Air leaks and bubbles

[Jardon]

I recently replaced the quick fit connectors on the vac side of my 1s kit with compression ones (thanks Richard). I had been getting methanol leaks from the elbow at the tank end and air leaks at the elbow on the pump. This seems to have worked to some extent but I am still getting air in somewhere and there is constantly a bubble hovering at the pump inlet.

The pump is flowing about 20% less than anticipated too (270cc/min with a 1mm jet and 200cc/min with a 0.7mm jet). This was with the pump just above the level of the methanol.

I'm not sure where to look next. Replace the filter? Are there seals in the pump inlet that may be leaking?

I also notice that the 4mm line on the pressurised side will empty - I guess this is due to vacuum in the intake but I am injecting before the throttle plate. I could try a check valve but will this further reduce my flow rate? My peak boost is 1.4 bar so with the reduced flow I reckon I'm close to the limit for proper atomisation (2 bar differential accross the pump?).

Any tips would be appreciated.

Thanks, Huw.

[Jardon]

So I moved the pump down to the subframe and now it flows 350cc/min (a 30% increase) - Result!!! These pumps really don't like sucking but they blow quite well.

This position below the top of the water/methanol means the pump is always self primed and air leaks/siphoning on the vac side far less likely.

I Recommend experimenting with the position of these pumps - I like how instant the misting is but was disappointed with the flow previously. There is no lag when the system activates - it mists immeadiately with no "dribble". I was considering a larger capacity/"laggier" pump but now problem solved. Thanks Richard if you're reading this.

[Richard L]

Thanks for the feedback.

[Jardon]

No worries - still going strong. No bubbles and performance has never been stronger. Just added a plate diff and bigger intercooler - fun times!