Rod L

Grimy, Finally someone with some actual help, thank you so much, it is much appreciated. No the stumbling, miss and backfire that is occurring with the Carter down draft, did not occur with the Marvel. The Marvel equipped engine just had very low power and as I mentioned in another post, the model A's I have are much more peppy. I hope to get it out this weekend to see if my changing the intake manifold gaskets made a difference. Again thanks for the help and for staying on topic.

And still no Marvel carburetor re-builder recommendation.

I guess I just don't understand a statement like that. When you have no idea as to how the car was running at the time that I decided to go down draft. If there was a carburetor shop capable of rebuilding my existing Marvel then why wasn't it recommended? Being it wasn't, that left me with two choices: park the car or go down draft. Now that I have gone down draft, I am accused of not listening to the offered advice and if you look closely you will note that STILL no where has anyone pointed to a capable Marvel carb re-builder. I have completed what appears to have been a successful conversion (so far). The engine (with the Carter w1) starts, idles and accelerates just fine (with no load). It does not like accelerating under load, and that is the issue. I am certain it is something to ,do with the carburetor, i just don't know what! I guess maybe I need to go to a Carter forum to find my answer. Sorry to have troubled the "experts". Rod

Ed, Wow, aren't we spicy this morning! If you were to have read all the posts in this thread you would be aware that in my 2nd post I asked for a recommendation for a re builder of the marvel should I decide to go that route, you would then be aware that NO such recommendations arrived! I then proceeded down the down draft trail. I also did follow Carbking's advice and used the Carter w1 carburetor (the one I am seeking assistance with. Also being 78 years old and while not an expert on these cars, I have modest mechanical abilities and have been at this awhile.. As for all this help I'm being offered, could you point me too it? Only "Oldtech" has answered my question.

As to the last two responses, Edinmass & dibarlo, I didn't ask for a critique! Neither of you gentlemen have driven the vehicle in question and have no idea as to the nature of its power, I am not trying to hot rod or even make a "1958" out of it. I have retained the complete Marvel system for the next owner should they chose to use it. The poster prior to my last post, suggested a possible adjustment to the carb I am using, I was merely seeking clarification for his suggestion and NOT someone else's opinion as to the merits of what I decided to do. If you don't have a directly related answer to the question asked, you are just making noise. Rod

OK, suppose I take care of the vacuum leaks (gaskets are on the way) and that doesn't fix the problem, how do I go about checking/adjusting the "Metering rod"? Is there a book or other description of the procedure? Rod

Well Dave, as i mentioned in the above post, it started right up and the idle is near perfect plus it revs up (while stationary) very nicely. However, I got it out of the garage for a test drive and it was anything but perfect. Missing, no power and the occasional exhaust backfire. I found that closing the choke to about a 1/4 opening results in some improvement so I'm thinking i have a vacuum leak causing a lean condition. When I reversed the manifold, the gasket looked good so I didn't replace it (mistake?) I sprayed starter fluid around it and thought I detected an rpm increase (if so, it was very small). I only see one external adjustment on this Carter W1 carb and I think that is for idle? The carb is rebuilt and supposedly test run on an engine and adjusted? Guess I'll start over! Rod

Got it installed and it runs. Using a re-manufactured 1941-1948 Chevrolet Carter W1 Carburetor on top of a reversed existing intake manifold and a fabricated throttle support made from 3/8" solid aluminum, a Bell crank, brass all thread rod and Mr. Gasket 3811G Carb Link Ball Joint Quick Release fittings, the whole thing came together in about 3 hours. The hardest part was cutting the aluminum support plate (I needed extra space to get behind it to get the nuts on it). I haven't had a chance to drive it yet, but it started right up, idles super smooth and rev's up as expected. I still have to get a choke cable for it, but starts up easily without it (inside heated garage though). The bell crank needed to have the holes enlarged to accommodate the linkage fittings but works fine now. With the bell crank and the threaded rod and fittings there are endless adjustments to the linkage. I did not use an adapter so the carb sits on a 45* angle from the manifold, it did not pose a problem as the linkage i'm using is very much adjustable and swivels nicely, also, with that 45* turn it swings the fuel intake further from the exhaust manifold reducing the likely hood of a fuel leak causing problems (I'm still going to put a deflector in that location). I am very pleased so far. Here's a breakdown on costs as of this date: bell crank...$ 34.54 threaded rod and quick release fittings $ 36.44 aluminum plate $ 19.48 carburetor $ 395.00 Choke cable 20.95 Total: $506.11 Here's some photos: (more to come later). Rod

Is there supposed to be a gasket between the blanking plate and the heat riser? There wasn't one when I removed the heat riser. I suppose a little high temp exhaust silicone would suffice? I now have the 3/8th aluminum plate, "bell crank" and an assortment of bolts to start fabricating the throttle linkage support. The carburetor is arriving tomorrow, so I expect to have the engine back up and running by Monday if the creek don't rise and the wife doesn't have too many honey-do's.

