Zenith Carb Question(s)

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Ken Tuvman
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Zenith Carb Question(s)

#1 Post by Ken Tuvman » Sun Aug 18, 2019 9:27 am

Hi Everyone,

I've decided to go with my Zenith 32NDIX for my '61 T5 356 Super Project (it also came with Weber 40IDFs) and am looking for some answers and a good illustrated book to serve as a guide while reinstalling parts - I plan to do one at a time - there's one thing that's throwing me off - one of the accelerator pump chambers has an Allen screw with a hex nut and the other one does not. I know the Webers are supposed to be easier to tune but I'd like my engine to be more authentic and I've got the Knenct air cans to go with the Zeniths.

I've looked at some of the exploded views of the carb and I'm not seeing it. Also, one of the carbs needs (2) new flathead screws for the round plate - plan to check parts bin at my son's auto shop as they do have a pretty big selection of metric nuts & bolts.

I'd like to find this book and sent a note to the author but wondering if I can't find it what other books provide good info. on the 32NDIX.

Below are my pictures and also, are these little washers (#73) that go over the bolt readily available? I read the metal washers are more reliable than the fibre washers.

Also, we may be wind up with a 1720cc engine - in this event, is it suggested to change any of the jets to adapt to the increase in HP?

Also have heard good things about Duane Spencer book - does it have detailed info on overhauling the Zeniths?

Thanks for your help!

Ken in MN
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Tom Keating
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Re: Zenith Carb Question(s)

#2 Post by Tom Keating » Sun Aug 18, 2019 10:37 am

That Zenith carb book is no longer available. Charlie White passed away a few years ago.
Tom Keating
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Ron LaDow
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Re: Zenith Carb Question(s)

#3 Post by Ron LaDow » Sun Aug 18, 2019 11:20 am

Charlie wrote that book on the basis of one set of Zeniths he rebuilt. All I'll say is that he did some wonderful work for all of us, and that is not one of his best efforts.
That hardware on your left-hand carb is someone's fix or hot-rod effort. There are decent used carb tops around, I'd go looking for one.
Pretty sure you'll find a consensus that Zeniths are far easier to tune for 161 engines than any of the other options, and C jetting works just fine on 1720cc engines with street compression ratios.
#73 is a sealing washer; Cu or Al.
I don't recall if Duane covered Zeniths.
I've written stuff on these carbs over the years; it's in the archives.
Ron LaDow
www.precisionmatters.biz

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Ken Tuvman
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Re: Zenith Carb Question(s)

#4 Post by Ken Tuvman » Sun Aug 18, 2019 12:03 pm

Thanks Tom and Ron!

Ron - thanks for the heads up on that piece that doesn't show up in the fiche!

So this piece of "Hardware" so a modification - that makes sense - wonder what it did?????
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I was told by PO that the car was raced at some point.

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Ken Tuvman
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Re: Zenith Carb Question(s)

#5 Post by Ken Tuvman » Sun Aug 18, 2019 1:05 pm

Okay - think I figured it out - the allen head and bolt was some sort of repair - when I was disassembling saw some crumbling that must've been old epoxy or JB weld - I'll heed Ron's suggestion and find a replacement top - thanks again!

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Tom Wavrin
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Zenith Carb Question(s)

#6 Post by Tom Wavrin » Thu Aug 22, 2019 1:42 am

Ken, I have Charlie White's Zenith book and have compiled a short list of additional comments for myself that relate to the carb's rebuild. You can borrow it if you would like. Be aware that carb tops that are offered for sale may have stripped threads for the fuel line bolt. 356 Carb Rescue repaired one of mine.
Ron LaDow sells a velocity stack, of which I'm a satisfied user. that offers the carb top protection from worsened grooving by the air filter.
Tom, Reg # 10576, Oregon
'62 1600S Karmann HT, Heron/Green

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Ken Tuvman
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Re: Zenith Carb Question(s)

#7 Post by Ken Tuvman » Fri Aug 23, 2019 10:10 am

Thanks Tom - sending you an email . . .

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Wes Bender
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Re: Zenith Carb Question(s)

#8 Post by Wes Bender » Fri Aug 23, 2019 2:18 pm

I don't think Charlie's book was meant to be the Bible on Zenith rebuilds. More of a beginner's guide for folks who had never messed about with them. If you want to have Zeniths that work the way they should without having to totally immerse yourself in the rebuilding process, send them to 356 Carburetor Rescue.
Some days it just isn’t worth the hassle of chewing through the restraints......

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Ken Tuvman
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Re: Zenith Carb Question(s)

#9 Post by Ken Tuvman » Fri Aug 23, 2019 3:47 pm

Thanks Wes,

I've restored several old air cooled BMW Boxer Airheads & overhauled carbs but never a Zenith - I've already cleaned them one at a time and they're not too complicated but having a book is always a good cross check - like a checklist.

Am surrounded by professional mechanics if I run into any issues and actually I enjoy figuring things out. I'm familiar with 356 Carb Rescue and have ordered kits from Candace. I think its cool that they actually hook up the carbs they overhaul to a bench 356 motor and dial them in - I figure if I really screw things up I can always send them over to them but why not try first?

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Wes Bender
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Re: Zenith Carb Question(s)

#10 Post by Wes Bender » Fri Aug 23, 2019 4:28 pm

I've rebuilt mine too. With a little care you can do it. Go for it.
Some days it just isn’t worth the hassle of chewing through the restraints......

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Craig Richter
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Re: Zenith Carb Question(s)

#11 Post by Craig Richter » Fri Aug 23, 2019 6:52 pm

Just to stir the pot a little, your 1720cc will run stronger with Webers. :D :wink:
 

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C J Murray
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Re: Zenith Carb Question(s)

#12 Post by C J Murray » Fri Aug 23, 2019 7:37 pm

Craig Richter wrote:
Fri Aug 23, 2019 6:52 pm
Just to stir the pot a little, your 1720cc will run stronger with Webers. :D :wink:
You just had to go there! Now heads are exploding and people are popping valium. :shock:
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Ken Tuvman
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Re: Zenith Carb Question(s)

#13 Post by Ken Tuvman » Fri Aug 23, 2019 7:46 pm

CJ - thought about both carb brands and in the interest of form and function (and I know my motor will now be a 1720) decided to honor the original design - according to Leonard, the Neutek cam is built/designed for the Zeniths.

Trust me guys, you're not going to see me on the race track!

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Ken Tuvman
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Re: Zenith Carb Question(s)

#14 Post by Ken Tuvman » Fri Aug 23, 2019 7:49 pm

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Ron LaDow
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Re: Zenith Carb Question(s)

#15 Post by Ron LaDow » Fri Aug 23, 2019 11:38 pm

You are welcome to try fiddling with Webers; who am I to deny someone a life-long endeavor?
Ron LaDow
www.precisionmatters.biz

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