Carb help please HD-12b Vs HD-12-1

[CoreyB]

Hey guys quick question. I have a 372 that i am working on that needs a new carb. I can get a HD 12b from Husqvarna but through walbro I can get a HD-12-1 For almost half price. Is the hd-12-1 the same as the HD-12b
Any clarification would be awesome
@Poleman Do you know?

 

[Dub11]

Calling @mdavlee

 

[mdavlee]

I don't know the difference. The 12b is more common from what I remember seeing

 

[huskihl]

I don't know the difference. The 12b is more common from what I remember seeing

Me too

 

[Poleman]

View attachment 112430View attachment 112430 From what I know the 12-1 is for a lot smaller saw than the HD12b.
Is it an HDA 12-1 which is what I’m basing my reply off of.
Also an HD6-1 listed

 

[CoreyB]

It is more confusing (at least to me) that the 12b is not available through my walbro distributor . Just the 12-1

 

[CoreyB]

View attachment 112430 View attachment 112430 From what I know the 12-1 is for a lot smaller saw than the HD12b.
Is it an HDA 12-1 which is what I’m basing my reply off of.

That would explain why it is cheaper. Lol.

 

[Poleman]

That’s what I was thinking...

I doo have this in my drawer....off a 372 I put a Modded Zama on a while back....

 

[decableguy2000]

Go with the cheaper one, part number labels are expensive. When you search Walbro's site, by hd12 the only one that comes up is the HD 12-1

 

[NCFarmboy]

http://www.outdoorpartspower.com/pa...12-1/HD-12-1_PARTS_LIST/15HDHD121/15HDHD121~1
Shep

 

[Derf]

I believe that the 12-1 and 12b are essentially the same, the differences pertain to things like which side the throttle linkage and choke plate hook up to. For some reason I think Walbro made the carb in different configurations for different applications : Husqvarna’s 372xp saw has the throttle on the left and the choke on the right. But I believe when they had their 2-series, like a 262, the choke was on the left and the throttle was on the right. So the B designation may indicate which way the throttle / choke shafts are set up. Maybe also small other differences like fuel inlet pipe orientation, but I’m less certain about that.
Perhaps you can swap things around from the 12-1 to the 12b.

But all of this is just hearsay, IMHO, $ 0.00002, etc.

 

[Derf]

View attachment 112432 View attachment 112431 View attachment 112430View attachment 112430 From what I know the 12-1 is for a lot smaller saw than the HD12b.
Is it an HDA 12-1 which is what I’m basing my reply off of.
Also an HD6-1 listed

The HD6 was the pre-EPA carb used on the 372xp before they switched to the HD12B when the EPA mandates hit. I feel like the 12B has a slightly smaller Venturi, but I don’t have numbers in front of me.
@SawTroll.

HD12B carbs are cheap and plentiful on the bay.
I think I have 2 spares, and I’m sure @Mattyo has some too.
They don’t really go bad either. No accelerator pump to fail or crazy impulse setup like on the HDA199. They generally only need a new carb kit to run. Although I have heard from some people that they are hard to tune or finicky compared to the Zama option, but I never felt that way about mine.

 

[huskyboy]

The HD6 was the pre-EPA carb used on the 372xp before they switched to the HD12B when the EPA mandates hit. I feel like the 12B has a slightly smaller Venturi, but I don’t have numbers in front of me.
@SawTroll.

HD12B carbs are cheap and plentiful on the bay.
I think I have 2 spares, and I’m sure @Mattyo has some too.
They don’t really go bad either. No accelerator pump to fail or crazy impulse setup like on the HDA199. They generally only need a new carb kit to run. Although I have heard from some people that they are hard to tune or finicky compared to the Zama option, but I never felt that way about mine.

The hd6 has a little smaller Venturi than the 12 I believe if I’m not mistaken.

 

[NCFarmboy]

6 is smaller. Walbro lookup does not use the a/b suffix its always -1 as in hd-12-1, hd-6-1.
Shep

 

[CoreyB]

6 is smaller. Walbro lookup does not use the a/b suffix its always -1 as in hd-12-1, hd-6-1.
Shep

So the 12-1 is the same as the 12b?

 

[decableguy2000]

90% sure its the same.

 

[NCFarmboy]

I t is the same! 100%.
Shep

 

[SawTroll]

I don't know the difference. The 12b is more common from what I remember seeing

As I understand it, the difference is about Walbro and Husky using different designations for the same thing - but I can't confirm that 12b (always) is exactly the same as 12-1.

I suspect that it hardly matters though?

 

[SawTroll]

The HD6 was the pre-EPA carb used on the 372xp before they switched to the HD12B when the EPA mandates hit. I feel like the 12B has a slightly smaller Venturi, but I don’t have numbers in front of me.
@SawTroll.

...... .

If the specs that Walbro used to list were to be trusted, it actually was the other way around - the HD 6 had a 16.67mm venturi (same as the HDA 199 and HDA 87 btw.), while the HD 12 has a 17.46mm one.
This beats me regarding logics, but nobody has claimed that the Walbro specs are faulty in all the years I have been on forums like this - I still have my doubts though.

Another difference is that the HD 6 doesn't have adjustment limiters, while the HD 12 has (EPA related). My logic tells me that this should have been the only difference, but apparently not?