Diesel Fuel Injector Test

What's up everyone, welcome back to Workshop Rebuild. In today's video I'll be testing a mechanical diesel fuel injector. I will be testing it for the specified pressure, I will be testing it for a proper spray pattern, and I'll also be testing it under pressure for leakage. Off to the left of the screen I have a diesel fuel injector which is completely disassembled. I will share with you guys all the components that make up a diesel fuel injector, and I'll also share with you guys how one of these diesel injectors actually works. So if you guys are interested in that, stick around until the end. On this table I have my setup, right here we have the diesel fuel injector. We have a hard line which is then connected to our diesel injector tester. This is a hand-operated diesel injector tester. What it consists of is a diesel holding tank in the back. This will supply diesel fuel to our hand pump, that's why it's hand-operated. We will just push this down and it will create pressure and supply diesel fuel to our injector. Obviously our injector only opens up at a certain pressure because there is a spring in here, so we also have a gauge for that. This gauge shares with us the PSI rating or the MPA. We will be checking all our pressure ratings in PSI today because this diesel injector should open up at 2800 PSI. Off to the right we can also adjust our valve. This hand-operated valve will also increase or decrease our pressure as we like, so we can also use this to help out, and we'll also be using this for our leakage test. Right now I'm going to test this diesel fuel injector. Underneath I have a little drip tray in case you need to test multiple diesel fuel injectors. You want to loosen up that connector and you'll have a little bit of diesel fuel which will drip down, so I have a drip tray. To test this diesel fuel injector, not that it just sprays out into the air, I will be taking a bottle and I will put that onto the diesel injector just like that. Right now our rating is at zero. I'm going to hand tighten the valve just a little bit, something like that, and now I'm going to apply pressure and build up pressure within the system. You will see the gauge is already going up and it should open right now. As you guys saw, the diesel injector opened up. Now I'm going to share with you guys a close-up on the gauge and I'll also share with you guys a close-up on the spray pattern. I'm going to start pumping and you'll see it should open up at 2800 which is close to 3000 and we have the red markings on the outside perimeter of this gauge. So the pressure seems to be opening at just over 2800 psi and then it drops back down. So we have a good diesel fuel injector and now I'll share with you guys the spray pattern. On the tip of the diesel fuel injector we have the nozzle body, that is this part right here, and on the tip of the nozzle body we have four tiny holes. So I have to make sure that the diesel will spray out in four different directions and I also want to make sure that the spray pattern of those four different directions has the same amount of diesel fuel. I put the bottle back onto the fuel injector and we'll see if we have diesel coming out in four different directions. The diesel fuel injector seems to open up at 2800 psi which is good and the spray pattern in four different directions seems to be spot on. Now I can check the diesel fuel injector for leaks. To perform the leakage test I need to clean up the tip of the diesel fuel injector. I don't want to remove the bottle just yet, I want to make sure that the pressure has gone down all the way and then I can remove the bottle safely. Now I can take a clean rag and I can clean the tip of this diesel fuel injector. I want to make sure it's perfectly clean just like that and I'm going to install the bottle back onto the diesel fuel injector. Now I can raise the pressure on this system. The manual calls for 2500 psi, that's where I have to test the diesel fuel injector for leakage. So I will bring it just past 2500 and then we'll have to close off this hand valve. So the pressure right now is at 2700 psi and now when I go over to the diesel fuel injector you want to make sure that the tip of the valve body is perfectly dry. If you see a little drip underneath the valve body right in this area that means your diesel fuel injector is leaking. As you will see this one is still perfectly dry and our pressure is still up at 2700 psi. As you guys just saw I performed the pressure test, I performed the spray pattern test, and I also performed the leak test on the mechanical diesel fuel injector. If you guys have any questions or concerns leave a comment down below and if you guys thought this video was helpful to you I'd really appreciate it if you hit the like button down below. But right now I'm going to go ahead and share with you guys all the components of this diesel fuel injector and I'll also share with you guys a little bit of information on how it works. I have all the parts laid out on this table that make up this diesel fuel injector. I have the injector body, I have a spring, I have the spring seat, we have the separator plate, we have the valve nozzle and the valve body as well as the retaining nut which holds everything in place. You'll also see two index pins that will position the separator plate within this assembly. All these parts right here make up the diesel fuel injector. You'll notice that there aren't any shims. The shims would usually lie between the injector body and the spring. If we add more