Lean or rich high end bog?
- Thread starter Vintage Engine Repairs
- Start date
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chainsawchap
ArboristSite Operative
hey tom the saw seems lean to me be carefull I am the chainsaw chap still learning but a saw should 4 stroke bllippp bliiippp blippp it should blow smoke running rich will keep the saw running well for decades if you take care of the air filter and keep saw dust out of the gas. 4 stroking on a rich mixture will actually cool down the cylinder its hard to understand but makes sence you are putting more fuel on the cylinder that is hot. oil is thicker than gas which is refined oil to my knowledge.
your saw aint working right what you have there a stihl 025? I think your saw needs tuned better or you might have a air leak somewere. be carefull running that saw like that it should always blow smoke that way you no your safe. a saw should 4 stroke due to it isn't under a load until you put it into a tree which would work the tool and lean it out some to compensate for the rich mixture.
keep up the good work tom and good luck with your saw.
your saw aint working right what you have there a stihl 025? I think your saw needs tuned better or you might have a air leak somewere. be carefull running that saw like that it should always blow smoke that way you no your safe. a saw should 4 stroke due to it isn't under a load until you put it into a tree which would work the tool and lean it out some to compensate for the rich mixture.
keep up the good work tom and good luck with your saw.
Hey champ
thanks for your time and message! No leaking anywhere as I pressure and vacuum tested it. It’s ms 180 genuine Zama carb with aftermarket top end (piston rings and cylinder. (Carb is genuine Non adjustable Zamma C1Q)My new ms 180 works beautifully without needing adjustment. I think it’s the top end being rubbish and poor transfer port timing! I’m not sure though
chainsawchap
ArboristSite Operative
oh this is one them self tuning carbs? if that's the case im not really sure bud. stihl 180 I need to invest in a pressure tester to up my game and take the guessing game out of fixing a saw.
chainsawchap
ArboristSite Operative
do you have the right plug in the saw sometimes the wrong plug can make a saw run like crap I sujest mike acress the chainsaw collecter corner this sight has a lot of helpful info to the saw enthusiast. chainsaw collector corner check it out some time if you find some extra time.
No no, just fixed jet
chainsawchap
ArboristSite Operative
Check the gap hum no adjustment carb how much time is on your saw?
chainsawchap
ArboristSite Operative
Check the cylinder for the chrome plating gone o can't strive enough don't buy China junk unless it's a egg roll. That might be your problem China cylinders arnt made to last I would year down the saw did you replace the bearings and crank seals when you put the cylinder kit on did the saw ever run right before the new China cylinder?
I don’t fully understand your question / comment, but the saw was 30 Aussi dollars and not working. Cleaned it up and put back together to check. Ran with low compression and tricky to start, but it did and rev’d fine. Put new top end and cylinder from China in knowing I was taking a risk but the saw was so cheap anyway and this is the result. Not sure if it’s too lean or too rich or if it’s a transfer port timing issue
chainsawchap
ArboristSite Operative
When u put the top end on did you put new seals in the case?
Yes
and tested pressure and vacuum holds good!chainsawchap
ArboristSite Operative
Did you pressure test fuel lines for holes
chainsawchap
ArboristSite Operative
Does saw have ruber intake boot
John Stryker
ArboristSite Operative
It sounds to me like it's starving for fuel. You say the crankcase passed a pressure/vacuum test. So, I would start with checking the tank vent, fuel line (could be collapsing under vacuum), filter, and carb inlet control lever setting (should be flush with carb floor, I think, depending on which carb).
I hope you get it figured out.
I hope you get it figured out.
I haven’t as the line is new, but I will just in case
Thank you! Carb metering lever is correct as I checked it with a Zamma metering gauge. Filter and line are new, but will check for pin holes
Fuel line holds pressure (it’s new and OEM stihl) filter is new too. Breather is working good too.
sunfish
Fish Head
Chinese food good, saw parts not so much.
