Stromberg 97 Issue
 

This afternoon Flathead Ted came over to check out the Cabriolet, now nearing completion. I fired it up and suddenly it's running rough and gas starts streaming out over the garage floor! Quickly I turned it off, averting total disaster. Undoing the main inlet we discovered an S-Jet inlet valve rather than the regular needle and seat. The carb is a new Stromberg 97, should I look further for any other carb issues, replace the S-Jet with the older style inlet or is there something else I should be looking at. It's made me very nervous around starting the car up! I've attached an image of the car, it's present condition is due in part to the many Fordbarners who have helped me over the years with my questions and requests.

Re: Stromberg 97 Issue
 

The S-Jet is supposed to be superior to the std needle and seat. Needless to say I had one stick on my new style 97's. Cleaned it out and it hasn't given me any trouble since. Is the float brass or black plastic?

Re: Stromberg 97 Issue
 

Re: Stromberg 97 Issue
 

https://i.ebayimg.com/images/g/NzUAA...ZIR/s-l400.jpg
GENUINE STROMBERG FUEL INLET S-JET 97 CARBURETOR

Re: Stromberg 97 Issue
 

i dunno about S-jets, however, it is a well known fact that Strombergs are sensitive to too much fuel pressure. What pressure is the pump developing?

Re: Stromberg 97 Issue
 

Hello Brian, How would I determine the pressure that the fuel pump is producing?

Re: Stromberg 97 Issue
 

Run the outlet of the pump into a pressure gauge. ie remove fuel line between pump and carb, make up a line that will screw into the outlet of the pump, with other end attached to the gauge. Crank engine over, or run it with whats in the carb bowl, and observe the gauge reading

Re: Stromberg 97 Issue
 

The "S" Jet is very close in tolerances and will not handle much debris before sticking. Although they have their shortcomings they will withstand more fuel pressure than the old needle. In testing I have used 7 lbs. without problematic leakage. I suggest plenty of cleanliness and filtering prior to sending fuel through the "S" Jet.

Re: Stromberg 97 Issue
 

Do you have a filter on the incoming line (like one in the glass fuel bowl - if you have a glass fuel bowl) - or one on the out-bound side of the pump? You probably have either debris in the jet itself, or too high of fuel pressure.

I typically run about 2 lbs of fuel pressure with Strombergs (with the older style needle type). I've not done a pressure test like JWL with the S-Jet . . . though my guess is that you'll have issues with 7 lbs of fuel pressure - though there is no way to know unless you put in a pressure gauge. You may need to have your pump reworked - as many of the new replacements have much higher pressures than the originals, or you may want to consider a high-quality low-pressure regulator (which is what I'd do).

PS: Don't go for one of those super-cheap chrome regulators with the rotating top piece - they are junk. ;) I'd use a Holley 12-804 regulator - which you can get at Speedway and plenty of other places. And make sure you have a gauge on the outbound side of it - liquid filled, designed for vibration.

Re: Stromberg 97 Issue
 

Hi there, I have used a couple of the new strombergs and they work perfectly, but you must use a good in line filter ahead of the fuel pump and carb. Have you run the engine before or is this the first start ? I would bet some muck has got into the S-Jet and kept it open. Are those 1933 headlghts on your 1934 cabriolet ? They look longer than 34 headlights. Nice car. Regards, Kevin.

Re: Stromberg 97 Issue
 

I asked about the floats as the early units used a plastic float and they had problems with them. My 97's had plastic floats and when I had my S-Jet stick Stromberg sent me brass replacements. I am also running a Holley 12-804 fuel pressure regulator.

Re: Stromberg 97 Issue
 

Thanks guys, I've taken note of all your suggestions and will post any results. I have a filter between tank and carb sitting inside the chassis at the back. The engine is reconditioned and has only just been started, the carb was new out of the box. Yes the headlights are 33! They were my best pair and I quite like them! That is. until I find a better set of 34s!

Re: Stromberg 97 Issue
 

Its a nice car believe me its a credit to JRs perseverance ,he has his own good Mechanic but I could help if needed with the pressure tester,

Re: Stromberg 97 Issue
 

JWL covered it.
I have tested and used the Neoprene or Viton tipped needles and they will also work fine at 7 or 8 lb. I have always run 6 lb on my Strombergs. With any needle setup, the bowls will run dry at 6000 rpm on the straight of a half mile circle track.
The original steel needles will work forever on the street as long as you keep the dirt out.