Carb Guru? WJ-69 and Clone comparison

[jmssaws]

I have several carbs that when tuned right they idle way to fast,how is this fixed?

 

[jmssaws]

Especially on saws with big ignition advances in have trouble getting it tuned clean at a low enough rpm to keep the chain from coasting

 

[junkman]

I have several carbs that when tuned right they idle way to fast,how is this fixed?

too bad the needles are not like dirt bikes

 

[srcarr52]

I have several carbs that when tuned right they idle way to fast,how is this fixed?

Set the idle at your ideal RPM and then pull the carb off and look at the butterfly, if it's open too far make the bypass or cutout larger.

 

[junkman]

Especially on saws with big ignition advances in have trouble getting it tuned clean at a low enough rpm to keep the chain from coasting

My hybrid likes a lean lh screw for throttle response ,but i have to set it closer to 1 turn out to idle ,if i set it to idle for about 20 seconds and die ,it runs good ,but not good for working if set it down a lot . ,do you have brand new clutch or old one on the saw that is spinning ?

 

[jmssaws]

Set the idle at your ideal RPM and then pull the carb off and look at the butterfly, if it's open too far make the bypass or cutout larger.

With the butterfly shut I still have a idle over 3k unless I fatten the low way to far.

 

[jmssaws]

My hybrid likes a lean lh screw for throttle response ,but i have to set it closer to 1 turn out to idle ,if i set it to idle for about 20 seconds and die ,it runs good ,but not good for working if set it down a lot . ,do you have brand new clutch or old one on the saw that is spinning ?

I've had that problem for years on many saws,there's 4 saws here now that will idle to fast and can only be slowed down by a very fat low jet,I would love to know how to fix it. I know a saw as far as these are won't idle at 2500 like stock but 3k+ is silly.

 

[jmssaws]

This look right?
I'm holding the butterfly open

 

[junkman]

On cars with long duration cams sometimes a hole in the plate smooths out the idle some ,not sure if would do same on a saw or not ?

 

[srcarr52]

On cars with long duration cams sometimes a hole in the plate smooths out the idle some ,not sure if would do same on a saw or not ?

Have to do that on Holleys when they don't have air bleeds. Put a hole in the butterfly so you can back the screw down so the butterfly is in the sweet zone of the idle fuel slot in the baseplate.

 

[srcarr52]

This look right?
I'm holding the butterfly openView attachment 29037

I'd see if I could turn it to where the cutout is lined up directly over the hole.

 

[jmssaws]

I'd see if I could turn it to where the cutout is lined up directly over the hole.

So I want it lined up with the hole that's behind the butterfly by the nozzle?

 

[srcarr52]

So I want it lined up with the hole that's behind the butterfly by the nozzle?

Yes.

 

[jmssaws]

Yes.

The bevel on it won't allow it to fit the bore snug,or does it not matter?

 

[srcarr52]

The bevel on it won't allow it to fit the bore snug,or does it not matter?

It's important to fit in the bore nicely. Just get it as close as possible to over that hole and give it a shot. Did it have the notch in butterfly or did you cut that in?

 

[Mastermind]

I like to see the notch directly behind the idle hole. I'm just trying to be sure we are all on the same page.....

 

[srcarr52]

I like to see the notch directly behind the idle hole. I'm just trying to be sure we are all on the same page.....

Behind? All a matter of reference and which hole?

Anyway, IMO the hole that should be almost covered by the butterfly when closed should have the notch lined up with it.

 

[Mastermind]

I'm referring to the outermost hole. I think of that as the idle hole, and the ones further back in the carb as the transition holes.

So, the relief in the butterfly plate should be lined up with the idle hole......not necessarily with the transition holes.

Wow........I think I confused myself. lol

 

[jmssaws]

It's important to fit in the bore nicely. Just get it as close as possible to over that hole and give it a shot. Did it have the notch in butterfly or did you cut that in?

That is a real wj69,I've got a dozen or more and none of them are in line with that hole.

 

[jmssaws]

Every carb I have the notch is in line with the hole closest to the intake boot not the hole by the nozzle