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1932 Buick Marval Carb replacement suggestions


JIM S

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Hi Guys, new to this site but I need some info/suggestions.  I know we are talking Points vs Pertronics, and I'm considering electronic here.  But a new topic.  The Dreaded Marvel Carburetor.  Had it rebuilt/restored on my '32 series 50.  Now, at a cost of $700.00, I've had enough of this carb; and I'm disgusted.  It  always runs so rich I cannot stay in the garage while the car is running.  All the plugs are completely black and so is the exhaust pipe;  black sooty exhaust just pours out the back and the engine misses and struggles to stay running at idle.  I want to replace it with a downdraft carb.  I've heard of this process but have some questions.  Exactly, what carb is a good replacement and where to find one.  Also, where/how to get an adapter from the carb base to the intake.   Few of us have a fabrication shop next door nor have the experience/knowledge to make one ourselves.  We all talk about this change and have seen it in pictures but I never get any specifics.  This always seems to be a secret and no-one shares the info.  I've seen the change on youtube and the conversion worked beautifully;  start up, idle, takeoff.  I love authenticity, no doubt, but I also love the car to be drivable.  When it comes to my Buicks, cost is not an issue. Please, any help would be appreciated.  

 

Regards, 

 

JIM

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Jim - I am one who has advocated such a change in the past, under certain conditions; HOWEVER, a few thoughts:

 

(1) I can feel your frustration in your post

(2) What kind of fuel pressure do you have at the carburetor?

(3) Have you done a compression check on the engine?

(4) Have you had your ignition system checked thoroughly?

(5) And finally (opinion) $700. is WAY TOO CHEAP for a professional restoration of an updraft zinc alloy Marvel. My first thought was talk to the restorer, until I read the $700. Probably no point in doing so.

 

But to answer the question you asked:

 

If you REALLY decide to do this, your Buick is a 230 CID engine. So a more modern carburetor from an engine of similar displacement. Think about fuel pressure, type of choke, availability of information, availability of parts; and finally, is your manifold one that CAN be turned over.

 

Finally, I doubt that there is anyone posting on this forum that truly loves the Marvels, but many do make them function. There is help here if you want it.

 

Think about it.

 

Jon.

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  • 5 months later...

Jim,

I was reading your post, and I wanted to respond to your post about your frustrations regarding the Marvel carb.

Not all Marvels are bad, maybe some age better than others and probably need to be replaced (pot metal is anything but precise and consistent car to car), but for what its worth many of us car owners still use the Marvel updraft carb with success, and there are MANY abused updraft tractors in the farm fields still working with updraft Marvels (yes, crazy).

I hope you found a good solution by now and are enjoying your car.

Hang in there, these cars need help evolving into the 21st century, and maybe beyond...

 

I have nothing to gain from a sales type pitch, but my Marvel carb has some internal parts near death, and I am working to rejuvenate (thanks to the help of many pros on this forum), and the carb is working well.  Take the spacer blocks in the attached pics for example, they look like they were in WWII, but the carb is still servicing my engine well despite the less than desirable spacer block status.

 

IMHO I have learned to be very meticulous with Marvel carbs - overcome warpage, monitor gaps, clean often, ensure no leaks, ensure float elevation, etc. 

They seem to be very needy to get setup, but then they just seem to settle in and run well without prolonged higher maintenance demands.

Maybe my experience is an anomaly, or maybe serendipitously my kids like the idea of a Marvel carb feeding the engine (too many Avengers movies).

Hopefully you have found some solace in good carburation on your journey, whatever intake solution you choose.

 

Best,

Mario

 

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Quote "there are MANY abused updraft tractors in the farm fields still working with updraft Marvels (yes, crazy)." End quote

 

Actually - no.

 

Marvel, like so many of the smaller carburetor companies, was acquired around 1930 or so by Borg-Warner. Another of Borg-Warner's acquisitions was Schebler.

 

The tractor carbs types DLTX, TCX, TRX, TSX (most common) and TTX were all Schebler designs. B/W closed the Schebler plant, and the designs were produced in the Marvel plant, and marked Marvel/Schebler. By 1933, Buick was Marvel's only remaining large customer (geography), although they did make a few carbs for both Graham and Nash. The Marvel plant was significantly more modern than the Schebler plant.

 

I have no record of any factory installation of a Marvel carburetor on any tractor.

