ms880 clone

[LoneOak]

Wow, what a coincidence! last week, my 880 also developed a very similar issue "lean condition" like symptoms. So far I have striped the carb down and removed the welch plug but did not remove the bleeder jet that protrudes in to the venturi. I found quite a bit of milling swarf under the fuel inlet screen and under the welch plug. The glue used to seal the welch plug was also starting to dissolve and "cake up".

Unfortunately I did not get to the camera soon enough to document the full amount of trash flushed from this carb.

After all of this, the saw still exhibits a lean condition and no amount of needle adjustment will correct it.
I have ordered a new Carb, it will be here tomorrow.


I am going to test saw for air leaks again, and this time the carb will be included in the leak test.

 

[mirage]

Thanks Mr Oak for the info. I just ordered the same carb. Please let me know if this takes care of your problem.

 

[LoneOak]

TL;DR.....the saw runs perfectly!!

Some details,
While testing for leaks, I did find a leak at the intake boot where the clamp pinches together. Added a few twists to the clamp screw and leak is gone, test run the saw and it still will not throttle up with out flaming out (acting lean). And now being absolutely confident that there are no air-leaks, I swapped to the new "OEM" carb. After some minor adjustment to the needles the saw is operating flawlessly!
A nice off-idle bark and rapidly settling to a perfect stable idle.

It purrs like an angry kitten!

 

[mirage]

NICE. Thank you for the info. Can't wait till my carb gets here.

 

[mirage]

Hay Mr Oak could you tell me the adjustments you made to the new carburetor?

 

[LoneOak]

Hay Mr Oak could you tell me the adjustments you made to the new carburetor?

Yes!

I installed the carb just as it was right out of the box and the saw fired right up, but I did have to make some adjustment to the high and low speed needles as well as the idle screw.
The low speed needle was opened about 1/2 turn from its' factory setting.
The high speed needle was opened about 3/4 of a turn from its' factory setting. But have not yet had the saw in wood to make a final adjustments.
The idle screw was turned in (clockwise) 1/2 a turn.

My saw currently has very little time on it, so I would assume that these adjustments may be reversed by the time the saw hits about 10 to 15 hrs of use.

 

[afleetcommand]

Anyone actually using one of these?

 

[Jason628]

Anyone actually using one of these?

My stock as a farmertec box 660 is overkill for most of the cutting I do but, I want one of those 880 clones just to have one... I did get to play with an 881 but, I wasn't really impressed given that the saw cost over $2000. I mean it's a beautiful saw but, $$$. Ryan was a little butt hurt when my 660 clone was consistently 3 seconds faster than his 881 through this log. What Ryan doesn't know is a change in gearing and he would have smoked me...

 

[mirage]

Does this carb come with tamper proof adjustment screws?

 

[LoneOak]

Does this carb come with tamper proof adjustment screws?

There are limiter caps on the screws, but they are regular flat head screws. And the caps can be removed easily since they are fitted only 1/2 way on the screw.

 

[mirage]

How do I remove the tamper proof on the screws. Just do want to dig around in there. Thanks

 

[Jason628]

How do I remove the tamper proof on the screws. Just do want to dig around in there. Thanks

Wood screw and a pair of pliers

 

[LoneOak]

Well, the carb I received had the caps already halfway out. Just grab any pliers pull'em off.

 

[Jason628]

Stihl special tool part# 59108904501

 

[mirage]

Got the new carb installed. The idles great. I set the carb to Mr Oak suggestion. Just had to turn down the low side a little bit. I got a bark box on this thing.

 

[LoneOak]

Got the new carb installed. The idles great. I set the carb to Mr Oak suggestion. Just had to turn down the low side a little bit. I got a bark box on this thing.

Is it loud with the BarkBox?
I only modestly mod'ed the muffler on my saw and it is quite a bit louder and very "Poppy".

 

[mirage]

Holy smokes it is loud