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Injector flowbench test fluid 2

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Emetz564

Automotive
Jan 21, 2004
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I'm in the process of building a fuel injector flow bench.My question is, what would a suitable test fluid be?
 
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I agree with you, DGALLUP. We use N-Heptane to flow the injectors, and Viscor 120B to lubricate the injectors. Bosch ans Siemens use the same.

You are correct - you cannot accurately flow test an injector if the filter is not in place. Our machine (New Age) allows the user to flow the injectors exactly as they operate while in the vehicle. We can change the fuel pressure, the pulse width of the injector, and the simulated RPM.

That being said, we replace every filter when we recondition injectors. We remove the filter prior to ultrasonically cleaning the injector. We then back-flush the injector, while lifting the pintle off its seat. This allows any internal debris to exit through the large orifice at the top of the injector. We install a new, OEM filter, then proceed with our testing.
 
I use stoddard solvent in my ASNU flow bench and windscreen cleaner in the ultasonic bath.It's old and seldom used these days - I have never cured a faulty injector or had any sort of performance change from an injector service,it's just used for testing and and if we have an engine apart we put them through just to make sure they are working,always fit new filter baskets,they are never likely to be changed again.
 
We have used Stoddard, Viscor, and DI water for testing. With the use of DI water, we had to use correlation to oil (Diesel)charts as well. DI water WILL rust parts, and fast! Some of our other systems also had a Nitrogen flow guage. All of these have been integrated into our EDM injector drilling systems.

Hope this helps some.
Scott

In a hundred years, it isn't going to matter anyway.
 
turbocohen.... my post above was intended to explain the processes that we use to clean fuel injectors - in general. There are many different types of injectors, with varying specifications.

To answer your question; whether the injector has a pintle, a disk, or an oscilating ball, like many first generation Multec injectors, when energized, these areas move, creating an opportunity for the solvent used in the back-flush device to enter through the pintle/disk/ball section of the injector and remove any debris that the ultrasonic waves broke free. The debris and solvent exit through the top of the injector, where the filter basket was removed.
 
Hi,

I use to build flow bench for Delphi and perform test all day as department manager so I may be able to help.

The fluids mentioned earlier of the threads are fairly ok, there is a ISO fluid for Diesel that can also be used for petrol test as we proved a few years ago.

To obtain repeatibility and accuracy, the temperature, pressure and test condition have to be really closely controled. I proved a few years ago that every °C out can bring a 5% error( roughly, this is ofcourse not linear !).

This make the industrial test bench fairly expensive, you will be takling about 200.000 € for a good one with full PC control. I know a couple of companie that have invested in such machine to support there development and want to maximize the usage of there bench. I guess they will be happy to help you on that for a fair price.

Regards

Jerome Douay

Jerome Douay
Team74
 
The lab I worked at used stoddard solvent in production and some lab work, other lab activity involved normal heptane.

I built a few gaseous flow benches using nitrogen for static and dynamic flow but there was very poor correlation between N2 and any liquid. Opening and closing times were different and there were other issues.
 
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