??? ON WATER DRIBBLE AFTER PUMP TURNS OFF

[vic@eurosport]

I just got a WI system and tested it out using a .06mm nozzle. When the system is connected to power the injector sprays a nice fine mist. My question is once the power is disconnected from the pump the water doesn't immediatly stop flowing, instead it sprays a small stream out for about 3-4 seconds and then starts to dribble for a couple more seconds.

Also the nozzle is mounted before the TB and this is on a 7psi turbo engine.

Is this normal or do I need to add something inling to stop this from happening???

Any help woulg be greatly appretiated.



Thanks guys,
Vic

[Richard L]

This is normal - The nylon hose expands under pressure and the pump stops, the water stored in the expanded pipe continue to discharge water until the hose returns to its normal dimanesion.

One way to avoid this is to use stainless pipes or braided hose.

[masterp2]

won't braided hose have the same problem?

[hotrod]

Braided hose is rated for 1500 psi so it does not grow much under the pressures we use.

The other option would be to put a solenoid near the jet that closed when the pump shut off. That would trap that line pressure and keep it from bleeding through the nozzle.


That is how I have my system set up. I have the shurflo pump pressurize an accumulator and all the lines to the front of the car, but control the spray by opening or closing a solenoid only about 6 inches of -3 SS line from the nozzle.

The aeroquip braided line I use is much over kill but its teflon lined so I didn't have to worry about which spray mix I ran through it.

Larry

[masterp2]

Thanks larry, the aeroquip is what I will use as well, but with 800 psi possibly. Do you use barb fittings? What fitting will hold 50 bar?

[hotrod]

I had all the lines made up with AN fittings. (the same fittings used on brake systems and nitrous oxide systems)

They seal very well at high pressures, but are easily undone if need be with a wrench. The actual fittings are hydraulic swaged on the lines, so you'll need to go to a shop that specializes in high pressure hydraulics or automotive racing applications to get the lines made up.

Larry

[masterp2]

There are reuseable fittings for the FC807, you can DIY. Did you consider those? Don't know what the press rating would be on the connection, but I think brake lines use them as well, but don't know for sure.