shims or a shim pack the spring will be under more tension that means the pressure of this injector pump will go up and if we take away shims or don't have any shims at all that means the pressure rating is very low. So this injector has been set up with no shims but it is still to spec so that means they did not have to add any shims. Now you guys will know what is inside a mechanical diesel fuel injector but I'll share with you guys how all this works. The easiest way to understand this assembly will be for me to put it back together and as I put it back together I will do some explaining. So this right here is the injector body and where the fuel comes in is on the top end and that is this end of the injector body. We have a tapered fit and our hard line will come right into that tapered fit and with the nut we will be able to tighten everything together and that will be sealed off. Now the fuel comes into this injector body right here and diverts off to the side and comes down off to the side. You will notice on the bottom end of this injector body there are two bigger bores which will accommodate our index pins and one of these bores is a little bit smaller which is this top bore right here and that's where the fuel will be coming out. This big bore that you see in the middle only goes a certain length down into this injector body stops somewhere here and we will be able to insert our shims, our spring and also our spring retainer which is on the very front. Within this system we also have a return which is through the middle and out off to the side. These two little ends are our return so if we have excess fuel that comes into the injector we will be able to have the return fuel going out back to our injection pump. Now the next thing I will be installing is the spring that will go down into there just like that. The next part I will need is the spring retainer that is this piece right here will be installed just like this. Now this will also center the spring properly and give it the proper tension. You also want to make sure that that piece is in good condition that the tip is not worn. If the tip is worn by any means you'll also have to add more shims in the back obviously. Now our retainer plate is this piece right here. You will notice that there are two sides of it and one side has a little bit of wear and that was towards the spring retainer so I'll put it back just like that. When we look at these two parts you will notice two bores are bigger and one is a little bit smaller and that's how it will be put back together just like that. Before I put this back together I will grab the two index pins and insert them into the two bigger bores just like that. So our fuel will be coming out of this tiny hole right here and these two index pins allow me to locate this separator plate just like that. Now I can continue with the assembly process. The next two parts I'll have a look at are the valve nozzle and the valve body. Now when we look at the valve nozzle specifically you will notice that there are three tapered ends on this pin. One is right there, one is right here, and one is at the very tip. These tapers will allow the nozzle to open up or push back onto the spring on this little end which acts as a little plunger up against the spring retainer. Now over here we also have the valve body and this nozzle valve will be inserted within the valve body just like this. It is a very tight and snug fit so you want to make sure that goes in very smooth and now what happens the fuel will get pushed through this little bore it will pass through through the tip and it will push on that taper upwards or back and this little plunger will then pop out not that much obviously but push up and out against that spring and now when there's enough force or pressure pushing down into this little bore the spring will let go and allow the tip of the valve nozzle which is this tip right here to open up and retract and the tip of the valve body has a couple tiny holes in it and that will give us an even spray within our combustion chamber. So I have a flashlight right here and I'll share with you guys those tiny little holes on the tip as you will see there's one right there and there's another one right there so there are a couple around the perimeter as you can see there's one right there and then I can even move it on to the next one there's another one right there so the fuel will be coming out of those tiny little holes on the tip of the valve body. Before you assemble all this you want to make sure that this is lubricated especially the tip of the valve nozzle once you put it in that everything is lubricated but if you push it in like that you can then align it with the two indexing pins just like that once it's held in place you can grab your retainer nut slide that on and tighten that all the way down just like that once your retaining nut is back on there you want to tighten it up and then you'll have a complete mechanical diesel fuel injector. So I shared with you guys how to test a mechanical diesel fuel injector I shared with you guys the disassembled state and I shared with you guys the assembly process of this diesel fuel injector but I also shared with you guys how one of these things works so if you guys thought this video was helpful I'd really appreciate if you hit the like button down below don't forget to hit that subscribe button and turn on your post notifications because then you'll always get notified once I upload a brand new video so with that said stay tuned for an upcoming video