Checked all that. Short pipe. Ordered new pump. Engine was new old stock as was the outboard pump.
Ordered a facet pump and a new pulse pump.

Where is the pulse tube connected on engine? See photo of pulse tube connected to valve cover on Briggs engine.

Lift height is next to nothing so that can't be the problem.  My guess would be the vacuum pipe to the pump - they need to be short and very stiff wall or the pipe "pulses" instead of the pump diaphragm.

You've got a leak somewhere? Is the pump mounted as close as possible to the engine?

Bugger.
2 new pulse pumps original and a new mikuni cast outboard in the 16hp Briggs and it still won't get fuel to the carb on full chat. (No blocked pipes and breather working).
Gravity feed it and no problem.
Didn't want to go down the electric pump but I fear I have no option.
Unless I'm missing something.

As long as it works I don't care.

That sounds familiar , should work well. BTW with that shaped duct gives some very interesting airflow patterns.

It's alive.

https://youtu.be/GRwRNVZQNT8

I'm just happy if the rudders make the craft go in the rough direction I want to go.
As for self cantering I have arms that can do that.

23% is advised by Barry "The Grand Master" Palmer. I have come to accept that I only disagree with Barry when I still have something to learn.

As infered, being reminded where straight ahead is can only be good.
My car feels around 10% in comparison, which i prefer.

Balanced rudders.
I am told that 25/75 % is an optimum (using the pivot point as the centre). Checked my Sirocco as didn't like the 'over centre' feel. Felt like it was dropping into turns and you'd have to pull it straight.
The two rudders when checked were 29/71 % on measurements.
I made up sone  SS plates to alter the balance of the rudders by moving the relative pivot point to my give basically the same feel as my Marlin III, 21/79.
Sooooooooo much better.
Now feels good with a more self centering action without be heavy.
Nice when a plan comes together...........

I am deeply comforted as I was feeling faint.
Standards man - (Standards).


On a personal note, I feel "balanced rudders"
are often "overbalanced" as I prefer to have
a firm self centering action.
In this way the straight ahead position
is re-affirmed (should this be forgotten) by the driver.

It will perform just like it did before.
Same pivot point.
Would have kept the original if it hadn't have been too high up due to original splitter.
Nick mi old fruit the paint is ordered.
CombiColor red.

Looks like rather a large area to the rear of the pivot point (on the larger rudder) and hardly anything forward, which may make the steering "heavy" See "balanced rudders"