Zenith Carburetor Questions

[CleaningTheGarage]

I decided to bench the Tilotson from my earlier thread and buy a rebuilt Zenith.

The top casting is marked w/ a Z on the outboard side and 27 G on the engine side. The bottom casting is marked Zenith 1.

Popped it in and gas is leaking steadily from the vent hole on the engine side. With help from posts here and YouTube I thought I had it narrowed down to a float issue.

Upon opening I found several issues and have several questions.

1. The Float - I tested the float, no holes. The pivot arms on the float extend beyond the pivot mounts that attached to the casting. When mating with the bottom, they catch on the lip of the bowl. I think once seated (with a gasket not shown in the picture) they might still be rubbing/catching so the float stays down with the valve in the open position. Can I just file the brass at the back to create clearance?

2. The Idle Jet - looks like it was gooped with something so it would seat and seal properly. That goop has cracked and the tube part of the jet spins freely and isn't completely straight. Is the spinning and/or crookedness normal? Should I re-goop and move on or replace? The seat it fits into (Main Jet?) looks questionable to my eyes too.

3. The Venturi - Had a dent on the lip. When I tried to straighten it, it cracked. Unitl I get a replacement, can I just break the rest of the cracked part off, or will it impact its performance?

Thank you in advance for your input.

[Y-Blockhead]

Where did you get this so called "rebuilt Zenith"?

I think I would be asking these quetions to the "rebuilder" before Ford Barn. This carburator seems to have a lot of issues. What is with all the corrosion?

Makes ya wonder what else is wrong.

[Gary WA]

Originally Posted by CleaningTheGarage

I decided to bench the Tilotson from my earlier thread and buy a rebuilt Zenith.

The top casting is marked w/ a Z on the outboard side and 27 G on the engine side. The bottom casting is marked Zenith 1.

Popped it in and gas is leaking steadily from the vent hole on the engine side. With help from posts here and YouTube I thought I had it narrowed down to a float issue.

Upon opening I found several issues and have several questions.

1. The Float - I tested the float, no holes. The pivot arms on the float extend beyond the pivot mounts that attached to the casting. When mating with the bottom, they catch on the lip of the bowl. I think once seated (with a gasket not shown in the picture) they might still be rubbing/catching so the float stays down with the valve in the open position. Can I just file the brass at the back to create clearance?

2. The Idle Jet - looks like it was gooped with something so it would seat and seal properly. That goop has cracked and the tube part of the jet spins freely and isn't completely straight. Is the spinning and/or crookedness normal? Should I re-goop and move on or replace? The seat it fits into (Main Jet?) looks questionable to my eyes too.

3. The Venturi - Had a dent on the lip. When I tried to straighten it, it cracked. Unitl I get a replacement, can I just break the rest of the cracked part off, or will it impact its performance?

Thank you in advance for your input.

Looks like a lot wrong with it, jets idle jet corrosion etc. where are you located? I'd get with the seller and question the condition of carb!!!

[CleaningTheGarage]

I will be contacting the rebuilder, but best case there will be a return and a refund or a price concession and a core I'll need to rebuild. Was hoping to go into that discussion with as much knowledge and detail as possible.

Thought that's what this forum was for....

I won't reveal where I got this at this point as I'm not one to trash someone publicly without facts and giving them an opportunity to provide an explanation.

Thanks for the input.

[Gary WA]

Originally Posted by CleaningTheGarage

I will be contacting the rebuilder, but best case there will be a return and a refund or a price concession and a core I'll need to rebuild. Was hoping to go into that discussion with as much knowledge and detail as possible.

Thought that's what this forum was for....

I won't reveal where I got this at this point as I'm not one to trash someone publicly without facts and giving them an opportunity to provide an explanation.

Thanks for the input.

Keep us posted on your resolve! And whats your location?

[47topless]

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Originally Posted by CleaningTheGarage

I will be contacting the rebuilder, but best case there will be a return and a refund or a price concession and a core I'll need to rebuild. Was hoping to go into that discussion with as much knowledge and detail as possible.

Thought that's what this forum was for....

I won't reveal where I got this at this point as I'm not one to trash someone publicly without facts and giving them an opportunity to provide an explanation.

Thanks for the input.

You may need to wait, longer than an hour, for an "acceptable" reply.

[johnbuckley]

1. The Float - The float looks normal to me, It is unlikely to rub on the lower casting when assembled but get the so-called "rebuilder" to check it .
2. The Idle Jet is useless and needs replacing.
3. The Venturi - That small chip on it is unlikely to impinge on performance of a stock A
but the "rebuilder" should have replaced it nevertheless.
I concur with everyone else - send it back it has not been rebuilt correctly

[CleaningTheGarage]

Thanks All!

Can someone recommend a source of quality rebuilt carbs?
Or is my dream of anything other than one I rebuild myself just that; a dream?

There is a charity car show at my church this weekend that I would like to drive to, rather than having to trailer it for two miles.

