erbssr: 3/3/2000 - 1:35:45 PM
You said in an answer to an earlier post that you ran dual 94's with 48 jets and 6.5 power valves. I just talked to Flathead Jack & he told me to plug the power valves. He says that power valves open at 6'vaccum and a flatty draws at least 9' at idle. He says with power valves you are dumping enough fuel for a 440 Cubic inch engine!!! That's why most flatheads run too rich. I ordered 2 plugs from him & will give it a try.Anyone else heard of this?

Flat32: 3/3/2000 - 2:02:55 PM
Oh my God. I also talked to FJ and he sold me a pair of his plugs and a set of jets he said would be 'right'. Figured I was all set having 'expert' advice and all. Absolutely wrong. My motor didn't have enough power to make it into the garage. Testing in a field I could only go in reverse. Didn't even begin to run right until I took out Jack's plugs and put , then stock, power valves back in. BTW, the jets he sold me were 46's and they were way too lean. That day I rewrote the book of cuss words. Go to and their tech pages to learn about power valves.

Roger: 3/3/2000 - 3:17:08 PM
I have plugged one carb in a dual setup but you need a carb with a power valve. You can't plug them both.

AV8Paul: 3/3/2000 - 4:14:36 PM
About a year ago I too bought two plugs from Jack. He recomended .042 jets for my 221 basicly stock FH. The car ran like crap, So I put in some .051 jets and it ran much better. Doesn,t make much more power over a single 2 bbl, But it runs smooth and gets good mileage. I'm going to contact Jere Jobe and get His advice on powervalves.

Harlan: 3/3/2000 - 5:35:32 PM
Jack strikes agen. You can get power valves that open clear to 3.5 so what has 9lb to do with it.My flatty pules 14lb at idle. I dont know but I figure the power valves at throtel posithion.on the road. If you throtle is open or you load is high enought to drop you vacume to 3.5 then they open and richen you fuil but do not stay open very long. Some one here is a lot smarter then me on carbs but I could not get mine to run with out power valves.

Arrowsmith: 3/3/2000 - 11:17:22 PM
I use 49 jets after getting 46 jets from Flathead Jack I was useing one power valve untill Jwl convinced me that they don't dump gas into the motor. the gas is pulled in by vacuum just like the other fuel mixture so it can't dump in fuel. I am now running both power valves but don't remember their numbers.

rumble seat: 3/4/2000 - 8:36:32 AM
erbssr: You might want to try Stromberg 97's since they don't have this problem. Their power valve is brass and is mechanically operated. They don't have the power valve rupture problem the 94's have. Their throttle response is instantaneous, they don't exhibit the dreaded sticking throttle syndrome coming off idle, and pull considerably harder. Just my opinion.... rumble seat

BILLY: 3/4/2000 - 9:26:16 AM
rumble seat, I'm With you. I have been running the 97ís on every flathead I have ever built. For me they work just fine.The throttle response is instantaneous with no Hesatation off idle. What more could you want.

BILLY: 3/4/2000 - 9:51:05 AM
erbssr,On the '97' you need to get rid of the stock Needle and seat and buy (Gross jets) they use a stainless steel ball and spring. These things really turn off the fuel at float level.

TomT: 3/4/2000 - 10:27:38 AM
I've read that the leaking problems with 97's are usually the result of damaged housings and shoddy rebuilds. The chapter on carburetors in Tex Smith's book mentions the three plugs as being a major source of leaks and suggests that the best fix is to reface these areas so there is something flat to seal against. It also mentions trueing up the base and bowl sections so you get a good seal against air and fuel leaks.

BILLY: 3/4/2000 - 11:10:36 AM
TomT: With a carb this old and much Abuses you have got to check everything. From throttle bushings to matting surfaces.

