No need to try to complicate things with a pile of technical garb, these Echo saws run real good when tuned right which not very hard to do. Plenty of vids on youtube with them cutting right with or really close to real good Husky and Stihl saws . This aint rocket science ,its a chainsaw. Steve
Echo 590 Timberwolf "H" setting
- Thread starter hatfield
- Start date
Help Support Arborist Forum:
No need to try to complicate things with a pile of technical garb, these Echo saws run real good when tuned right which not very hard to do. Plenty of vids on youtube with them cutting right with or really close to real good Husky and Stihl saws . This aint rocket science ,its a chainsaw. Steve
Chris-PA
Where the Wild Things Are
Nothing I wrote had anything to do with how well they run, it was about how the H setting works - which was the topic of the thread. It's almost a fixed H jet carb, only a small adjustment range is provided. If you make any changes like a muffler mod you may be moving outside the provided adjustment range.
These is NO problem tuning these saws anywhere between rich to lean with muff mod, do you have one? Steve
Chris-PA
Where the Wild Things Are
I realize you're an Echo fanboy and take offense at everything you feel is not a complement to them, but this was a simple discussion of how the carbs work. Echo is not the only one restricting the adjustment range in this way. It's a simple fact that they have provided a very small adjustment range for the H. That's probably OK for the stock saw and all Echo was required to do, but with mods that enrich the mixture you can easily run out of adjustment and be unable to lean it enough.
- A muffler mod makes the mixture richer.
- High temps mean you need to lean it some.
- Porting can improve air velocity and make the mixture richer.
And no I don't own one - why would I when I have my Chinese G621 clone.
I realize you're an Echo fanboy and take offense at everything you feel is not a complement to them, but this was a simple discussion of how the carbs work. Echo is not the only one restricting the adjustment range in this way. It's a simple fact that they have provided a very small adjustment range for the H. That's probably OK for the stock saw and all Echo was required to do, but with mods that enrich the mixture you can easily run out of adjustment and be unable to lean it enough.
Add some of that together and you run out of adjustment.
- A muffler mod makes the mixture richer.
- High temps mean you need to lean it some.
- Porting can improve air velocity and make the mixture richer.
And no I don't own one - why would I when I have my Chinese G621 clone.
Pure bs again Poulan fanboy. If you actually knew anything you would know that series Echo has plenty of adjustment to make them run rich or lean with a muff modd. I like any good saw, not cheap Poulan crap that I wont even work on as they wont hold a tune for more than 20 minutes. Steve
Chris-PA
Where the Wild Things Are
So a guy that admits he can't tune a saw assures us that a carb designed with a vary narrow range of adjustment can in fact be adjusted for anything, because since it's an Echo it is somehow magic. As this appears to be a faith-based discussion rather than a technical one, I'll leave you to it....
If you could read I said a crappy Poulan wont hold a tune, my other saws only need to be tuned for temp changes or a change in fuel. Steve
Red have you done this? Can you provide a part number for the replacement nozzle that you used? One gent told me he seals the HDA-268 walbro (with the semi fixed jet) with a dab of sealer on the bottom but I was kinda skeptical if I would be able to get it without sealing up the whole thing. If the nozzle from the HDA-191/199 will fit I would like to try it. Also, what do you plug the metering chamber access to the original semi fixed jet nozzle with - a spare brass plug?
I don't have a part number for the nozzle, but it was a direct fit from the hda 191. I'm sure most hda 19x carbs use the same nozzle.
You can see the hole in the brass nozzle. That is what needs to be closed off. The 191 nozzle dosent have that hole. Or you could use a dab of jb weld.
I fought with these carbs for weeks on my ported 590, pig rich with the H needle closed all the way. I finally swapped a hda 203 (off of a echo 670) that allowed me to tune where the saw wanted. Wanted to avoid having to buy a old carb for every 590.
With the modified 590 carb I am roughly 7/8 out @14,200
Started looking at the difference between the stock 590 carb and the 670 carb. Only major difference was the hole in the bottom of the main nozzle.
I would not recommend trying to remove and re install the 268 nozzle. I had one feed hole that has to line up exactly with the H feed in the carb body. Where the 191 nozzle has 2 feed holes in the side, and a machined band allowing flow, regardless of how it is installed.
Hi Red,
Thanks for the pic. What my problem is, is I have an HDA-268 which is leaking air into the nozzle at the top. Walbro wont sell a replacement nozzle saying buy a new carb for $85. Im trying find a suitable nozzle w/o the semi fixed jet which will fit. Do you know If the parts from the HDA-191/199 will fit? Appreciate the help.
Thanks for the pic. What my problem is, is I have an HDA-268 which is leaking air into the nozzle at the top. Walbro wont sell a replacement nozzle saying buy a new carb for $85. Im trying find a suitable nozzle w/o the semi fixed jet which will fit. Do you know If the parts from the HDA-191/199 will fit? Appreciate the help.
Sounds like the check valve got dislodged.
Yes I pressed out the nozzle from the 191, and installed it into the 268, just a few taps. Seems to be working great.
Perfecto, that is exactly what I needed to know.
Where you looking for an Echo 8000 muffler?
Where you looking for an Echo 8000 muffler?
Big Block
WFO or I don't go
Big Block
WFO or I don't go
Sounds healthy. Pulls that 32 really good.
sawfixer
ArboristSite Lurker
I just happened to see this posting after I've been having problems tuning my CS600P with the Walbro HDA-268 carb after a muffler mod. It's way too rich even with the high speed jet seated and has less power than without the muffler mod, which is a little disappointing. I was able to locate the main jet Walbro PNs of 112-3057 (.54) for HDA-196 and 112-3074-1 (.55) for HDA-198 but couldn’t find any main jet PN for HDA-191. I agree with Red97 in that it's better to replace the carb with a non semi fixed jet carb like the HDA-203 than to remove the jet and deal with the fuel feed hole alignment. I would also like to know if there are other HDA models which would be a direct fit for the CS590/600 saws. It looks like you can get a new HDA-191 on Ebay for $43/shipped but I don't know if it will fit. This is a lot cheaper than the HDA-316 and HDA-327 used on the CS620 without a semi fixed jet.
The jet out of the 198 is easiest. all you have to do is set the depth right. Don't have to worry about the feed hole like the stock jet.
The hda 316 I have still has the hole in the jet. Only difference is the bigger venturi.
The L needle way on the fat side will limit the max rpm. Should be able to get 12,500 easy enough.
The hda 316 I have still has the hole in the jet. Only difference is the bigger venturi.
The L needle way on the fat side will limit the max rpm. Should be able to get 12,500 easy enough.
sawfixer
ArboristSite Lurker
Thanks for your help. I will go with the HDA-191 jet but I have another idea, assuming the goal is to block or close this hole in the jet. Since the current HDA-268 jet has a .58 mm opening which equates to .022835 inches, I could use a 0-80 2A screw with a maximum minor diameter of .0442 inches and effectively plug the hole. This would eliminate having to swap out jets and I've found JB weld doesn't hold up in constant gasoline contact. Since the jet is made from brass, a short 0-80 screw should easily thread into the hole.
