Klowdedsoul

I changed the needles and seats, checked the floats and it still floods. The rods looked discolored but otherwise ok. I pulled a pair of rods from a 750 I have, those are 71x47, my 600's were 70x47 and nothing changed.

projectresto83

The discolored rods are normal. I used to have a 1406 on my 306. Never had a flooding issue, just heat soak issues. I ran it with 10psi fuel pressure for a about 6 months....not by complete choice, didn't have a return line for the return style fuel pump. I blocked it off so it bumped up the pressure from 6 to 10....

Whats the conditions of your step up springs?

Anyway, when you say it floods...describe what you mean by this... what size jets do you have in it?

Klowdedsoul

The springs looked ok to me. I also pulled those from the 750.

It dumps right out of the boosters, almost a steady stream. Jets are original .100 primary, .095 secondary.
I had this problem before, about two years ago. I could see the fuel boiling in the filter and was told to put a wood spacer on it. I had an aluminum one and used that and I could drive for 20 minutes instead of 15 before it would flood out. With a 2" spacer I haven't had anymore problems until now. As far as engine temperature it never passed the middle of the gauge. Now I have a RPM intake with a rear water crossover and an electric water pump and the temperature only goes up to the second line from the bottom.

projectresto83

What did you do when you checked the floats?

Klowdedsoul

I turned the lid upside down and measured the gap from the float to the lid at 7/16" and holding the lid upright the manual said they shouldn't hang more than 15/16" to 1", it looked right to me.

rtintwo

Take a look in this thread and do the test that gunjam talks about for the floats.

https://mustangforums.com/forum/clas...ock-carbs.html

Klowdedsoul

They are good based off of that. The only thing that has made any difference is that I changed the springs to the yellow ones. Now I don't see any fuel at all dumping down the primaries but the running condition remains the same.

Also, with the vacuum gauge it slowly fluctuates between 11 and 12 at idle, 1000 RPMs.