TomT: /4/2000 - 1:25:19 PM
Sure, you SHOULD check everything, but that doesn't mean that most of the Stromberg 97's that leak HAD everything checked. Even charges extra for milling gasket surfaces or installing oversize throttle shafts. Anyway, the point is that BROKEN Stromberg 97's leak, and a lot of them are (or were) broken.

erbssr: 3/4/2000 - 1:26:02 PM
With the fast throttle response it sounds like the 97's may be great , however, I already have about $300 invested in 2 94's

32tom: 3/4/2000 - 4:12:11 PM
In the early days of hot rodding pre 80#s the junk yard was the source of parts (and problems). junk yard carbs were worn out and leaked dried up gaskets etc. so back to the yard same thing soooo the gospel was all 97's leak. the same thing for mechanical brakes. the parts got worn and never lubed soooo mech. brakes are DANGEROUS. I'm not in favor of mech brakes but Americans put millions of miles on these brakes and carbs. lack of maintenance and operator error contributed to many of these wives tales. my 97's dont leak and I put lots of miles on a 36 w/mech. brakes. in the same vein all flatheads dont boil over. just my opinion

rumble seat: 3/4/2000 - 8:31:38 PM
Flat32 points out using a Gross fuel control assembly in place of the Stromberg standard needle/seat. I don't use them, but stick with the stock needle/seat assemblies with a viacom tip. I believe the main reason the Stromberg 97 floods (due to a sticking needle seat) is excessive fuel pressure. These old FH carbs, both the Stromberg 97 and the Ford 94, were designed to operate with a maximum fuel pressure of 2-1/2psi. Exceed this and performance and mileage will be affected. We all know that a good stock FH fuel pump will deliver in excesse of 3-3/4psi. This exceeds the design pressure and the needle system will sometimes fail to control this much pressure (the needle is forced off the seat and/or stick). Due to the design of the float system on the Ford 94 (better location of the float fulcrum), it is usually able to control a somewhat higher pressure than the Stromberg. But the Stromberg 97 design won't. Hence they flood and get a reputation as a flooder. All you have to do is to use a fuel pressure regulator set at 2-1/2 psi and you won't have any problems. You should run one regardless of which carb you run..... especially if you're running a Carter brand stock pump or an electric pump. Both furnish considerably more psi than the carb was designed for. erbssr points out they have a reputation of catching fire. True..... One of the main reasons the Stromberg got the reputation of catching fire due to leakage, if we discount the flooding due to excessive pressure, is usually due simply to an incorrect float level setting. Set the fuel level too high and the air horn/main body gasket soon becomes soaked with gas. This soaked gasket weeps gas down the front of the carb. If you're running dual carbs with the generator in the stock position, the front of the front carb is very close to the back of the generator. We all know the generator brushes arc as they contact the commutator. Combine the brush arc with proximty of gas fumes from the weeping gas on the front of the carb and you're begging for a fire. If you set the FUEL level at 1/2 inch, the fuel level is low enough it won't soak the gasket and drool down the front. This has to be done with the top off the carb with the engine running. BE CAREFUL OF FIRE WHEN PERFORMING THIS OPERATION. Or, if you running an electric pump, you can adjust the level with the engine dead using the electric pump and a syringe (to suck up fuel out of the fuel bowl). (I know everyone out there is aware to not pry against the viacom needle when adjusting floats.) Many of us set the FLOAT LEVEL (top of float) at 1/4 to 5/16 inch and call it good. Usually this makes for too high a fuel level and soaks the gasket. I set them at this dimension only for start up and then set the fuel level at 1/2 inch. No flooding and no fires. Just my opinion... rumble seat

Roger: 3/5/2000 - 10:22:51 AM
When I was a child growing up around my Dads junk yard, I can not tell you the number of times someone would come in looking for a carburator because theirs was bad. The first thing they would do was to hammer on top of their old carb because the needle valve was stuck. I've seen 97s and 94s with the tops mashed in. Nobody ran filters. My Dad used to tell us If I ever see you boys beating up a carb like them idoits I''l whip your tails. Thats the problem with a lot of these old carbs. I have an old manafold with 3 strombergs on it. Its sitting on a shelf out in Dads old office. he bought it from a man back in the 50s. All three carbs have the top caved in and the man told Dad, I just can't figure out whats wrong with them they don't work right like they are supposed to. I wonder why?

