Hello Guys.

A few more words about the PST air trap.

The aluminium assembly top has an o'ring that seals the bottle. The plastic cap has no sealing function.
On the following picture, you can clearly see the difference in diameter between the O'ring and the bottle opening ( red arrows ).
This is what creates the sealing by exerting a pressure on the bottle neck walls ( green arrows ).



This pressure is high enough to make the aluminium assembly hardly impossible to remove by hand.
I recommend to put the aluminium top in a vice and gently pull the bottle with some side motion to remove it.

There is no possibility of leak from the nipples. They are oversize, fastened into the 1/3" aluminium top and glued in position ( red arrow in the next picture ).





The filter assembly consists of a large falter membrane which surface is about 5 times larger than the UAT filter bags. This membrane is folded around the fuel pickup and offers a much higher flow capability than anything else I've seen so far.



The pickup is a large brass tube that is tapered onto the main nipple. Is has an additional filtering clunk at its end.



Tips to get the UAT working correctly for the 200N+ size engines

The pickup clunk shall be positioned far away from the filter end to get a proper filtering effect ( red dot in the previous picture ).
The filtering element is sometimes pushed too much onto the aluminium cap and the clunk is too close from the filter end ( red arrow below ) thus offering a limited air trap effect.



Also the filter might itself need a bit of tweaking to improve the air trapping effect. Just add tow safety wires at the extreme ends of the filter after having centered the clunk correctly ( the red dot shows the position of the clunk and the red arrows the additional safety wires )



Here is the end result: A tight wrapping of the membrane that does not show the brass clunk...



This system is to me the more appropriate for the 200N+ engines available on the market. This is because of three essential items:

1.The 250 ml bottle ( large, rigid and transparent ) that provides a good buffering affect
2. The size of the nipples and the pickup
3. The very large air membrane surface that allows a large flow through and thus less possibility of cavitation.