MTFCA Forum

I'm finally getting back into my '27 touring project and wondering if someone can help me with a confusing Stromberg OF issue.

First, let me say that I'm familiar with the OF adjustments as my Dad has an OF on his '26 Roadster since I was a toddler. Let's just say that was many moons ago?!?!

Second, I should set a baseline letting you know that my '27 Touring previously had a Vaporizer setup. The Vaporizer was problematic on cold starts but ran perfectly once I was eventually able to get it started. I had the Stromberg OF laying around so I simply decided to give up on the Vaporizer.

After replacing the manifolds and installing the Stromberg OF, the car easily starts (and idles well) now but stumbles and hesitates at mid to high throttle speeds. While running at higher rpm, the exhaust manifold will also glow cherry red, which indicates that I'm delivering an extremely lean mixture. I've opened the high speed adjustment past 3-5 turns but it doesn't seem to resolve this problem.

I originally suspected an intake manifold vacuum leak but everything appears to be aligned, sealed with no cracks to be seen. I'm now suspecting that there might be something wrong with the high speed circuit in the OF. However, after disassembling the carb and verifying all jets/passages are clean it still stumbles at high throttle. (I will admit that I don't fully understand how the idle circuit & economizer inter-operate but the high speed circuit seems fairly straight forward.)

I'm hopeful that someone might have some advice that could help me get back to cruising speed with the Stromberg OF carburetor.

Recheck your timing----A cherry red manifold is usually caused by too lean and or retarded timing. Seems like your OF stromberg is OK ----reset to usual settings after timing check---Good luck! paul

I'll check my timing tonight. Thanks!

Between the links in the below posting and itself, just in case refresher for setting the OF;
http://www.mtfca.com/discus/messages/59 ... 1482595964

Thanks Paul...you nailed it! My timing was far more retarded that I thought. It's probably more accurate to say that I'm retarded as TDC was pretty past half way in my timing adjustment range. After adjusting my timing, the engine now throttles up much better. It's nice to have a car that both starts and runs well now.

I also appreciate Mark's refresher on the Stromberg adjustment.

Thanks again!

I ran an OF on my 23 runabout for a year and the only problem I had was the counterweighted needle that rides on the top of the brass float would get stuck on occasion and caused the fuel to dump on occasion. The top of the brass float had some dings in it. Couldn’t find a better float and I installed a U&J ... been that way ever since.