I have fuel pouring out of this part of carbs. and am wondering if there is simple fix or if I need to start pulling off the intake manifold to get to it. I tightened the brass not on top it was loose but it didn't help. Also what is this part ?
Thanks
Lou

 

That's the needle adjustment for the auxiliary enrichment carb (Choke carb), see Auxiliary Enrichment (Thermo) Carburetter - SU Carburetters for details.

Check the settings and float level etc.

 

As above this is the starter carb, it draws its fuel from the base of the front carb. This can only flood if the front carb is flooding or possibly the fuel level is too high.

If you remove the float chamber lid from the front carb (the one with the bolt in the middle with the pipe that routes to open area below the ending) you can check the needle valve and reset the float level which if my memory serves me correctly should allow an 11mm (7/16") bar to be inserted between the metal tang which the float pushes up and the top of the carb if that makes sense.

Its also worth removing the brass float and making sure that it hasn't leaked and filled up with petrol making it sink.

If you have screwed the centre of the starter carb down you will have altered its adjustment and this will need to be reset, I can't remember exactly how to do this but I think you had to warm the engine up and then engage this with the engine running (by shorting out the otter switch on the inlet manifold) and adjust until the exhaust smoke is black.

 

Thanks for the info. I realize that a stuck float will cause fuel to overflow & I thought that that pipe on top would allow a small amount of fuel to drain off. There is so much fuel coming out from the starter carb. I wasn't even thinking the floats could cause that.in less than 15 seconds there is a very large puddle of fuel on the ground I was sure a fuel line had come loose but that's not the case. It kind of concerns me that if the float problem happened while driving there could be a bad fire as the fuel just pours out. I'll check floats and I almost hope that's not the problem.
Lou

 

Check you needle valve too, it may not be shutting off properly.

 

I'm going to pull the float out & see what's going on. A few months ago I had a lot of work done to the car & part of that was to replace the the jet with the Grosman type but I'm not 100% sure that got done I'll find out soon enough. I also found out that they make after market floats for those SU's my plan is to replace any seal or part that could lead to such a major fuel leak. I already have replaced all hoses and conections at fuel pump, a new aluminum line from pump to a new glass filter bowl and all hoses and connections to the carbs.
Thanks
Lou