pumping water with a fuel pump

[ONEBADBUG]

For reasons I won't bother to explain here (Chumpcar), I need a really cheap water injection system. I made one for Bonneville using an old fuel injection pump, and it failed right at the end of the event. Now, it was old and crappy in the first place, so it might have failed no matter what. My question is, has anyone used a standard injection pump for water for any length of time? Mine needs to run 24 hours.

[hotrod]

How cheap are you looking to go?

You can fabricate a low buck water injection system with easily available 12V pumps used in RV's to pump water for the faucets.

http://www.amazon.com/SHURflo-2088-422-444-Classic-Potable-Water/dp/B0006GK5NA

Their peak pressure is about 35 -45 psi on the low end up to about 80 psi on the top end depending on what you get. If you want a bit more flow and pressure you go to the higher end pumps but I've built simple WI systems with the budget pumps and they work just find if all you want is a bare bones system.

You will want to inject between 15% - 20% of your fuel flow in most systems with high power applications taking as much as 50% of the fuel flow.
You can get simple spray nozzles from Mc Master and Carr.

Larry

[Moxnix]

Snow Performance pump?  Not spam, but there was some verbage on here about them a few years back.

[Seldom Seen Slim]

I'm wondering what OBB wants the pump for.  If it needs 24 hours continuous -- there aren't many race engines that run like that 'cepting LeMans and maybe a few others, so  --  maybe he's building a motor to run the pump for farm irrigation, not a race vehicle.  Heck, he might be putting together a project for a science fair.

[Moxnix]

www.chumpcar.com

[Speed Limit 1000]

How much water do you plan on in 24 hours? A soft drink or other tank with a high pressure CO2 or N2 with a regulator and then you do not need a pump.

[McRat]

Snow systems are fairly cheap, IIRC, but if you must use a "cheap/free" non-water pump, perhaps you need to add a lubricity? agent to the water.  IIRC, windshield washer fluid has some lubricity to it.

That ChumpCar stuff sounds great.  But even junk cars are over $500 now.  How do they determine the $500 value?

[dw230]

Claiming fee?  Looks like someone jumping on the 24 Hrs. du Le Mons deal.

DW

[ONEBADBUG]

I'm wondering what OBB wants the pump for.  If it needs 24 hours continuous -- there aren't many race engines that run like that 'cepting LeMans and maybe a few others, so  --  maybe he's building a motor to run the pump for farm irrigation, not a race vehicle.  Heck, he might be putting together a project for a science fair.

It's an old Karman Ghia, the race is a full 24 hours, and the temperature will be in the 90's. Since the whole car is supposed to be $5oo, I can't show up with a Snows system. You guys would love building a car for this series. The rule on custom made parts is: if you can build it in a regular shop with regular tools, it's allowed. Thus my plan for a junkyard fuel pump, and other cheap stuff. I plan to have the pump run continuously and have a temp switch spray water in the fan, and a vacuum or throttle switch spray in the manifold. I will buy a pump ($10 at pull n save) and run it in a bucket for 24 hrs straight to test.   

[hotrod]

Then your best bet might be to find a junk yard that has old campers and RV's and pull one of their 12v water pumps used to supply drinking water to the sink. It should out perform a fuel pump -- and as I mentioned I have successfully used them for water spray and water injection systems.

Larry

[ONEBADBUG]

I had not thought of looking for used one, good idea. Someone mentioned water soluble oil, that's a good idea too.

[Dreamweaver]

Chump racing , sounds right up my alley

The $500 thing sounds sketchy tho.

[McRat]

Another coolant might be machining coolant.  It water-based that you mix usually.  That has very good lubricity for a water product.

$500 would be refreshing.  If I walk into the garage to look at our truck, $500 evaporates from my wallet before I get all the way in.

[ONEBADBUG]

Yeah, "Band-Aid" from our saw should work great. I'm about $3000 into my $500 car by now, but safety things don't count towards value. Cage, Belts, Fuel Cell, etc. I am having to be creative to make a 40 year old air cooled car remotely competetive with a BMW or Miata.

[manta22]

I used a Carter fuel pump in a water cooling system for a portable diffusion pump but, after two pumps failed, I checked into the pump's construction and found that it was a type of pump that uses the fuel as a coolant for the motor. They circulate the fuel through the inside of the motor case as well as in the pump section so the water was actually being circulated in the pump. The 12V caused a small electric current to flow through the water (it actually had some ethylene glycol added) and this current eventually erroded the wire braid connection to the brushes. When the brush contact was eaten through, the pump stopped. Lesson learned!

Regards, Neil   Tucson, AZ