stihl 066 porting

[Deets066]

These saws had a pile of different carbs, I can't tell any performance change between any off them but I always put a 69 on my saws but I don't know why.
Fixed jet or not I don't care, I haven't ran out for fuel yet I'm still needing air!

If you grind to far it won't tune, it will run but have idle trouble.

The bore on a WJ 69 is .030 bigger than the 40 series Walbros

 

[jmssaws]

1122 has Got to be the easiest saw I've ever worked on. Can't say a thing about porting as that is not my thing, but wrenching on a 1122 is a joy. (running a 1128 is easier on my back though..)

I've got like the mechanic who won't work on ford's anymore, I turn down most every saw that isn't a 1122, I'll do 394/5s but I don't like many of the new saws, takes to big a box to hold the parts.

 

[drf256]

Jason,

When you grind out that Venturi, do you cap the main nozzle with something?

Is that nozzle removable? If so, how?

I was thinking of hogging out a WT194 for my next 026 build.

For those who use an 044 carb on the 026, which intake boot are you using?

 

[Redfin]

Jason,

When you grind out that Venturi, do you cap the main nozzle with something?

Is that nozzle removable? If so, how?

I was thinking of hogging out a WT194 for my next 026 build.

For those who use an 044 carb on the 026, which intake boot are you using?

Id like to add to that. You said dont grind to far, how far is that?

 

[drf256]

It would be nice to remove the nozzle and bore it out on the lathe.

 

[psuiewalsh]

I is the nozzel the same as the check valve? If so they press out. I have changed a couple that leaked.

 

[psuiewalsh]

http://www.arboristsite.com/community/threads/repairing-walbro-check-valves.269276/#post-5117319

 

[Keith Gandy]

I is the nozzel the same as the check valve? If so they press out. I have changed a couple that leaked.

How do u check for leak? Pull a vaccum on the high side? Check valve goes bad causes it to leak?

 

[Keith Gandy]

Okay . Sorry I posted before i saw the article. Thanks

 

[psuiewalsh]

page 15

 

[jmssaws]

Id like to add to that. You said dont grind to far, how far is that?

You can't grind it completely out but you can get close.

 

[David Young]

038 for the 026 some use 044

I have bored them both ways, with the nozzle left in and with them removed never a problem.

Boring them on a lathe sounds like a great idea but may uncover passages. where you can take meat may not be concentric.

I don't go into many carbs looking to make it bigger. I will go though and "melt" all the bumps and irregularity's, smooth the shafts, widdle down the screws.

I have also moved location of the main nozzle in and out.


If you haven't bored a carb I will let you know I have ruined a few, and expect that its possible that you will too just be careful.

David

Jason,

When you grind out that Venturi, do you cap the main nozzle with something?

Is that nozzle removable? If so, how?

I was thinking of hogging out a WT194 for my next 026 build.

For those who use an 044 carb on the 026, which intake boot are you using?

It would be nice to remove the nozzle and bore it out on the lathe.

 

[drf256]

038 for the 026 some use 044

I have bored them both ways, with the nozzle left in and with them removed never a problem.

Boring them on a lathe sounds like a great idea but may uncover passages. where you can take meat may not be concentric.

I don't go into many carbs looking to make it bigger. I will go though and "melt" all the bumps and irregularity's, smooth the shafts, widdle down the screws.

I have also moved location of the main nozzle in and out.


If you haven't bored a carb I will let you know I have ruined a few, and expect that its possible that you will too just be careful.

David

Is there any utility to leaving the venturi non-concentric?

As in leaving it on the bottom where the nozzle is, but removing at the top?

 

[Stihlbro]

Is there any utility to leaving the venturi non-concentric?

As in leaving it on the bottom where the nozzle is, but removing at the top?

You have to watch where the needle comes from pump side of carb. Easy to cut thru trying to make the bore concentric.

 

[Redfin]

K Jason. Ive never modded a carb and im looking at one off my 2100 im building. Im sure this thing could use more fuel. Doesnt fuel feed rely on the pressure drop past the venturi?

Looking from the jug out on this one do you grind from the smallest diameter in to where it stops the taper?

 

[MustangMike]

"Doesnt fuel feed rely on the pressure drop past the venturi?" Yes.

That is why it is there, I guess it will just work with "less" of it.

 

[jmssaws]

I can't speak for other saws but a ported 066/660 gains tremendous rpm in the wood with a hogged out carb,it barely changes the tune but you may have to fatten it up a touch.

I grind from the small side to the big side.

 

[mdavlee]

You don't want to have the whole venturi gone. You need a tiny bit of a reducer in there. Just not quite what they have to start with.

 

[Redfin]

I can't speak for other saws but a ported 066/660 gains tremendous rpm in the wood with a hogged out carb,it barely changes the tune but you may have to fatten it up a touch.

I grind from the small side to the big side.

You don't want to have the whole venturi gone. You need a tiny bit of a reducer in there. Just not quite what they have to start with.

Thank you both. Another question for now, what are the symptoms of a saw needing this? Does it run like one with a clogged filter?

 

[Deets066]

Thank you both. Another question for now, what are the symptoms of a saw needing this? Does it run like one with a clogged filter?

I've seen saws run great without boring the carb, but as Jason said they seem to hold more rpm in the wood.

I have not tried this yet, but have seen before and after vids from Jason