EssexSuper Six Fuel Problem

Unknown

Recently acquired a Super Six (1929) with a Stewart Vacuum fuel system. Basically do not understand how it works. Car starts but falters on throttle indicating a fuel problem. Can anyone help as to how the Stewart works to help trace fault.

Jon B

One of our 'older Hudson' owners will jump in here, but for the time being let me just say that the fuel is pumped to your carburetor from the tank by a vacuum tank, not a mechanical fuel pump. Vacuum for the tank comes from a connection in either the manifold or the carburetor (I'm guessing, here! Someone will set me straight soon enough.)



If any of the metal lines are damaged, of course, you'll have a problem. If, for example, the car has sat unused for years, a certain amount of scale will have built up in the gas tank and this will clog the lines, preventing fuel from coming through. Or, if there is a break in any of the lines (due to rust or corrosion, for example), you will lose vacuum, and suck air instead of fuel.



The vacuum tank itself (attached to your firewall, I believe) may indeed have a leak, possibly caused by a warped or damaged lid or cover, or by a damaged seal. One thought would be to visually look around the perimeter of the cover to see if it's fitting tightly. Possibly you could fill the leak with a silicone sealant, temporarily, to see if that helps.



Soon enough, though, someone will hop in here, tell me I'm full of hot air, and give you the REAL story!



Incidentally, you may wish to join the Essex discussion group on the internet at http://autos.groups.yahoo.com/group/EssexSuper6/ , and you might also want to become a member of the Hudson-Essex-Terraplane Club if you are not already a member: http://www.hudsonclub.org/

Unknown

Thanks will keep "eye" open. Signing off now to follow up your points JD

EssexAdv

if you go to http://hudsonsuper6.tripod.com/ you will be able to download a copy of the Stewart Vac Tank Manual It is for an older model but the method of operation is the same. Send me an email if you need more help.

EssexAdv

Sorry, forgot to give my email address EssexAdv@adelphia.net

hudsonsplasher1

Jon is on the right track, I'll just add my 2 cents worth. This is an oversimplyfied explanation, but here go's. Your vacuum tank has a float that controls a valve. when the valve is open the vacuum from the engine draws gas up from the gas tank, and as the float rises it will close the valve and allow the gas in the vacuum tank the flow down to the carb. by means of gravity.Tipically these vacuum tanks work quite well. If your car hasn't run in some time, you may want to clean your fuel system, including your gas tank and your vacuum tank. Check to make sure you have a good seal on the lid of your vacuum tank, and all connecting tubing.

Another thing you could try is, take the top of the vacuum tank off, and fill the tank with gas by hand. Start your engine and see if it throttles up. The solution will be a process of elemination. Hope this helps, good luck. Gene.

Unknown

I have a 31 Hudson 8 with the vacuum tank. Mine had not run for some years when I got it and it wasn't getting more than a few drips of gas. I took the tank apart to try to find the problem. First thing is the cover gasket was not sealing. Easy to cut your own from gasket material. Still no gas. I took the gascolator off the bottom and found the screen to be completely plugged; cleaned it. Still no gas. I shot some air into the outlet of the gascolator and presto, gas started to flow. It was all plugged up with crud so I cleaned the whole tank out. The float is connected to the cover so be very gentle and careful removing the cover; pull it straight up. After you get the tank cleaned out, add a bit of gas to the vacuum tank to prime it then start it up!



good Luck

Steve

Park_W

One of the most common problems with Stewart vacuum system cars that have sat for a while is also one of the easiest to remedy... there's a flapper valve at the bottom of the inner tank, and old gasoline that's turned to varnish "glues" it shut. A little carb cleaner or similar solvent to clean it up solves the problem.

Geoff

With all due respect to the comments made above, the problem should first of all be ascertained as to whether it is actually the vacuum tank at fault. It would more likely be the Marvel carb that is the problem otherwise. You need to find out if fuel is flowing into the carburettor by taking off the float bowl cover and depressing the cork float. There is a gauze filter at the inlet of the carb which should be cleaned out. Take out the brass cap under the inlet and clean the gauze. Be careful as you are working with old and brittle pot metal. The vacuum tank holds about a quart of fuel in the bottom tank, so you need to run the engine and see if it is filling up. Simply run it for a few minutes, and then drain the tank and see how much is in it. My experience with Marvel carbs that have sat dry for lengthy periods is that the internals swell up, and the flapper valve is probably not operating properly. If you do trace the problem to insufficient fuel, the Stewart vacuum tank data referred to above is of no use, as the '29 models have a leverless system. However, the bottom flapper is worth checking out, as it could have a bit of fluff or crud stuck in it, or indeed stuck shut, but I doubt it is stuck, or you would not get any fuel flowing at all.

Geoff.

Unknown

Thanks to all for their advice. As the vehicle has been "idle" for some considerable time it would indicate that provided I follow up all the excellant advice I`ve received from you all the problem ( being an optimist) will be solved. Will post result later - probably after the weekend- if I`m allowed in the garage "to play" Thanks again JD