I am building a fuel injector test bench to measure spray pattern and flow of injectors. I would like to use something other than gasoline for my testing for obvious reasons ( )

Does anyone know what the pros use? I need something with the characteristics of gas such as viscosity but preferably without the high flammability. I have heard of "test fluid" but I don't know what's in it. I wonder if I could use Methanol or some similar chemical?

Alan at The Stable has mentioned that he gets his from Gus at Pacific Fuel Injection. the real stuff is expensive, at about $80/liter, last I heard, and I have no idea what's in it. it is also the fluid of choice for storing a MFI pump.

with an MFI pump the compressibility is a critical factor; EFI injectors operate at such low pessure that it might not be an issue...

Rock Valley Oils, out of Illinois, makes fuel system calibration fluid. http://www.rockvalleyoil.com/ Take a look at their product called Viscor 120. Don't know if they sell retail or in small quantities, though -- here at work, we buy the stuff in a drum.

I know that other testing places use heptane, because its specific gravity is close to that of gasoline. I chose not to use it here because its flammability makes it too risky.

For testing CIS injectors VW says to use Shell mineral spirit 135

This online VW manual has lots of good FI info

QUOTE (jkeyzer @ Feb 13 2006, 12:29 AM)

I am building a fuel injector test bench to measure spray pattern and flow of injectors. I would like to use something other than gasoline for my testing for obvious reasons ( ) Does anyone know what the pros use? I need something with the characteristics of gas such as viscosity but preferably without the high flammability. I have heard of "test fluid" but I don't know what's in it. I wonder if I could use Methanol or some similar chemical?

Methanol is super toxic, so don't even think about it.

I'd be willing to bet that in terms of accuracy, toxicity, and flammability, gasoline is going to turn out to be the best fluid to use. Mineral spirits are just as dangerous as gasoline, and heptane is a component of many gasolines.

Use kerosene or Diesel...

Its less flammable, and it will clean them at the same time..

It will not blow up.
It takes some effort to light it on fire.

Rich

Sounds like you don't want to light your foot on fire (again).

If you're only worried about viscosity, that can be measured fairly easly (stopwatch and a cup with a hole in it). Maybe you can find a cheaper fluid that is close enough.

What properties of a fluid are most important for fuel injection?

Specific gravity?
Viscosity?
Something else?

Why not just use commonly available fuel injector cleaning fluid? Or even rubbing alcohol?

QUOTE (jkeyzer @ Feb 13 2006, 03:02 PM)

What properties of a fluid are most important for fuel injection? Specific gravity? Viscosity? Something else?

surface tension...

QUOTE (r_towle @ Feb 13 2006, 10:05 AM)

Use kerosene or Diesel... Its less flammable, and it will clean them at the same time.. It will not blow up. It takes some effort to light it on fire. Rich

I use Kerosene. Works well. We strain it through a coffee filter before we put it in the tester. The Cap'n