Home Made Fuel Injector Cleaning Machine

[pocket-rocket]

I haven't priced a solid state relay for some time. Are they still pricey? I bet that would have no problem keeping up with the duty cycle

[Superdave]

a relay might be a little slow, this could be done with 6 transistor switches but i don't feel like drawing that one up.. lol


BTW, an injector pulls just under 1A with no pressure on it.

[pocket-rocket]

I think the only limiting factor you are going to run into with the relay idea is the turn on and turn off speed (unless you go with a solid state one). I used to try to reverse step down transformers in electronics class to make a "shocker" and tried to rig something up to turn on and off fast (since pushing a normally open momentary push button switch was not fast enough, and not as cool) to deliver a better shock. I used contacts on the relay (it had about 6 sets of contacts?) that were normally closed when off and went open when powered up to feed the actual coil on the relay. This way when yo put power to it, it would switch states and go open, dropping power to the coil, which would then change switch states again to power the coil, which would switch states again, and so on in a loop. It would only fire for about a second before it would stop until I removed power from it. My thought was it would keep going and going being self sustaining to continue to deliver a good shock, but it didn't work. Ideally I think you might need a 555 timer or some other timer circuit to trigger the relay to get the results you want. I only bring this up because from the sound of the speed those injectors were firing in that video, I think it is going to be too fast for the relay to handle (unless again, like I said, it's a solid state one). BTW, I like your contraption

[60dgrzbelow0]

Superdave... Thanks...

That would be the help I need, Brother!! If you determine the one(s) required are a common electrical item I can get from Radio Shack (The Shack?) or an electrical supply depot...and have the make/model/performance specs that I need to buy them... I would like to know that data when you find out what's what as well on your schematic. I'm grateful for the interest!

[Superdave]

all you really need is 1 relay that can handle a 5-10A load. Tomorrow i'll test an injector and see exactly how much current the coil draws @ 13.8V.


If you want me to draw it up i can do that, it's extremely simple.


I was actually going to build something similar to this a while back to cycle the injectors while they were in my ultrasonic cleaner. I have some adjustable light chaser controllers from old casino signs that would work great as a trigger source.

[60dgrzbelow0]

Thanks robertisaar...

I'm going to have to spend a little time trying dope it all out (trying to id the right type and quantity of relays) and try it on a few non-working fuel injectors.

About this idea of mine and the resulting device that is now built... Now that I know that somebody else dreamed it up first, to be fair, I just sent an email to the REAL originator of this idea...gave him some props for thinking it all up... and let him know that HE gets all the credit for its design...attached is a screen print of my message to the man...

[robertisaar]

depending how your tool is wired, all you need to do is take the sire sending power to the injector, and use it as a signal wire for a relay, and then have the relay do the work, not the tool.

[60dgrzbelow0]

...I guess I should have asked at the outset of this project whether or not anybody else out there in 60*Land has already built one these things of their own design... ....Anybody.....?

Holy Smoke... I think I found somebody...and he is a 60*er...too!!!

http://www.fierosails.com/InjectorTester.html

Its interesting that he chose to use the same general construct that I came up with, right down to using the identical GM Fuel Rail! But with the major differences between the two designs being that I finally mounted all my hardware in an organized 'easy-to-get-around' sort of vertical rack... while his parts and pieces seem to be mounted on a half-an-acre of marine plywood where he has to bend down on his driveway to work the thing.

The other significant issue of difference is that his device can only test one Electronic Fuel Injector at a time... having to use a stop watch in one hand, while holding down the power button in the other, while mine will do at least three and the pulses are pre-timed to exact fractions of a second. And still another issue is that his power/wire set up can only open and close as fast as he can press the trigger on his 12V finger button actuator, while the OTC Tester I'm using can force at least three injectors to fire 100 times in half a second. Like me... he was also very concerned with having a fire hazard with fuel substances under pressure in the presence of a possible ignition source, but I'm not sure how he would control a fire once it started (no Fire Extinguisher on hand), but now that I think about it, just because there was no extinguisher present in any of his photos does not mean he would have one on hand in an actual real-time situation.

I still think he has me beat though on his ability to power one injector open and hold that open condition while the EFI Cleaning Fluid (in his case... he chose to use Kerosene as the solvent) for as long as he wants to flush out the injector ...just as Superdave described earlier in this thread.

I'm still interested in coming up with something... with the understanding that I am not trying to approach some God-awful stoichimetric perfection here since I'm not burning anything...I just want to be able to activate all six injectors...and keep them sort of at WOT for a set time frame.

[60dgrzbelow0]

...the relay network is VERY simple, but since I don't happen to know which terminals of the relays do what off hand I'll let someone else draw it out for you.