Tom: 3/5/2000 - 11:25:59 AM
rumble seat I don't understand if Iím looking at the carb(THE FLOAT) how do I set the level where do I Measure from do you put something across the top and Measure down or do you just adjusts the fuel to be below the carb top gasket line. Maybe some one can post a picture.

mr bill: 3/5/2000 - 2:07:04 PM
Every '94 that I have seen has marks on the outside just above the needle valve where they have been hit to free the needle. I am running the newer style flapper valve. It has a Teflon flapper instead of a needle. It is not suppose to stick. I got mine from Vintage Speed but a carb rebuild kit that I got from Mac's also came with the flapper type.

rumble seat: 3/7/2000 - 8:06:10 PM
Tom: Sorry about not getting back to you right away, but got waylaid in the garage.... again!! Setting the float level on a Stromberg 97. Dry, or start up setting: With the top (the air horn) of the carb off, push against the float tang GENTLY so that it closes the needle. If you push hard you'll damage the viacom (like neoprene) on the needle and ruin it. Now measure from the gasket surface of the main body, without a gasket, to the top of float about 1/4 inch from the end of the float that's on the opposite end of the needle seat assembly. This should measure 1/4 to 5/16 inch. Adjust by bending the float tang up or down as needed... being very careful to not press the viacom needle into the seat. This is the dry, or start up, float setting. I'm assuming you don't have an electric pump in the following. All shop manuals state to have an extinguisher near by... just in case. Install the carburetor on the engine and just lay the top of the carburetor with one screw to hold it down. Start the engine and let it warm up and to stabilize the fuel level. With the engine idling, remove the top very carefully to prevent sloshing gas out of the carb. Now measure from the gasket surface of the main body down to the gas level being very careful to not press against the float (it'll cause an inrush of gas that could slosh over out of the carb). Measure to the gas a distance from the float and the side of the carb. This measurement should be 1/2 inch. You'll notice the fuel is pulled upward somewhat and is attracted to your scale (it seems to be sucked upwards onto the scale). This is normal for liquids and is called the meniscus. It is not what you should be measuring to since it'll be about 1/32 to 1/16 inch higher than the level of the fuel. Measure to the level of the fuel a distance away from the side or float. When you're bending the float tang to adjust the float while the engine is running, you have to keep the needle shut while you bend the tang, but you can't pry the needle into the seat. If you pry the needle into the seat, you'll ruin it.... if you bend the tang without the needle on the seat, it'll shoot gas into the carb and could easily flood! Interesting to say the least. It's a lot easier if you have an electric fuel pump. Just install the main body on the car leaving the top off. Turn on the fuel pump and fill the carb. Measure the fuel level. If you have to bend the tang, shut off the electric pump and do whatever bending is needed. Suck some gas out of the bowl and turn the electric pump back on. Measure it again. A lot simpler and safer. Hope this helps.

rumble seat: 3/7/2000 - 8:13:26 PM
mr bill: I tried a couple of those flapper type assemblies and had some trouble with leakage past them. I stick to the viacom needle. The reason they always used to stick was from excessive fuel pressure. We used to think it was from dirty fuel since they wouldn't flood very often if we ran a fuel filter just before the carb. The fuel filter was actually absorbing the fuel puslations and reducing some fuel pressure. I run a fuel filter at the tank, and a fuel pressure regulator set at 2-1/2psi between the stock mechanical fuel pump and the fuel block. I've had this pair of 97's on my FH for nearly 50,000 miles with never a flood or sticking needle. Matter of fact, I've build probably a 100 of these over the last 5 years and none have ever had any flooding or sticking needles.

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