Creating pump spray with Hobbs switch?

GTMac Fahrvergnugen

976 posts · joined Nov 2004 · 9 Jul 2008, 8:02 pm

#656658

Guys, trying to get my head around this one..............not with much luck.

Have the normal pressure bottle mounted in front and a seperate standard push button operating switch on the dash to control it manually.

My radiator for the air to water i/c is front mounted and i want to have water spray on this controlled via boost and a Hobbs switch.

Can this be done considering the Hobbs switch will be switched via engine boost and the actual bottle is already pressurised?

Thanks.

1971 Type 3 Fasty - EJ20T

I love 242HP sleepers. 🤪

How many sets of lights does it take a $229k Carrera S to learn? 😂 UPDATE: Cayman S, M3, B4 now added to the list.

speedster356 Plastic not Classic Racing

1,624 posts · joined Aug 2002 · 9 Jul 2008, 8:23 pm

#656662

Is the standard push button switch 12V?

Spyder-WISD 07-09-05 11.6s @ 125 MPH

Speedster-WISD Nats 05 14.4s @ 89 MPH

Jet cruiser-Coogee 22-09-05 900 deg C @ 110,000 rpm

Weaseling out of things is what separates us from the animals....................Except the Weasel.

1303Steve Scirocco Rare

8,650 posts · joined Aug 2002 · 9 Jul 2008, 10:03 pm

#656677

Hi

If your running an after market ECU you could use an output from it or the hob switch would work as well.

Steve

GTMac Fahrvergnugen

976 posts · joined Nov 2004 · 9 Jul 2008, 10:48 pm

#656683

speedster356 wrote:Is the standard push button switch 12V?

Peter probably confused people when I said standard push button switch. I am or was hoping to use the VW dash switch which is the combined turn wipers on/push for water spray. So in saying that yes its 12V but nothing to do with the spray action.

Steve, running Microtech so dont think there is any extra outputs or capabilities to run something. Just thought a manifold line to the Hobbs switch would do the trick but getting it to run in conjunction with the pressurised bottle is my dilema.

1971 Type 3 Fasty - EJ20T

I love 242HP sleepers. 🤪

How many sets of lights does it take a $229k Carrera S to learn? 😂 UPDATE: Cayman S, M3, B4 now added to the list.

1303Steve Scirocco Rare

8,650 posts · joined Aug 2002 · 9 Jul 2008, 11:24 pm

#656684

Hi

Why not fit an electric pump to your washers? Leigh Harris wrote a good article on doing this to a bay window. read it hear http://www.clubvw.org.au/how_to_modify_those_windscreen_w.htm

Steve

speedster356 Plastic not Classic Racing

1,624 posts · joined Aug 2002 · 10 Jul 2008, 6:52 am

#656694

Got ya, the Microtech should be able to switch at a set boost depending on what outputs you are using now. Setup a small washer style pump with relay? switch it through the Hobbs switch.
You could just put in a new system with a aftermarket washer bottle with combined pump, quite cheap at somewhere like Supercheap etc.
I did this in the Spyder for an intercooler spray. I manufactured a 3ltr alloy tank (you go through a lots of water when on boost a lot!) and fitted the pump from a cheap screen washer unit. I used STI intercooler spray nozzles as they gave a nice misted coverage as opposed to the dribble that the windscreen washer nozzles tend to do.

Spyder-WISD 07-09-05 11.6s @ 125 MPH

Speedster-WISD Nats 05 14.4s @ 89 MPH

Jet cruiser-Coogee 22-09-05 900 deg C @ 110,000 rpm

Weaseling out of things is what separates us from the animals....................Except the Weasel.