...any takers on the Relay Design Diagram and a Complete Parts List?

...as for bypassing the FPR: I would have just used a $15 vacuum pump that way i can vary fuel pressure to whatever I like...

Superdave and I would not agree with you there, as that would have added yet another mechanical/electrical device demanded by the In-Car set-up that I wanted to avoid entirely in my already complex design/build. But to show that this system has great variability in fuel pressure control (from 0-100 PSI), I'll shoot another short video that shows on the Fuel Pressure Gauge just how precisely and constantly the fuel pressure can be varied by simply adjusting the "on-top-of-the-fuel" air pressure regulator.

I guess I should have asked at the outset of this project whether or not anybody else out there in 60*Land has already built one these things of their own design...

....Anybody.....?

Oh ...about trying to more closely emulate all of the cleaning procedures the commercial versions of this apparatus tout... I picked up a set of six, opaque poly-propylene chemical-proof 50ml Graduated Cylinders off eBay for ten bucks yesterday that I'll use for the "Injector Balance" portion of the tests the Big Boys usually perform. I've also got an idea of how to reverse flow the injectors to perform the back-flushing of the EFIs they use as one of their cleaning procedures that I will experiment with on the GM 3.4L Fuel Rail.

The last thing needed is to design is a sort of plastic lid/support hold-down rack in order to not only clean the injectors at 65 C with "Purple Power" as the solvent in my UMAX Ultrasonic Machine...but seal off the top of the S/S bucket holding the boiling cleaning solution too so I can employ using the OTC unit without risking an electrical short of the control unit when activating the pintle (pintel?) rods during the thirty minutes or so the machine runs and do a better job with the caustic solvent cleaning side of the process. I'll shoot the rest of the follow-up images/videos of all this when these other components are in place and are hopefully working.

[robertisaar]

the relay network is VERY simple, but since i don't happen to know which terminals of the relays do what off hand i'll let someone else draw it out for you.

as for bypassing the FPR: i would have just used a $15 vacuum pump that way i can vary fuel pressure to whatever i like...

[60dgrzbelow0]

Some follow up observations on cleaning performance and functionality issues of the HMEFICM over the last few days:

For the latest images (short...visual CLIFF NOTES on this update) go here:

http://s557.photobucket.com/albums/ss19/60dgrzbelow0/HOMEMADEEFICLEANER/

The fuel pressure level is very critical in making the EFIs cycle the cleaning fluid, which is very much denser than straight gasoline or diesel fuel! Anything below 40 PSI lowers the spray level substantially and thereby reduces its ability to properly cycle and clean them. Anything above 50 PSI simply causes the fuel flow to abruptly STOP. I suspect that the cleaning fluid viscosity is causing some internal pressure differential that is just too thick for the EFI electromagnet actuating the pintle to overcome. After some experimentation, I found that setting the Fuel Pressure to 43.5 PSI provided the best results.

Some of the the EFIs failed to respond for quite a while until I realized that either something ugly was trapped inside and blocking the pintle rod from moving up and down...or that the EM Coil portion of the EFI may have been damaged or faulty and incapable of activating the pintle mechanism electromagnetically. In any case, I found that by setting the OTC unit to 100 cycles for .5 milliseconds and rapping on the lower metal casing with the end of a screw driver for 3-5 seconds at a time...eventually ...small droplets of disgusting, brown mung oozed out slowly ...and then very gradually, the fluid spray improved...eventually getting to the point where these poor performers were equal to the other, more 'easily influenced' EFIs on the Fuel Rail.

The presence of this molasses-rusty-looking crap coming out of the innards of a few EFIs prompted me to take one from a set from a 1996 Lumina and bench grind it apart to examine the interior components. My photo bucket listing has all the photos showing that all the parts inside are either made of plastic, nylon and a very high quality surgical-like steel resistant to rust, corrosion and wear and highly responsive to magnetism. Whatever it was that was trapped in the interiors of these poorly performing injectors before cleaning should not be capable of causing any permanent damage at all to them and my confidence is high that even the worst of these EFIs can be made very serviceable again,

I neglected to provide the specifics of how to re-work the fuel to by-pass the resident Fuel Pressure Regulator on the fuel rail, so I dis-assembled one in stages for instructional purposes and have posted images of the procedures as well. Please note that the $20.00 or so that the “Special Security Fitting Tool Kit” cost me from Amazon.com to be able to remove the unusual center-pinned Torx screws has paid me back in dividends because devices like the PS3, Palm Tungsten E2 (battery and damaged screen swaps) and other similar electronic devices all sport these damned security screws as well and fixing them comes a lot easier when you can “break” into them with the correct tool.

