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-   -   Zineth air balanced carb compensator jet (https://www.fordbarn.com/forum/showthread.php?t=128660)

Chip A 01-14-2014 11:02 AM

Zineth air balanced carb compensator jet
 

Good morning folks,

I'm in the process of overhauling my three year old Zenith Air Balanced carb. (Purchased from MAC's three years ago).. In the disassemble process, I was very careful to place everything on a felt mat so they would go back exactly where they came from. Nice plan, but the plastic basin the mat was in got hit and knocked on the floor......:mad: For anyone who has overhauled the air balanced Zenith, there are two jets that are physically the same size...I believe they are both 10-32 X apx 1/4 inch.

My question is this: Which jet is the compensator jet that is installed in the bottom of the float bowl?? The smaller orifice or the one with the larger orifice????? Thanks
Chip A

H. L. Chauvin 01-14-2014 01:32 PM

Re: Zineth air balanced carb compensator jet
 

Hi Chip,

Hate to see 0 responses; but honestly I have no direct technical answer.

In trying to assist if nobody responds, just try it one way, then the other way.

Then go with the way it works best.

Over 99% of suggested solutions I learned in life that worked, came from my fearless father & others who never finished school.

Gary WA 01-14-2014 01:32 PM

Re: Zineth air balanced carb compensator jet
 

2 Attachment(s)
here you go. left picture one with #19 is comp jet the other is needle seat-#38 on it. they are 5mm 75pitch tap french made as per Henry.

Chip A 01-14-2014 02:13 PM

Re: Zineth air balanced carb compensator jet
 

Thanks Guys,

So, if I read the attachment correctly, the comp jet is the larger of the two orifice wise....i.e. greater flow and it is also the longer of the two...
After I had posted the questions, I found (By accident) a page that showed some info that goes along with what you guys posted. It looks like the comp jet is a #63 .037 with a 138-142 cc/min flow rate. The Idle jet (Air balanced Zenith 2) should be a #75 .021 with a 38-42 cc/min flow rate.

If anyone comes up with anything else, please let me know. I going to hold off on reassemble until tomorrow. It's January in Connecticut, so there's NO rush.....LOL Thanks again:)

Gary WA 01-14-2014 02:21 PM

Re: Zineth air balanced carb compensator jet
 

Quote:

Originally Posted by Chip A (Post 803509)
Thanks Guys,

So, if I read the attachment correctly, the comp jet is the larger of the two orifice wise....i.e. greater flow and it is also the longer of the two...
After I had posted the questions, I found (By accident) a page that showed some info that goes along with what you guys posted. It looks like the comp jet is a #63 .037 with a 138-142 cc/min flow rate. The Idle jet (Air balanced Zenith 2) should be a #75 .021 with a 38-42 cc/min flow rate.

If anyone comes up with anything else, please let me know. I going to hold off on reassemble until tomorrow. It's January in Connecticut, so there's NO rush.....LOL Thanks again:)

other way around! short is comp jet with the #19 on the top.

Chip A 01-14-2014 02:30 PM

Re: Zineth air balanced carb compensator jet
 

Thanks Gary..Good catch !

dave in australia 01-14-2014 02:54 PM

Re: Zineth air balanced carb compensator jet
 

Quote:

Originally Posted by Gary WA (Post 803486)
here you go. left picture one with #19 is comp jet the other is needle seat-#38 on it. they are 17mm 75pitch tap french made as per Henry.

I don't think they're 17 mm. That's nearly 3/4" and a 75 pitch is one thread per 3". Maybe .75 pitch which would be close to 32 TPI. Also if you meant 1.7 mm, then that would be close to 1/16". 1/4" is close to 6mm. So maybe they're a 6mm x .75 pitch in metric.

Purdy Swoft 01-14-2014 03:21 PM

Re: Zineth air balanced carb compensator jet
 

The other Zenith part that resembles the compensator jet is the adjusting needle seat and was used until jan.1930 , after that it waspart of the casting and not removable. The hole in the adjusting needle seat has a tapered seat in the screw driver slot. The compensator jet doesn't have the tapered seat in the hole. The parts look very similiar. The needle seat goes under the needle of the GAV. If the parts get mixed up, it will still run but not exactly right.

Benson 01-14-2014 03:58 PM

Re: Zineth air balanced carb compensator jet
 

About limited responses to this post ... the text says new carb and air balanced carb so I for one assumed it was about the new Zenith Forklift carb about which I know nothing.

5mm .75 is the jet thread size.

Gary WA 01-14-2014 04:30 PM

Re: Zineth air balanced carb compensator jet
 

Quote:

Originally Posted by dave in australia (Post 803536)
I don't think they're 17 mm. That's nearly 3/4" and a 75 pitch is one thread per 3". Maybe .75 pitch which would be close to 32 TPI. Also if you meant 1.7 mm, then that would be close to 1/16". 1/4" is close to 6mm. So maybe they're a 6mm x .75 pitch in metric.

my mistake not thinking 5mm 75 pitch:)

Chip A 01-14-2014 08:11 PM

Re: Zineth air balanced carb compensator jet
 

Sorry if I caused heartburn guys.... It is a "New" Zenith "air balanced" carb.. Sold by MAC's and Sniders for $450.00.. Due to problems that were not their fault, it needed to be overhauled and try as I did to keep the parts in the exact order they came out, the tray was knocked over. Thanks to all for the input.

Chip

Gary WA 01-14-2014 09:02 PM

Re: Zineth air balanced carb compensator jet
 

Quote:

Originally Posted by Chip A (Post 803700)
Sorry if I caused heartburn guys.... It is a "New" Zenith "air balanced" carb.. Sold by MAC's and Sniders for $450.00.. Due to problems that were not their fault, it needed to be overhauled and try as I did to keep the parts in the exact order they came out, the tray was knocked over. Thanks to all for the input.

Chip

Thanks for clarifying. my mistake to.:rolleyes:

Chip A 01-15-2014 08:27 AM

Re: Zineth air balanced carb compensator jet
 

Well, they say confession is good for the soul...LOL so, here is my confession for the day. What I was looking at as the "Idle Jet" was actually the older style Zenith mixture seat.. The "New" style has that already machined into the body. The idle jet is a long tube style. When I went to match up old parts to new parts, there was no OLDER other short style jet. Only the Comp jet... Engage brain long before asking for help....LOL.LOL.LOL Thanks again guys.

Purdy Swoft 01-15-2014 12:03 PM

Re: Zineth air balanced carb compensator jet
 

I think that I explained it in post number eight, yesterday.

Chip A 01-15-2014 02:48 PM

Re: Zineth air balanced carb compensator jet
 

Purdy....you did a yoman's job of explaining it too... It was me.. I was looking at the wrong jet and thinking it was the idle jet....My bad..not yours.


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