Echo cs 590,600,620 porting/mod/build thread

[Locust Cutter]

I love the staccato idle of that saw, it's mean! I looks like it picked up VERY well!

 

[mdavlee]

How far is the timing advanced or is it?

 

[Red97]

Where did you find the RPM?

Echo 670 carb. Same venturi as the 590.

How far is the timing advanced or is it?

Stock 620 specs, wanna say 32* total,

You hear something?

 

[Four Paws]

So, why did the 670 carb help improve performance when it was the same size?

 

[mdavlee]

Echo 670 carb. Same venturi as the 590.



Stock 620 specs, wanna say 32* total,

You hear something?

In that one video with all the fuel and 4 stroke it almost sounded like a pinging. I'd try to retard it some more. Sometimes too much advance fights rpms as well as too little

 

[Red97]

So, why did the 670 carb help improve performance when it was the same size?

No high side bypass.

Both my 590 and brand new 620 carb can't be leaned out even with the H closed off. It needed leaned out. Even the 620 wouldn't go past 13500 pig rich h closed off.

In that one video with all the fuel and 4 stroke it almost sounded like a pinging. I'd try to retard it some more. Sometimes too much advance fights rpms as well as too little

Could I add more gap? To get a couple degree?

 

[mdavlee]

No high side bypass.

Both my 590 and brand new 620 carb can't be leaned out even with the H closed off. It needed leaned out. Even the 620 wouldn't go past 13500 pig rich h closed off.





Could I add more gap? To get a couple degree?

That would be a quick easy way to try a little less.

 

[Red97]

That would be a quick easy way to try a little less.

Probably is a bit tight, I just eyeballed it putting it back on.

Really wish I would have put some compression in this saw

 

[Four Paws]

No high side bypass.

Both my 590 and brand new 620 carb can't be leaned out even with the H closed off. It needed leaned out. Even the 620 wouldn't go past 13500 pig rich h closed off.

Could you plug it with some JB weld or solder?

 

[Red97]

Could you plug it with some JB weld or solder?

It needs to be restricted. Plugging is a no go. Tied into both high and low side. May try some jb on my extra 590 carb. But I knew this one would get the job done.

 

[Red97]

100% stock, same chain etc

Ok, still haven't kitted the carb, but got some run time on this thing. turning into quite the ringer.... It may even benefit from the cs 8000 carb....

Outran both of my 670/6700's... even with the 32"

Yeh that is some soggy hikory, but this was 5-6 seconds quicker than the 670/6700.



Think it could benefit from some more compression....

 

[Majorpayne]

100% stock, same chain etc

Ok, still haven't kitted the carb, but got some run time on this thing. turning into quite the ringer.... It may even benefit from the cs 8000 carb....

Outran both of my 670/6700's... even with the 32"

Yeh that is some soggy hikory, but this was 5-6 seconds quicker than the 670/6700.



Think it could benefit from some more compression....

Which saw is this Joe!

 

[Red97]

Which saw is this Joe!

The ported 590 in this thread. Unlimited 620 coil, and a 670 carb, same size bore/venturi but I can lean it out where needed.

 

[Hedgerow]

Good thinking outside the box on the carb thing Joe.

 

[Red97]

Good thinking outside the box on the carb thing Joe.

Thank you,

May try fiddling with the stock carb. Sure would be nice to "mod" vs finding a replacement.

 

[Poleman]

Red, I'm going to get into my 620 carb... I hope this weekend and see if I can get more rpm's. Mines like yours and not wanting to go past 13,5k....when it needs to be around 14,4k I'm thinking. Never looked inside one of these but will keep you posted! I really need more rpm's to make this good saw a GREAT saw.

 

[Red97]

Red, I'm going to get into my 620 carb... I hope this weekend and see if I can get more rpm's. Mines like yours and not wanting to go past 13,5k....when it needs to be around 14,4k I'm thinking. Never looked inside one of these but will keep you posted! I really need more rpm's to make this good saw a GREAT saw.

Sweet, feel free to use this thread if you wish.

Not up on my carb terms. But I think the issue is a rather simple fix. Reduce the size of a hole. Lol

On the metering side, where the high/low needles let the fuel in both enter in the same spot bout .060 diameter holes, think if you could reduce the high side by half it would lean out like it is supposed to.

Tried it with a piece of tygon... it worked, but was the low side lol...

I'll try and take some detailed pics tomorrow.

 

[Poleman]

Thst would be super...then I could see what's going on and get ideas!!
Thanks!!!

 

[Red97]

Thst would be super...then I could see what's going on and get ideas!!
Thanks!!!

I'm hoping we can figure something out this new 620 carb is a mighty expensive paper weight lol

 

[Poleman]

Ya, I've done a couple 590's and was wondering if the carb would help or the coil more........thinking the coil as the carb had it running so rich....even with H closed.
Thought maybe I was crazy but your results are pretty much the same as mine.