Huztl MS660

[Johnnybar]

All, There are some subjects I personally would be lost on as I am sure we all could be, depending on the topic. I want to thank all of you here as well as other fellow forum members for the wealth of information you all provide...THANKS!!!!!!

Bedford, Your initial note to Salas at Walbro did not indicate whether you were able to reach a proper tune or a rich tune with the .69 jet or not. Salas assumed you were not able to get past a lean condition with the original .69 jet and provided the positive reply about the .76 jet helping your situation. Salas was not given the whole story, as was given here on the forum, about the saw being tunable with the original .69 jet. "The devil is in the details" and that statement definitely fits this situation.

Keep on Sawing!

 

[Bedford T]

To help you, the subject was changing the jet size to the better lube and make cooler. So he had a the info. The email was carefully worded and it was a line of thinking on a larger carb size. But thanks for your input.

 

[blsnelling]

A=L needle fuel
B= Fixed jet fuel
C=H needle fuel
D= The total fuel needed for a correct tune set WOT

A+B+C= D
5+10+10=25
5+15+5=25

As in the example above, the only thing you're doing with a larger value for B is requiring a smaller value for C. You have not changed D at all.

 

[blsnelling]

All, There are some subjects I personally would be lost on as I am sure we all could be, depending on the topic. I want to thank all of you here as well as other fellow forum members for the wealth of information you all provide...THANKS!!!!!!

Bedford, Your initial note to Salas at Walbro did not indicate whether you were able to reach a proper tune or a rich tune with the .69 jet or not. Salas assumed you were not able to get past a lean condition with the original .69 jet and provided the positive reply about the .76 jet helping your situation. Salas was not given the whole story, as was given here on the forum, about the saw being tunable with the original .69 jet. "The devil is in the details" and that statement definitely fits this situation.

Keep on Sawing!

This guy gets it!

 

[Bedford T]

This guy gets it!

He could not read it either

 

[Bedford T]

Here forward direct all technical questions to Brad instead of asking walbro.

Obviously walbro lacks the knowledge. You will be insulted if you don't consult with brad

 

[blsnelling]

Here forward direct all technical questions to Brad instead of asking walbro.

Obviously walbro lacks the knowledge. You will be insulted if you don't consult with brad

Go back and read Johnny's post until you comprehend it. Until you do, this situation is futile.

 

[Johnnybar]

Bedford, In your email to Salas, you specifically stated, "thinking the extra fuel I could tune with would help". That statement implies previously you could not tune without the extra fuel. Please understand the fact that Salas had to assume you were too lean originally.

Make Chips Boys!

 

[Bedford T]

That relates to jet size...Would help me keep my engine more lubricated and cooler along with my fuel mixture...Is this a correct way of thinking.

Yes

 

[Bedford T]

I have started milling...The carb jet was .69 changed to .76 thinking the extra fuel I can tune with would help keep my engine ...

No where does more information come into play.

Was that a correct way of thinking yes was the answer.

 

[Johnnybar]

That relates to jet size...Would help me keep my engine more lubricated and cooler along with my fuel mixture...Is this a correct way of thinking.

Yes

"more lubricated and cooler" than what? A perfectly tuned originally jetted saw is what Salas never new about and the forum did.

 

[Wood Chopper]

This may not be the right time to ask but am I correct to assume that the "B" jet is tuned incrementally with the high speed screw until it's either fat or lean in the cut? Back in my KTM dirt days when it was hot and humid I decreased the main jet if it was cold and dry went a little bit bigger along with your needle clip position/taper. The idle jet you could turn the screw in or out until you ran out of low and adjustment then the jet would have to change.


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[TreeJoe]

I read it like it says it is about the jet size. It seems to be well worded and the answer is clear. I looked up carb jet and it was just like I thought. I will speak up and say good job @beford t

"A carburetor jet is a tiny hole in the venturi, which is the narrow end of a carburetor tube. The carburetor jet is an essential component of an internal combustion engine. This portion of the carburetor is the part that is responsible for allowing fuel to be drawn into combustion chambers, also known as cylinders."

So he changed the jet size to increase the flow of fuel and the benefits that come with that. Looks like you guys are beating up on him for nothing.

 

[mdavlee]

If you could tune the saw to 12k or whatever it was pig rich with the original jet it don't matter how big it is now. All you did is change where the H screw sits for a certain rpm.

 

[Johnnybar]

99.9% to 100% of stock saws will not benefit from a jet increase and I believe that some friends here on the forum are trying to make sure the average joe that might do a google search and stop by for a read understand the details of the decision on jetting.

 

[blsnelling]

This may not be the right time to ask but am I correct to assume that the "B" jet is tuned incrementally with the high speed screw until it's either fat or lean in the cut? Back in my KTM dirt days when it was hot and humid I decreased the main jet if it was cold and dry went a little bit bigger along with your needle clip position/taper. The idle jet you could turn the screw in or out until you ran out of low and adjustment then the jet would have to change.


Sent from my iPhone using Tapatalk

The fixed jet in discussion here is not adjustable. The fuel from the H needle is in addition to that from fixed jet.

 

[blsnelling]

99.9% to 100% of stock saws will not benefit from a jet increase and I believe that some friends here on the forum are trying to make sure the average joe that might do a google search and stop by for a read understand the details of the decision on jetting.

Exactly.

 

[Johnnybar]

This may not be the right time to ask but am I correct to assume that the "B" jet is tuned incrementally with the high speed screw until it's either fat or lean in the cut? Back in my KTM dirt days when it was hot and humid I decreased the main jet if it was cold and dry went a little bit bigger along with your needle clip position/taper. The idle jet you could turn the screw in or out until you ran out of low and adjustment then the jet would have to change.


Sent from my iPhone using Tapatalk

Most bike carbs operate on a sliding air valve that also variably meters fuel using a long tapered needle and can't be compared to saw carbs that have independent butterfly air control and fixed fuel delivery during operation.

 

[Johnnybar]

Dinner bell is ringing guys so my last word for awhile: If it will run...go make chips!

 

[Mattyo]

The walbro techs comment was vague at best...and seems to infer that more fuel is good for milling....not necessarily that a larger jet is the answer to more fuel. I'm with Brad...if you need more fuel....open the needle a bit. I'll take it one further. On these saws...its doubtful that you will run out of needle...therefore...no need for a larger jet.