Breather tube

[Stempy]

Just been sorting out why my dip stick keeps popping out , stripped the breather system and renewed the tubes ,3 labyrinths ?

Also found at the other end of the breather tube a one way valve had failed , seized as have not need out on the dart for around 6 months ,is this standard?

4C658F90-72D4-4566-A16D-ED39DDFD06F7.jpeg (158.87 KiB) Viewed 5937 times

B84861B7-C847-4851-A4B0-508315985878.jpeg (136.81 KiB) Viewed 5937 times

Cheers

[morini_tom]

The dart has a different breather arrangement to the earlier 350s to better control emissions of crankcase gases.

The crankcase joined by a short tube to a collector box in front of the battery and the rockerbox breathers also connect here. From here, another tube takes breather gases for re-combustion via a labyrinth and then a one way valve and then a T-piece which joins to each carb stub tube on the engine side.

The parts book shows 2 labyrinths but I’m sure mine only had 1. Certainly your 3 is not correct.

If your one way valve is stuck shut then there is nowhere for the crankcase to breathe and this would explain your popping dipstick.

Personally, I would get rid of most of it and revert to a setup like the early bikes- breather tube vented to atmosphere with 2 labyrinths, rocker boxes vented to atmosphere and carb stub tubes either linked to eachother or blanked off.

[morini_tom]

The parts diagram should make my description of the standard setup more clear