-12 seconds and quits again.....back to where i started.

I have an 056M w Bosch that would run for a couple minutes, even cut. Then a dead dog unless you waited ~ an hour.

 

[cookies]

do it again, if it has spark then check your carb gaskets for being in the correct placement. A vacuum leak will elevate rpm, give it a spritz of mix on the air filter when it dies, check the fuel cap vent. I would leave the inline spark tester on the saw during all of this

 

[J.Van671]

so I checked and double checked then checked again to be sure, gaskets are all seated correctly, I've had the carburetor off several times today alone, I had to reset my needle lever in the carburetor as I believe it was set to high under the diaphragm leaving it open slightly causing the saw to load up with fuel and die.

got it to idle for about 5-10 minutes with no issues, it ended up quitting on it's own, when I restarted the saw it smoked pretty good indicating it was loaded with fuel. tried leaning out the idle mixture screw to see if that would help. I've double checked the intake gasket and the pulse lines for cracks and or other issues but have seen no indications of failure. all of this is done with the inline checker on it and I don't seem to lose spark, I have yet to try spritzing fuel into the carb when it dies, i'm really leaning towards it being a too much fuel causing it to load up and quit.


also a correction, the Saw is an 056 AV electronic Quickstop and not just an 056 as I originally stated.


thanks for all the input and help

 

[cookies]

kinda wondering if the limiting circuit in the carb is leaking, I'd check it

 

[J.Van671]

Everything appears ok in the carb, i unfortunately did not remove the welch plug as i do not have a replacement for it. The carb had soaked in combustion chamber cleaner for 2 days to remove all debris and to be 100% honest in regards to a limiting circuit i don't know what i'd be looking for? Also having difficulty finding a diagram.

 

[cookies]

My mistake, these do not have the limiting circuit in the carb, I would suspect the valve nozzel is leaking. what carb/model is it? find the beg for manuals thread and request the ipl/repair manuals

 

[J.Van671]

It's a Tillotson is about all i have, local Stihl dealer ordered the gaskets for me, can't get a carb kit for it through the dealer.

 

[hotshot]

Photos help….Near impossible to troubleshoot over the ‘net. Is your carb the common Tillotson HS-118? Kits are cheap & all over fleabay RK-23HS

If the metering lever is forked on the end, then the metering diaphragm must have a slotted button, not the flat type. You can’t mix those parts. Also, there’s no intake gasket used on those saws.

https://tillotson.ie/wp-content/uploads/2015/07/techinfo_hs_us.pdf

 

[J.Van671]

Hopefully the photos attach, looks like it is an HS118, the short video is after is ran, carb is flooded with fuel.


My needle lever is forked as you can see but neither the new diaphragm nor the one i removed have slots for it to fit in to.

 

[hotshot]

It’s slotted. Make sure the diaphragm button is slid sideways into the slotted metering lever end, not setting on top of it.

That would flood it out for sure.

Also make sure the fuel pump diaphragm is against the carb body, then the gasket & cover. It’s just opposite of the order from the metering side.

 

[cookies]

that diaphragm button looks like it has the slot in the button to slide it into the fork on the lever. When you took it apart you likely bent the lever.

 

[J.Van671]

I likely had bent the lever yes, as per different web searches says to set it level as i have done or believe to the best of my knowledge is correct. Unfortunately the diaphragm i have and the one i removed don't appear to have slots to accept the lever in to.....

 

[hotshot]

Your fourth pic shows the correct one, guessing you need to order a kit & start over.

 

[cookies]

https://chainsawr.com/products/stihl-chainsaw-carburetor-diaphragm-new-1110-121-4700-st-207