 

Jon

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I did a lengthy post in my Me and My Buick thread regarding rich running with my 31 60 series car and it's Marvel carburetor and the solution to it on my car was lowering the fuel level in the float bowl.  If the fuel level is too high raw fuel spills over the top of the low speed nozzles rather than being drawn in under vacuum demand.   Any other source of leakage past float valve, gasket washers under lo/medium/high fuel nozzles needs to be ruled out as well.  On my car I found that the fuel level in the float bowl needed to be regulated to run 5/8" below the top of the bowl casting lip in order to keep the fuel level 1/16-1/6" below the low speed nozzles.  That would be a quick and dirty check, if fuel level in the bowl is running higher than that either the float level is too high or the float valve is leaking.  If the float valve is leaking and has a wear ridge it probably needs to be replaced.  If it is just dirty clean with lacquer thinner and polish with Happich Simichrome chrome polish which will not take metal off but will get the varnish off. 

 

If the carburetor float level is too high, DO NOT try to bend the brass float arm, IT WIIL BREAK.  Increase the thickness of the sealing washer under the float seat.    If you are still running a cork float and it is the culprit see my post about making a float from Balsa model airplane lumber.  Balsa has a slightly higher coefficient of buoyancy than pure cork.  It can be sealed with Sig model airplane hot fuel proof dope.  The siize of the base of the float can be adjusted to get proper float level by bonding thin layers of balsa to it to lower fuel level in the bowl, just be careful to not let it drag on the float bowl walls and don't make it any thicker than necessary to prevent fuel starvation at high speed running.   

 

Base plate of carburetor with bowl still attached to expose fuel nozzle array.  Shortest- lo speed, tallest- hi speed.

Carburetor 015.jpg

 

Top of low speed nozzle measured 9/16"  below top of bowl liip.  Each nozzle has a fiber washer gasket under it.  If ANY of them leak you have uncontrolled fuel leaking into the fuel air mixture resulting in rich idle.   

Carburetor 016.jpg

 

I scribed a line 5/8" below the bowl lip to set fuel level 1/16" below top of lo speed nozzle.  

Carburetor 017.jpg

 

A 95 yr old original float made of pure virgin cork.  You can't buy pure virgin cork any more, you get regrind cork that has been glued and it WILL NOT FLOAT.

Carburetor 001.jpg

 

But you can buy 1 inch thick balsa lumber from hobby stores that WILL float, is easy to cut and shape with a benchtop scroll saw and belt sander to make a dimensionally identical copy of the original float.  Sig is a standard brand of hot fuel proof clear model airplane dope that is a very effective sealer to prevent the balsa from becoming fuel logged.  I put the last coat on mine after it was assembled to make sure  it is totally sealed.  DO NOT bend the brass float arm.

Carburetor 007.jpg

 

Bottom of balsa float.

Carburetor 010.jpg

 

On the car running at idle for a float level check.

Carburetor 011.jpg

 

I found on first run the fuel level was still too high.  I added a 1/8" piece of balsa sheet, sanded to shape and re-sealed and that made a dramatic difference in idle mixture,  no more sooty tail pipe.  The other effective way to deal with float level is to add or remove thickness to the sealing washer under the float seat. 

Carburetor 019.jpg

Edited by Str8-8-Dave (see edit history)
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53 minutes ago, carbking said:

Quote "there are MANY abused updraft tractors in the farm fields still working with updraft Marvels (yes, crazy)." End quote

 

Actually - no.

 

Marvel, like so many of the smaller carburetor companies, was acquired around 1930 or so by Borg-Warner. Another of Borg-Warner's acquisitions was Schebler.

 

The tractor carbs types DLTX, TCX, TRX, TSX (most common) and TTX were all Schebler designs. B/W closed the Schebler plant, and the designs were produced in the Marvel plant, and marked Marvel/Schebler. By 1933, Buick was Marvel's only remaining large customer (geography), although they did make a few carbs for both Graham and Nash. The Marvel plant was significantly more modern than the Schebler plant.

 

I have no record of any factory installation of a Marvel carburetor on any tractor.

 

Jon

I stand corrected, thanks for the expertise and clarification Jon!

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2 hours ago, 1929wilbur said:

Hey CarbKing, what carb would you suggest be installed in place of the Marvel on a ‘23 Buick Touring.  It has the 23-45 6 cylinder engine.  Carter BB-1 ?  Any special adaptor needed?  

Carter did NOT suggest a BB-1 for the 23 Buick 6.

 

Stromberg suggested a type OE-2, with a 29/32 inch venturi; no adapter necessary.

 

Zenith did not suggest a replacement.

 

The Stromberg OE-2 is a brass carburetor with an economiser circuit (the "E" in OE-2), but it does have a zinc venturi; a new venturi would need to machined. Expensive to rebuild, but when finished (opinion) much superior to the Marvel.

 

I checked later Stromberg books for an SF series, but none was suggested, which probably means there was a clearance issue (the SF series is physically larger than the OE series).

 

Jon.

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