Stromberg 97 carb questions
 

I am running dual 97's on an Edelbrock slingshot intake. Manual fuel pump with backup electric pump (only used if necessary) and pressure regulator set to 2.5 lbs and pressure gauge. New 6 volt pos ground pertronix crab distributor.

This is a new setup with good used engine. Redone carbs (prev owner had done and never run)

Just got it running the other day. Was running strong then all of the sudden started sputtering and misfiring when came to a stop. Then died. Started up but seemed like flooded and repeatedly died. Till I ran out of battery.

When towed back home jumped battery and it started right up and seemed to run fine with 2.5 lbs fuel pressure.

Noticed that fuel pressure gauge was reading 0 even if turned on electric pump. when I was having issues. Could one or both of needle and seats stuck causing flooding and no pressure on gauge?


Also What is the correct length accelerator pump linkage. Both carbs are different. The front carb one was to long even if installed on the lower winter/summer setting (so long that accelerator pump bottomed out before reaching WOT. The accelerator pump arm had a slight bend so I straightened it so it now gets WOT but still have 2 different length rods. I checked my original 97 carb from stock motor and that rod appeared even longer?

Re: Stromberg 97 carb questions
 

Usually if a needle is open or a float has a hole fuel pisses everywhere [ask me how I know] . Max hopefully see this and will have the answers, also you need to check what jets and power valve you have, I use grose valves instead of the needles.
Pertronix on 6volt Pos.. Mmm now you need to speak to Jim.

Re: Stromberg 97 carb questions
 

for the 97 the rod is 3-13/16" uninstalled.

Re: Stromberg 97 carb questions
 

You probably have a liquid filled pressure gauge. They often give false readings when warm/hot because the liquid inside expands and counteracts the fuel pressure sending the needle to zero. If your inlet needle valves were stuck closed, your inline pressure would be maxed, not zero.

You may be able to fix the gauge if it has a rubber plug on it. You can burp the pressure out, or empty some of the gauge fluid.

At least that will put you partly on the road to diagnosis.

Re: Stromberg 97 carb questions
 

Yes the gauge is liquid filled but there is a small vent hole in rubber plug to vent it. I had also removed the plug while this was happening.


I was thinking the needle and seat may have stuck open thus flooding the engine. (too much gas)

Re: Stromberg 97 carb questions
 

Strombergs are very sensitive to fuel pressure . . . and many fuel pressure regulators are not really accurate at the low pressure levels that we run Strombergs at. I would use a max of 2 lbs of pressure - and make sure you have a quality low-pressure regulator. If you have one of those cheap chrome ones with a dial on top . . . who knows what pressure it is actually delivering - as they tend to be all over the place (temperature sensitive, etc).

Re: Stromberg 97 carb questions
 

If it stopped, and later started, take a look at your gas cap to be sure it is properly venting. We have solved this problem several times over the years when we found a radiator cap instead of a gas cap on the tank. If you have an in line filter, replace it with a new one. I am not a fan of the Stromberg 97 carbs. They are tough to fix, particularly if you don't have the special tools, such as the jet wrench. They were popular with rodders because the shape made room for the generator. We recommend a properly sized 4 barrel with a mechanical link to the secondaries.

Re: Stromberg 97 carb questions
 

I ran into a similar problen with a tri carb system for a 294 engine awhile back. I made 1" spacers for all three carbs. this did 3 things raised the carbs off th intake making the progressive linkage easier to install allowed a vacuum line for the PCV system Carb vac and a spair for the heater controlls an Power breaks. I was just lucky to have a piece of aluminum that big. I should get a good pic of that came out pretty good.