Dave, yes that is along the same lines. I just ordered a 3/8" x 8" x 10" piece of solid aluminum which should do the trick. I've already reversed the Manifold (very easy and straight forward). It looks like the horn can use the same mounting holes in the manifold but with thinner and longer thru bolts and I may have to reverse the bracket on the horn to mount the carb (still waiting for the carb to arrive). Rod

After studying Daves photos of the blanking plate and the bracket attached to it, I think it might be possible to just fabricate a longer blanking plate with a "bell crank" in place of the angle bracket. Dave, thanks again for the photos they certainly are a huge aid in figuring out how to set his up. i've got a 1941-1948 Chevrolet Carter W1 Carburetor on order and will probably make up an adapter to swing it 45 degrees, though leaving it is also a possibility. I never would have thought to use the blanking plate for support of a bell crank without those photos!!!!😀 Rod

OK, guys, a bit of a confession here. I had already bought the car but not yet received it (it's on the transport as we speak). I am probably more interested in what to look out for when it arrives and what maintenance items to perform. Here's what I know so far. It came out of a Museum around 1984 and went into a private collection supposedly after a restoration? I recently was taken on consignment and had the carb rebuilt as well as the ignition system. It was started and I have videos of it both driving and stationary. i guess I.m looking for any ideas on what to do to further ensure its roadability? VIDEOS: https://youtu.be/OkmayyyjUYQ https://youtu.be/zBUoJUZgSAY My aplogies Rod

What are the pros and cons of buying a car from a museum? What would you recommend as steps to take should one be purchased? If you know of a thread with these questions having already been asked, please point me in that direction. Rod

Jon, Nothing is set in concrete, and until I actually make the purchase, I am open to any and all recommendations. Rod

Great information in this thread, thanks to all who have contributed so far. if an adapter was fabricated to turn the carburetor 45 degrees so that the linkage would be better accommodated, the carburetors i looked at all have the fuel inlet on the back side. To reduce the danger of fire from fuel leakage you could use a deflector to route any dripping fuel away from the manifold and down pipe, i think i would also sandwich some insulation wrap between the deflector and the manifold. I have checked the exhaust "down pipe" and it is not in the path of any possible dripping fuel. Based on what I have garnered from this thread, I am going to proceed with mounting a downdraft carb on the car. I will keep a detailed record both written and pictorial and then post it. I intend to use this carb https://newcarburetors.com/?product=y200-universal-carburetor and a gasket from Olsons gaskets if the model A's don't work, I have a bunch of those lying around here to try. (thanks for the tips Hugh and Kevin). I'm sure I will run into issues and will need the expertise of this group to guide me. Thanks, Rod

kevin Thanks for the response and photo, It's just what I was looking for. The car has an electric fuel pump with pressure regulator set to 1 psi and works great with the Marvel. I suspect that I will have the same 45 degree problem and will have to work out a solution for the throttle (Lokar with return spring?). Where did you get your intake manifold gasket? I looked on 'Bobs" but nothing on there web site. Would you have a photo showing the exhaust blanking plate? Thanks again Rod

Would this be a good carb to use? https://newcarburetors.com/?product=y200-universal-carburetor or jon at carbking what have you got? Rod

ok guys let me see if I have this conversion to a down draft carburetor correct (please see photo for reference). I remove the two bolts as indicated by the two upper red lines, as well as whatever is holding on the exhaust heat mechanism? This should remove everything below the short red line. Now remove the intake manifold, reverse it and with a new gasket, re-install it. Install an appropriate carb (Would this work?). Figure out throttle and choke linkage. Start the car🤣 Rod

Mark, Yes, that is what I plan on doing this winter. I am just looking to see if anyone can point me in the direction of a writeup by someone who has done this. I can probably forge ahead on my own as it seems pretty straight forward. Is an adapter needed? How is the throttle linkage managed? An automatic choke would solve the choke cable issue but that's probably not a problem anyway. Which model# carb is generally used? See, lots of questions. One more: If I decided to have the Marvel rebuilt, Who is recommended? Rod

I am seriously considering converting to a down draft carb. (I will be retaining all the stock parts to convert it back). I figure I will need a replacement gasket for when I remove and reverse the manifold. What is the recommended carb to go with? The engine is the "standard six". i'm thinking of using a "choke cable" with a return spring for the throttle. What other parts and bits might you guys who have done this recommend. I am open to all ideas. To counter all the naysayers who are sure to pop up, I'm doing this because I don't like the power i'm getting or should I say lack of power. I've got 3 Model A's that even the weakest of which will out accelerate this buick at any time. Not at all what I was expecting. Rod

I am in love!!! Rod

Lots of thumbs up on that critter! 😁👍👍 Rod

update, my mistake, what appeared to be a crack in that adapter was actually just dried paint!

Well, Surprise surprise!! I removed the canister and low and behold thee was a spin on filter under it (pic 1)! The canister was 1/2 full of oil (pic 2) and the filter was hand tight. So why is the canister filling up and overflowing? I removed the canister adapter (pic 3) on careful examination there appears to be a split (Pic 4) in the adapter side, or is that just a casting imperfection and not related to the oil spill? Any comments? I'm guessing that being I'm not the owner who bought the adapter (not even sure who's product it is?); I'm going to be buying another one. I suppose I could just install a new filter and start the car without the canister to see if i get an oil bath?