Simplified---Adding A High Speed Circuit To A WG Carb

[Mastermind]

Hello all. I have questions. I have old husqy 3120 and old carb without H hole like in 1st post this thread. I can modified this carb and added H jet or need like 1st post?

Yes. Same process. You just have to accurately drill the pilot hole.

 

[huskihl]

Yes. Same process. You just have to accurately drill the pilot hole.

His is different….original

 

[huskihl]

Hello all. I have questions. I have old husqy 3120 and old carb without H hole like in 1st post this thread. I can modified this carb and added H jet or need like 1st post?

It can be done but I don’t recommend it with that particular carb. Yours is the early one with the threaded main nozzle

 

[Racer]

Yes. Same process. You just have to accurately drill the pilot hole.

It can be done but I don’t recommend it with that particular carb. Yours is the early one with the threaded main nozzle

Ok thanks guys. I drew a simple scheme, indicate my mistakes please

 

[huskihl]

Ok thanks guys. I drew a simple scheme, indicate my mistakes please
View attachment 405418

Your main jet is not the normal check valve /nozzle. If you run your new H jet fuel into the existing numbered jet, you aren’t really adding fuel

 

[huskihl]

Basically, you have a precision hole in the aux jet, say 1.2mm, from the fuel bowl down to the screen at the bottom of those threads. You can’t add an additional 1.2mm worth of fuel from your new H jet mid stream of the original 1.2mm jet and expect it to flow more fuel

 

[Racer]

Basically, you have a precision hole in the aux jet, say 1.2mm, from the fuel bowl down to the screen at the bottom of those threads. You can’t add an additional 1.2mm worth of fuel from your new H jet mid stream of the original 1.2mm jet and expect it to flow more fuel

It turns out that this carburetor does not make sense to modernize? Better take new wg-8 (or?) and make modding?

 

[huskihl]

It turns out that this carburetor does not make sense to modernize? Better take new wg-8 (or?) and make modding?

It’s not that you can’t do it, but I can’t explain well enough how to do it. I have done it once successfully but you’re taking a chance on ruining an early carburetor that isn’t made anymore.

I would recommend buying a new replacement carburetor and modifying that one. It will be straightforward with the info provided in the beginning of the thread

 

[Racer]

@huskihl thank you man+

 

[Mastermind]

It’s not that you can’t do it, but I can’t explain well enough how to do it. I have done it once successfully but you’re taking a chance on ruining an early carburetor that isn’t made anymore.

I would recommend buying a new replacement carburetor and modifying that one. It will be straightforward with the info provided in the beginning of the thread

Unless it's a primer bulb carb, it has the same nozzle. I think I can see a choke shaft.

 

[huskihl]

Unless it's a primer bulb carb, it has the same nozzle. I think I can see a choke shaft.

Not certain about the choke but it has the early screw in brass nozzle

 

[Mastermind]

Not certain about the choke but it has the early screw in brass nozzle

I hadn't even noticed that. I was looking at it as if it were the jet.

 

[legdelimber]

You guys mind if I mention that the screwdriver tip needs regrinding or replacing?
That slot in the jet is pretty roughed up from it.
Just a bit more twisting and the burr could be left dangling.
Wouldn't be much fun if it found its way into the metering lever area.