Just installed a rebuilt Stromberg OF from Stan Howe. The car started right up and runs great, no adjustments required.
Now the rest of the car does not look good enough for the great looking carb.
Nice looking. The more I see the OF carb the more I want one. What T is that installed on?
It is in a 24 Touring, but we have OF's in our 22 touring and 19 roadster.
thats cool. How do think the OF would work on a speedster with a stock engine?
That looks like the aftermarket aluminum intake. Mine put the carb too close to the frame, so I used a long, flat sander to change the angle of the ports just a little.
In my limited experience, the OF gave no more power than the NH, but much better economy.
That's a good point I did not think about that. I'll check that out next time I look at my carb.
Thanks, Ivan. I missed this post earlier. I have two of your brother's OF's done and returned, I'm getting gradually caught up and should have his last one back to him soon. I'm trying to figure out how to make the steel parts faster then sawing each one out on the band saw and filing them by hand but for now that's the best I can do. Making the seat adapter is time consuming but not like making the steel choke stop. I have the throttle arm and economizer pretty well down to a science to make those but it still takes quite a lot of time. I'm also working on a needle/seat adapter for the 4 and 5 ball Kingstons to put a modern needle and seat in them. The original system is pretty fragile and hard to fix. Did one prototype so far. Now to make some jigs to mount the carb solid and position it so I can mill/drill/tap the seat accurately every time. Just need a day to work on the jig and a day to make some replacement arms and I should have that project done.
Let me know if you have any problems with the OF down the road.
Maybe if you sprinkle some of that Modified Bitumin Roofing Tar on the carb, then the car and the carb will look great together.
Can't sprinkle it, has to be heated and poured. Some of them are coated with it when I get them in.
And some are even nastier.
Uncle Stan -- That looks like the one I sent you.
Yup!!! I figured you were checking to see if I really could do something with Arkansas junk. Did you take a picture of it when I sent it back? It actually was a pretty nice carb. These two weren't bad, just nasty dirty. The bad ones are where the steel parts are all rusted away and there is a big dent in the side of the bowl or somebody has cut the mounting holes out bigger to use it on a different size mounting. Ones like this just take cleanup for the most part. Since I make a new throttle shaft of nearly every one and replace the choke shaft in about half of them it doesn't make much difference if the throttle shaft is broken off or missing. All in a day's work.
This is the kind of thing I enjoy doing. Taking what is basically an unusable piece of junk and turning it into a functioning piece of equipment and at least to some extent a work of art. The money also helps.
Did you try yours out yet??? I'm always curious to see how they run for different people on different cars.
Is there a book out there i could buy on the Stromberg carb, i have a updraft for a speedster and would like to find out all the adjustments thanks
Which model updraft, Curtis?
Found this in my files:
10:00 PM 5/28/2007
The following pages contain an explanation of the principles employed in the Stromberg carburetors, together with a brief description of the different models.
They also describe the procedure by which the requirements of the engine are ascertained and the carburetor setting co-ordinated therewith.
Since in actual service the mixture requirements of the engine are an all important consideration, it has been considered advisable to open the subject with a chapter describing the conditions existing during the intake stroke and showing how the mixture requirements of one engine may be different from those of another.
This information will be found particularly valuable in service work, as it will give an understanding of deficiencies due to engine faults which are often erroneously ascribed to the carburetor.
WHAT THE CARBURETOR SHOULD DO
Combustion Requirements; Vaporization; Mixture Proportions Needed From Carburetor
The carburetcr furnishes the fuel charge, without which the engine cannot operate; it also is the means by which the driver controls the motion of the automobile.
No matter how carefully built the rest of the engine may be, the car will be sluggish, if the carburetor does not furnish the proper mixtures in obedience to each slight touch of the driver's foot on the accelerator pedal.
The responsiveness of the engine and a large part of the pleasure obtained from driving a car depend upon the carburetor.
There are other elements which enter into the operation of the engine. The speed, load, temperature, manifold, and nature of the fuel, each have an effect, and the best carburetor is the one which best graduates the fuel feed, or mixture proportion, to suit these different conditions.
In the early days of the automobile it was believed that one fixed proportion of air to gasoline would give the best performance under all conditions. It is now known that this is not true, and the present success of the Stromberg carburetors is largely due to their ability to give a properly proportioned mixture under different conditions.
The following chapters explain how the mixture delivered by the Stromberg carburetors is con-trolled, and why, and how it is varied to meet these different engine conditions.
Mixtures that can be burned: To burn gasoline or kerosene completely, the fuel must be mixed with about fifteen times its weight, or nine thousand times its volume of air.
In practice it has been found that to get the most power from a cylinder, the weight of the gasoline charge must be 1/12 to 1/14 pf the weight of the air charge, while the most work from a given amount of fuel may be obtained when the gasoline is 1/16 of the air weight.
Illustration (Fig. 1) shows the actual amount of liquid gasoline needed for the best power and for the best economy under full load or full speed, in one cylinder of a 3%" bore by 4 " stroke engine.
For best For best Largest Idling fuel
power, economy at charge that charge.
full power. will ignite.
Fig. 1. Actual size of liquid gasoline charges for one cylinder of a 3)i" bore, 4%" stroke engine; (assuming complete evaporation before ignition).
The fuel charge can be increased considerably beyond these limits before the engine will fail to fire from too rich a mixture, a fuel charge of the air charge being about the limit in this direction.
On the other hand, the fuel charge cannot be reduced very much below the mixture of best economy before the engine will start to miss occasionally from too lean a mixture. While the drawings illustrate the sizes of the liquid fuel charge, the equivalent amounts of fuel vapor occupy considerably more space, but only about 2 per cent of the space occupied by the air charge.
Full power cylinder charge: At full power, with throttle wide open, the air and fuel charge occupy, at the end of the suction stroke, all the space in the cylinder vacated by the piston on its downward stroke.
The space above the piston at the top of the intake stroke is filled with exhaust gas remaining after the previous expulsion, and this exhaust gas stays in the cylinder during the suction stroke.
Illustration (Fig. 2) shows the relative space occupied by the air charge, fuel charge, and exhaust residue at full power with throttle wide open.
Actually they are mixed in the cylinder instead of being separated as shown.
Curtis, almost all of the bronze Strombergs that I have seen have the same basic adjustments. They are: 1. Float height. Depending on the model you have it may have a removable plug on the side of the bowl. Adjust the float until gas just drips out that hole. 2. High speed needle. 3. Low speed needle. 4. Most also have some kind of an "Economizer" air bleed to lean the mixture at idle and give a richer feed under acceleration.
Some where in the carb will be a removable main jet and probably an idle jet. The idle jet is most likely to be plugged but the holes in the main jet also need to be cleaned. Go buy a CHEAP set of acoustic guitar strings. Cut them up and use them to clean the jets. They are the best jet cleaners because the wound ones are bronze or brass and won't enlarge the holes. The steel ones are very accurately sized and work well also.
After cleaning it, install it and with the engine running above idle speed adjust the high speed needle out until it starts running too rich. Turn it in until it runs too lean and then back out about half way to the too rich setting. Adjust the idle screw down to where it will barely keep running and adjust the slow speed needle in until the engine almost dies. Then back it out until it picks up enough gas to idle. Adjust the speed up a little and do it again. When you open the throttle the economizer should close within the first 1/8 turn of the throttle shaft. That will get you in the ball park, you can tweak it from there and it should run.
I reprint the manuals for the OF and LF but don't have other manuals.
thanks alot rick and stan,the car came with a srare but i know that it is missing the buterfly i think i read in the message board that you can reproduce that when i get the car running i will look you up and get a spare done thanks