What's on your bench today?

[Max 201]

Had the same part snapped on my 201. Never noticed anything until I rebuilt it and put a new sprocket cover on. The cover actually came with the insert so I assumed it was common for them to break.

I've already started a list of bits needed because they're either missing or not in good shape on both saws. 

[openspaceman]

On 06/02/2022 at 23:00, bmp01 said:

Might be me but didn't the saw rev up, then start misfiring and drop revs ???

Agree with Spud that sounded rich at idle and the initial rev up didn't sound clear or particularly high revving. Was that from cold, any different warm?

I wouldn't rule out spark plug / ignition trouble for the misfiring from high speed. Broken plug I had on a MS211 made saw impossible to start though, plug was arcing internally through the ceramic.

 

Again as Spud says if blocking the strato port allows it to rev cleanly then its not ignition.

 

Got a 181 here if you want me to test carb, coil on it. Would need posting, Northants.

 

Last thing, this range of saws are pretty mediocre on compression from new, I've found high comp engines are more tolerant to fueling being a little out of wack. Have you checked compression?

A little update on the MS181C I was having trouble diagnosing a misfire on.

 

I took @bmp01 up on his offer and finally got the saw to him on Friday. By the evening he had sussed out a number of faults, the coil gap way too large, purge bulb pipe not fitting properly and the biggy was the accelerator pump piston. By Saturday it was ready for collection with a modified carburetor and arrived back to me yesterday. Here it is cutting some wood immediately after running it 10 seconds from cold. I have now ordered some parts he suggested should be replaced before taking it back to the lady owner.

 

@bmp01 may explain the detail better.

 

https://drive.google.com/file/d/1EHPlbeW3aI717zcwEPn0wq9Gl2T0_Heo/view?usp=sharing

DRIVE.GOOGLE.COM

 

[bmp01]

On 30/03/2022 at 15:28, openspaceman said:

A little update on the MS181C I was having trouble diagnosing a misfire on.

 

I took @bmp01 up on his offer and finally got the saw to him on Friday. By the evening he had sussed out a number of faults, the coil gap way too large, purge bulb pipe not fitting properly and the biggy was the accelerator pump piston. By Saturday it was ready for collection with a modified carburetor and arrived back to me yesterday. Here it is cutting some wood immediately after running it 10 seconds from cold. I have now ordered some parts he suggested should be replaced before taking it back to the lady owner.

 

@bmp01 may explain the detail better.

 

https://drive.google.com/file/d/1EHPlbeW3aI717zcwEPn0wq9Gl2T0_Heo/view?usp=sharing

DRIVE.GOOGLE.COM

 

No worries, pleased to be able to help 

[Darkslider]

On 31/03/2022 at 17:03, bmp01 said:

No worries, pleased to be able to help 

How do you go about diagnosing an accelerator pump problem? I've had a few saws where everything else has checked out but it still bogs when revving so as a last resort I've fitted a new carb which has cured the problem, however it's always felt like a lucky guess so far I'd like to know for sure how to pinpoint an internal carb/pump fault?

[spudulike]

It gives different issues on different saws but generally a bad pump gives an idle that just rises in revs or fluctuates and dies without touching anything. Generally it makes the saw impossible to tune in the normal way and a solid idle is never achievable. 

 

On some saws and 4T kit, the symptom can be a poor pickup from idle with the engine stumbling if the throttle is cranked open suddenly.

[bmp01]

On 15/04/2022 at 10:10, Darkslider said:

How do you go about diagnosing an accelerator pump problem? I've had a few saws where everything else has checked out but it still bogs when revving so as a last resort I've fitted a new carb which has cured the problem, however it's always felt like a lucky guess so far I'd like to know for sure how to pinpoint an internal carb/pump fault?

A nice tell-tale, if you are prepared to do a bit of disassembly, is to drip some Redex into the accelerator piston hole behind the throttle shaft and see if you can suck it into the hi speed circuit. I tend to blank off the drillings in the metering chamber with blutack, remove hi speed screw and suck through there via soft tube. Any time you see red coming through the carb you know the accelerator piston seal is leaking.

Edited April 20, 2022 by bmp01
It was late when wrote this.... words added for clarity

[gand]

This was me today. Did about 200 altogether, all different length, pitch etc.

[Dan Maynard]

17 hours ago, gand said:

This was me today. Did about 200 altogether, all different length, pitch etc.

I looked above the bench and thought that's a lot of chain, then realised Stihl department was below and there's even more there!

[spudulike]

I am hoping you sell chain as you may have overstocked if you don't

[AJStrees]

Must have hit something hard on the wee Lumag chipper. One of the blades cracked. Was a bugger to get the fifth bolt out. Lots of heat, Impact Wrench and one of those turbo sockets got it out at last. 
 

Put a new set of blades on. Looking pretty peachy now. Runs a goodun. 

Edited February 16, 2023 by AJStrees