Diagnose an idle problem for me

[Haywire Haywood]

I was out cutting with my 346 yesterday and it started idling funny. RPMs would go up and down at idle till it would finally die. It would then restart with one pull of the rope. It seemed to cut fine, it just wouldn't idle for more than about 30 seconds.

Ian

 

[RiverRat2]

sounds as though yer possibly chasin an air leak???

I was out cutting with my 346 yesterday and it started idling funny. RPMs would go up and down at idle till it would finally die. It would then restart with one pull of the rope. It seemed to cut fine, it just wouldn't idle for more than about 30 seconds.

Ian

:bang: :bang: :bang:

 

[ChuckinOhio]

I was out cutting with my 346 yesterday and it started idling funny. RPMs would go up and down at idle till it would finally die. It would then restart with one pull of the rope. It seemed to cut fine, it just wouldn't idle for more than about 30 seconds.

Ian

How new is it Ian? Is it going through the "Break in run" of say 5 to 10 tanks ?

I had a similar problem with my 350 when it was new and running in, it required richening up the low speed a tad and readjusting the idle and it smoothed out.


Chuck

 

[Haywire Haywood]

New this thing isn't... it's about 7 years old and on it's second set of rings. I kinda burned it up once messing with the high speed jet before finding AS.

The fuel lines are originals, I'll have a look at them for cracks.

I'll play with the carb too and see if richening it a little has any effect.

Ian

 

[RiverRat2]

Pressure/vacuum test

New this thing isn't... it's about 7 years old and on it's second set of rings. I kinda burned it up once messing with the high speed jet before finding AS.

The fuel lines are originals, I'll have a look at them for cracks.

I'll play with the carb too and see if richening it a little has any effect.

Ian

Mannys right simple stuff,,, remove fuel filter and pressure test to inlet valve on carb, it should hold pressure!!!

 

[manual]

look closer

New this thing isn't... it's about 7 years old and on it's second set of rings. I kinda burned it up once messing with the high speed jet before finding AS.

The fuel lines are originals, I'll have a look at them for cracks.

I'll play with the carb too and see if richening it a little has any effect.

Ian

The fuel line breaks by the tank or inside it.
That would be my first step.

 

[Al Smith]

One often overlooked thing is the position of the carb butterfly.Certain models are held in position by a tiny little philips head screw.Once in a blue moon these things loosen up and allow the butteryfly to shift positions.

The butterfly has a tiny little notch that must be positioned directly in line with the low speed jet or else it will not idle at all,just flat out dies.

I would hate to make a guess as to how many carbs have given me fits in the past before Rocky J Squirrel brought this to my attention.

 

[RiverRat2]

YOU MEAN Bullwinkles Buddy????

I would hate to make a guess as to how many carbs have given me fits in the past before Rocky J Squirrel brought this to my attention.

 

[Cut4fun]

Ian, check your fuel lines.
I just had to chase down a cracked line yesterday on a 1800. One was where mine went through handle and one in the tank where it went through tank. Same thing was happening as yours, noticed it wouldn't idle during use. Put a new line and fuel filter while I was at it, runs good as new again. Good luck.

 

[Al Smith]

I don't know much about old Bullwinkle but Rocky J is a climber/treeman in Florida .

 

[manual]

One often overlooked thing is the position of the carb butterfly.Certain models are held in position by a tiny little philips head screw.Once in a blue moon these things loosen up and allow the butteryfly to shift positions.

The butterfly has a tiny little notch that must be positioned directly in line with the low speed jet or else it will not idle at all,just flat out dies.

I would hate to make a guess as to how many carbs have given me fits in the past before Rocky J Squirrel brought this to my attention.

Thanks Al. good tip

 

[SawTroll]

... I would hate to make a guess as to how many carbs have given me fits in the past before Rocky J Squirrel brought this to my attention.

It is a pity he isn't here any more, interesting guy, and knowledgable also!!!

 

[Pile It]

Just for kicks you could also check carb mounting bolts for tightness or possible leaks in that neighborhood.

 

[Hard Knocks]

How is the tank vent and fuel filter? Have you tried loosening the gas cap enough to vent and letting it idle?

 

[Haywire Haywood]

Haven't tried anything yet, just packed it back in the barn for now amongst the other two saws that are in various states of disassembly.

Ian

 

[lxt]

some models had a carb. screen inside by fuel inlet, check this if all else fails, dirt under the needle seat? I usually remove my carbs periodically on saws not needing to be used & clean them, this has reduced alot of on job problems for me. A pain but worth it!! Good Luck.

LXT.........

 

[RiverRat2]

Good post Al!!!!

One often overlooked thing is the position of the carb butterfly.Certain models are held in position by a tiny little philips head screw.Once in a blue moon these things loosen up and allow the butteryfly to shift positions.

The butterfly has a tiny little notch that must be positioned directly in line with the low speed jet or else it will not idle at all,just flat out dies.

I would hate to make a guess as to how many carbs have given me fits in the past before Rocky J Squirrel brought this to my attention.

I tried to rep ya but Im out of bullets,,,,You just got moved to the head of the class!!!!!

 

[Al Smith]

I tried to rep ya but Im out of bullets,,,,You just got moved to the head of the class!!!!!

Awe shucks,'taint no big deal .Just passing on info and staying under the radar.