Echo cs 490 porting

[drf256]

Looks like nearly no Venturi Mike.

 

[drf256]

I'm a bit of an idiot with carbs.

Mike, can you explain what feeds what in the metering picture of your carb?

Is the main jet missing?

What feeds the Welch plug area?

 

[drf256]

Does any other brand bar interchange on an echo?

 

[Red97]

I'd be happy too. Quite respectable.

I never did any stock cuts. Pertly cause I wanted to dive right in, and mostly cause I wanted to finally work on a brand new saw.

We should come up with some readily available constant for cutting. Like a 6x6 yellow pine railroad tie.

I know it will cost a bit, and you can't burn the wood, but it would give us a constant. Maybe even 2 0r 4 strapped together.

Might be a way to get better comparisons of gains on the web.

Yeh my test log tapered a good inch if not more from the stock test cuts and bigger diameter for the ported test cuts.

Might have to track down some square pine cants. Do have a couple of large cotton wood logs could make a few 12x12 for all my carb testing.

View attachment 17422 View attachment 17423 View attachment 17424
I have a couple carbs I have done for 36cc saws.
This is a carb I built for a drop in big bore carb from a husky 136 and made it work for the echo 360t

Thank you, did that nozzle press right out? Any unwanted characteristics once you swapped it ?

 

[merc_man]

Does any other brand bar interchange on an echo?

Not 100%,but i think a husky bar will.

 

[Red97]

Does any other brand bar interchange on an echo?

Husqvarna small mount is easily modified to fit. Think you just have to grind the adjuster hole to the bottom of the chain groove for oil.

 

[Red97]

After looking at big timber prices at the box store, I'm gonna try some free hand milling..

(Edit)

Or 6 plain 2x12 strapped together may be in the budget.

 

[echoshawn]

I just put a standard echo mount (d176) 20" 3/8 bar on mine.
Seems to push enough oil through the adjuster hole on it.
I know it'll cut faster with low pro or .325, but I like having the same bar/chain combos on the majority of my saws. Poulan and Echo.
Hell, my only oddballs are my 268, 272, and dolmar 143.

 

[Backtroller]

Wonder if a K041 would fit? I have a new Orgeon 20" .325 .050 you could play with.

 

[bikemike]

Yeh my test log tapered a good inch if not more from the stock test cuts and bigger diameter for the ported test cuts.

Might have to track down some square pine cants. Do have a couple of large cotton wood logs could make a few 12x12 for all my carb testing.



Thank you, did that nozzle press right out? Any unwanted characteristics once you swapped it ?

This fuel nozzle came out easy in this carb. Some of the check style nozzle don't come out as easy. But a dremel can work around a nozzle too with the diamond coated tooling Iil post a pic of 1 I did without pulling the nozzle
Echo 360t stock before
After This is the stock echo carb that is on my top handle everyday runner. It seams to like it and it don't suck the fuel down fast. There was no porting to the engine. Just some intake filter adapter work and a few holes in the filter cover to keep filter box from getting filled with chips, and the muffler is totally gutted with maybe a 1/8 inch bigger exit hole

 

[bikemike]

I just put a standard echo mount (d176) 20" 3/8 bar on mine.
Seems to push enough oil through the adjuster hole on it.
I know it'll cut faster with low pro or .325, but I like having the same bar/chain combos on the majority of my saws. Poulan and Echo.
Hell, my only oddballs are my 268, 272, and dolmar 143.

Well if you did go to a 325 I'd run a 8 pin cause of torque and the 7 pin 325 is small vs 7 pin 3/8 so lot less fps chain speed

 

[Backtroller]

Does anyone know if those echo models listed similar are similar to the 490? If so K041 looks like it's another choice

 

[Red97]

Does anyone know if those echo models listed similar are similar to the 490? If so K041 looks like it's another choiceView attachment 17434

If I remember right, K041 and k095 adapt fairly easy, so that bar should fit the 490, maybe just minor oil hole adjustments.

 

[bikemike]

If I remember right, K041 and k095 adapt fairly easy, so that bar should fit the 490, maybe just minor oil hole adjustments.

I have modified bars to work on other saws just to use em. As long as they fit studs and tension pin , oiler port is easy

 

[merc_man]

Ok will be down in few

 

[drf256]

About to start playing carb. Snotty weather here.

 

[bikemike]

About to start playing carb. Snotty weather here.

Good keep us posted

 

[drf256]

Thoughts on the tiny slot that feeds air to the air box from the flywheel area?

 

[bikemike]

Thoughts on the tiny slot that feeds air to the air box from the flywheel area?

I would just ad holes to filter cover or not use the filter cover flip the saw over and the crap falls out

 

[drf256]

Ok. Took my stab at the carb today. Got some measurement pics and some advice on what NOT to do.

Intake boot measurement 16.46mm

Throttle bore 15.83

Venturi bore opening 18.77

Venturi 13.49

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