Fuel Injector Flow Testing

Post by **Rossco** » Tue Aug 27, 2013 12:30 pm

Can anyone recommend a company to carry out a forensic flow test on a set of injectors.

I don't want them cleaned, I just need to know if there are any issues with them.

Eliot · Post by **Eliot** » Tue Aug 27, 2013 12:38 pm

Marlin motors in Bletchley (where we have the dyno day) have an ASNU machine and will clean and flow test them.

http://www.asnu.com/centres.htm

The problem I found was that the cost of getting a set done for the Rangie was close to the cost of replacing with brand new items.

Post by **Rossco** » Tue Aug 27, 2013 2:27 pm

Hi Elliot

These are new injectors. I suspect one of them is not flowing as it should and has caused one cylinder to run lean to the extent it's caused detonation and destroyed the piston.

Eliot · Post by **Eliot** » Tue Aug 27, 2013 2:38 pm

ASNU machine should be able to do that. They run them into something like a burette and tell you how much they flowed.

Eliot · Post by **Eliot** » Tue Aug 27, 2013 5:08 pm

Also it shouldn't be too difficult to make your own test bench - 500ml measuring cylinder, fuel pump, filter and a small swirl tank.

From memory megasquirt has a fuel injector test mode on it - or even just megsquirt connected to the stimulator would run them nicely.

If they are high impedance you could run a static flow test by simply connecting them to 12v directly.

Here's a flow test on an a ASNU - as you can see, they just squirt them into a lab measuring cylinder:
http://www.youtube.com/watch?v=hxWpYr6yMaM

http://www.ebay.co.uk/itm/3x-500ml-Tran ... 763wt_1399

Post by **Rossco** » Tue Aug 27, 2013 7:39 pm

I've got a Megasquirt somewhere in the workshop but have never played with it.

You offering any assistance with this one Elliot?

Having said that they are 15.6 ohms so could do the static test......now where did I leave that spare M5 fuel pump?

Quagmire · Post by **Quagmire** » Thu Aug 29, 2013 11:29 am

My Dad and I did this with some old Vectra injectors we were fitting to my Landrover.

Used a spare EFI pump and filter, the Vectra fuel rail and an old Mitsubishi PLC programmed to pulse them on and off for something like 500 pulses. Squirting into clean jam jars.

Used White Spirit as a test fluid and weighed each jar before and after testing. They all flowed to within a couple of % of each other which was nice.

Obvious ways to reduce error are to measure a larger quantity of fluid, and use scales with the smallest unit of measure you can find. Also temp would have an effect I guess.

MS2 and up has a test mode I believe (I only have MS1

)

DaveEFI · Post by **DaveEFI** » Thu Aug 29, 2013 12:34 pm

Would you actually need to pulse them just to measure flow rate?

Eliot · Post by **Eliot** » Fri Aug 30, 2013 6:51 am

No you don't. but i found another video for the asnu machine and they seem to test the flow rate at different duty cycles in addition to wide open static.

kiwicar · Post by **kiwicar** » Fri Aug 30, 2013 9:32 am

Eliot wrote:No you don't. but i found another video for the asnu machine and they seem to test the flow rate at different duty cycles in addition to wide open static.

I would have thought that that would be very handy for accurate mapping.
Best regards
Mike

r2d2hp · Post by **r2d2hp** » Fri Aug 30, 2013 10:49 am

Would have thought it best to measure using pulsed as the injector could be slow to react and just running fully open would not show this up