I'm in Southern Indiana and have joined both the Columbus, IN and Falls City (Louisville, KY) clubs.

Zenith was purchased on eBay from a seller with over 4K transactions and 100% positive feedback. Thought I was safe. Waiting for his/her response.

[Jim/GA]

Originally Posted by CleaningTheGarage

Thanks All!

Can someone recommend a source of quality rebuilt carbs?
Or is my dream of anything other than one I rebuild myself just that; a dream?

Talk to the guys at Bert's. Their website says you have to supply a core and they are 10-12 weeks out, so not a quick solution. But I am very confident that in the end, you will receive a well rebuilt carb.

https://modelastore.com/

[Gary WA]

Originally Posted by CleaningTheGarage

Thanks All!

Can someone recommend a source of quality rebuilt carbs?
Or is my dream of anything other than one I rebuild myself just that; a dream?

There is a charity car show at my church this weekend that I would like to drive to, rather than having to trailer it for two miles.

I'm in Southern Indiana and have joined both the Columbus, IN and Falls City (Louisville, KY) clubs.

Zenith was purchased on eBay from a seller with over 4K transactions and 100% positive feedback. Thought I was safe. Waiting for his/her response.

One of the club members would be glad to loan you a carb!!!

[CleaningTheGarage]

Update! Seller agreed to a return and refund, for which I'm grateful.

That left me with four Tillotsons. The one that came on the car, the rebuilt one I purchased "rebuilt" and two of unknown condition I picked up at an auction in Indy a couple of weeks ago. Bought a rebuild kit and worked through the one that came off the car originally and checked/set float levels on those two.

Swapping between the two "rebuilt" ones, car runs, but rough. With a cleaned out tank, new pencil filter, new filter in the sediment bowl and fresh gas (with a bit of MMO), I'm confident the fuel system is good, so now think it might be electrical. Ammeter shows full discharge when car is running and there is a drain on the battery when it sits overnight w/o a trickle charger on it.

I have the Green Book and am off to the barn to run through the troubleshooting process. Thank you all for your advice and support.

Jim: I'll probably go the Bert's route, but need to find a core. Now I have an excuse, I mean reason, to go to the swap meet in Burlington, KY in two weeks and Hershey next month.

P.S. At the Club meeting last night we discussed having mini-seminars for newbies like me. A bring your car, get your hands dirty and learn how from an experienced member. Interestingly, a number of members who aren't new by any standard, but usually leave maintenance to someone else were interested. Another good way to transfer knowledge and keep the hobby alive!

[CT Jack]

It appears the so called rebuilder doesn't know much about rebuilding carburetors. Don't waste you time trying to make it work. Send it back and get your money back if you can. I would go with one of the reputable parts vendors as they will make good if there is a problem.

[Benson]

About cores:

[Fullraceflathead]

FYI you'll find the tillotson carburetor is actually a much better performing carburetor it's better by design and also more efficient than the zenith!!!

[David in San Antonio]

I don’t suppose anyone will jump to their feet, shout “Eureka”, and switch from Zenith to Tillotson just for this, but One other benefit I’ve come to appreciate is how light weight the Tillotson is. On the occasions when removal and reinstalling is needed it’s so much easier to hold in one hand while bolting it in place compared to the cast iron Zenith. The sidemount spare tire makes it an awkward reach so this makes a big difference. I’m happy to report The Wretched Roadster doesn’t run hot even when the weather is well over 100*F, so the oft-reported warnings about pot metal warpage has not proved to be a factor.

[nkaminar]

Here is a completely different direction. I am very happy with my down draft Weber carburetor. It is available with the intake manifold and throttle linkage in a kit form. The two barrels work sequentially. The 32 mm side is used for most of the driving but when the pedal is on the metal the 36 mm side opens up. I get good fuel economy and extra power when I need it. Different size main and idle jets are available to tune the carburetor to your needs. The Weber is reliable.

[CleaningTheGarage]

Uh oh. Didn't mean to spark the great carburetor brand debate.

Probably time to change the subject. What kind of oil should I use?

Over time, I'll probably end up with both (or all three) and see which works best for me.

Benson: Your comments on cores disappeared, but are all good things I'll look for in a core.

[Gene F]

Originally Posted by nkaminar

Here is a completely different direction. I am very happy with my down draft Weber carburetor. It is available with the intake manifold and throttle linkage in a kit form. The two barrels work sequentially. The 32 mm side is used for most of the driving but when the pedal is on the metal the 36 mm side opens up. I get good fuel economy and extra power when I need it. Different size main and idle jets are available to tune the carburetor to your needs. The Weber is reliable.

I never knew that. Where did you get that? I have the big valves, H/C head, and IB-330 cam, plus all the other stuff. I might like to try this.

How do you get fuel to it?

[700rpm]

I bought a perfect rebuild from TheModelAGuy on the MAFCA Classifieds site. Highly recommend. Lots of units in stock, reasonable prices, nice guy.