This is the “Here's How” on disabling the FPR:

The Fuel Pressure Regulator on this Fuel Rail looks like a “Top Hat” with a vacuum pipe spigot attached to it and is held in place to the Fuel Rail by means of a separate metal ring and a series of “Specialty Security Torx Screws”. After removing the weird little screws, you can lift off the hold down ring and the hat and expose a thermostat looking item...surrounded by and attached to a rubberized fabric bladder. The simple mod needed to bypass all this hardware is to just pluck out the small, round, hardened shiny steel plate that is attached to the central portion of the under side of the bladder unit by a round “hip-joint”. When this small item is gone, fuel will pass inside the open channels of the Fuel Rail unimpeded to all six fuel injectors. That's it. Just put the pressure/bladder thingy back in place, lay the “Top Hat” back over it along with the holding ring; align all the holes and re-install the Torx screws. That's it. But for an even simpler method to do this Mod, you could simply lay either the “Top Hat” or its hold-down ring over some gasket material and an eighth inch flat disk of aluminum and after drilling out the holes, tighten it all down (crossing pattern to even out the gasket).

http://s557.photobucket.com/albums/ss19/60dgrzbelow0/HOMEMADEEFICLEANER/

[60dgrzbelow0]

Nice but a little over engineered... I did something similar to test injectors a while back but didn't use a fuel rail. I took high pressure fuel hose and clamped it to the injector inlet and used a regular DC power supply to trigger the injectors. I was just testing them for leaks though. You could build a simple relay network to trigger all 6 injectors at the same time using an external 12vDC power supply and your tester as a trigger source.

Thanks... and I agree that it looks a bit much... but after working with the thing over the last week, it has just been a breeze to get the injectors mounted, cleaned and unmounted on four full sets (my follow up on all that follows this reply). Super Dave... your idea about some kind of easy to attach and reliable power supply that could do the job of opening and closing all six injectors simultaneously is EXACTLY what I have been trying to get my hands on. I almost snagged a second OTC on eBay this morning...thinking I could just use one unit for each bank of three and that would solve the E=I/R problem or whatever the hell the issues are that are making it not work on all six EFIs at the same time... but the bidding went crazy in the last minute (all the way to being bought at nearly a retail price).

But your procedure intrigues me. I'm just not grounded very well in electronics at all (no pun intended) and I was afraid I would wound the units with either too much of one thing or maybe not enough of the other ... voltage/amperage... electrons-wise. My next post has all the poop on what I've managed to figure out about all this on both strengths and weaknesses (with new photos for the CLIFF NOTED version). I would be grateful for a simple diagram of what it would take to run this thing and hit on "all Six" continuously for about three to five minutes.

As a sidebar (...not TOO far OT) I have several funny stories to relate about my neighbors reactions to seeing me in my front yard-driveway with "FRANK" (short for Frankenstein....or perhaps "The Franken-Jector"....?) working away at cleaning EFIs... I'll have to post them later in the Off Topic Section...

[Superdave]

Nice but a little over engineered..


I did something similar to test injectors a while back but didn't use a fuel rail. I took high pressure fuel hose and clamped it to the injector inlet and used a regular DC power supply to trigger the injectors. I was just testing them for leaks though.


You could build a simple relay network to trigger all 6 injectors at the same time using an external 12vDC power supply and your tester as a trigger source.

[60dgrzbelow0]

If anyone is interested... The hardest component to find on the list of necessary parts for this project is the cast aluminum fuel rail-manifold unit ...but I just spotted an identical rail assembly I used here, which includes the full set of 2.8L-3.1L fuel injectors and the wiring harness to boot on eBay under the link listed below for a "Buy Now" price of under $10.00 + $5.00 for S&H. I want to give anyone else interested in monkeying around with this build a chance to snag it before I do for the peanuts the owner is asking for the unit, including extras... So here you go:

http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWAX%3AIT

Sorry... but I read the fine print that stated this sale included the EFIs for the 93' 3.4l Engine...and now that my machine has found out that two of the six in the set I just tested are either marginal or just bad... I had to buy these to run them all through this device and try to make a complete set for my son's 95 3.4L Re-Build. However... I went back to eBay and did another search and found this comparable fuel rail/manifold w/ a full set on injectors and the wiring harness for a bit more $$$. ( Sorry about that......)

Here is the other one...

http://cgi.ebay.com/ebaymotors/ws/eB...=STRK:MEWAX:IT

[60dgrzbelow0]

Nice contraption you have there. It does what you wanted it to do and that is what counts. You probably are saving $12 per Injector by cleansing them yourself. Def. will add up over time!

Thanks!... and the cool part is that I can do the cleaning of my EFI Sets any time I want and not have to wait on some company to do the job and then have to wait for them to get back to me and on the engine(s) with any hassles of shipping, too!