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General Tech Stalling, Chugging, Engine Shuts Down

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KVH, I went through the gas overflow several times. It was always a stuck float valve. The fuel only has one way in, and one way to stop flow. That's the float valve. Setting the height of the floats is critical as you've seen, yet the problem for me was debris getting into the float valve between the needle and body, thus allowing a flooding condition. I've since installed a glass filter just before the carbs and haven't had a flooding issue since.
 
I discovered yesterday that my fuel pump is pushing just over 1 psi and when rest, loses all back pressure instantly. So I now have my starvation problem solved I hope
 
I’m curious. How old is the pump? Same style as new ones from Moss?

I just checked mine. 2.4 pounds. Takes at least a few minutes to relieve built -up pressure.
 
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I want to follow up with you all on a revelation I’ve discovered during my fuel pump replacement. About 2 years ago I installed a fuel pump. I thought nothing of it that I would be battling anything related to it for at least a while. A few months after I installed the fuel pump, I experienced the well known flooding from the float valve, and not just from a single carb! This prompted me to rebuild both, replacing the float valves and all. Shortly thereafter I was again flooding from the float valves. I cleared them out, put everything back together and installed a glass filter just ahead of the feed on the front carb. Never had any more flooding since. Recently I posted on this thread, I believe, to check for debris in your float valves. Well a few weeks ago I have been experiencing a lean starvation kind of problem with my car again. I assumed I’m not getting enough fuel. I just took apart my 2 yr old fuel pump. The strange orange reddish debris I found in my float valves has become apparent from where it originated. The dang fuel pump itself!! I don’t know what it is, I’m assuming an adhesive of some kind, but this is what tortured me a few times. Needed to get this out there. I am going to keep the glass filter in place regardless of a new fuel pump.
 

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Nope. it's not the gasket, believe it or not! It's some kind of glue looking cr*p that's just flaking off. That is the very stuff I was pulling from my float valves before I put a secondary glass filter before the carburetors.
 
There are some interesting lessons about these SU carburetors. They’re a great, time tested technology.

There apparently can be material disparity in how SUs respond or require adjustment from one car to another.

I’m now working on my “other“ Triumph, and it definitely seems that the mixture and float adjustments are quite different. Whether it’s the needles or jets, or just how the engines and heads were built and reconditioned, I don’t know, but the dynamics (rich, lean, float/lid clearance, number of flats open) are different. I suppose fuel pump pressure may also play a role.

Maybe just expected. No set formula.
 
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