Nice work, very straightforward explanation of how these fuel systems work. I cannot tell you how many times I've seen that recirculation system plugged up because instead of fixing a leaky hose somebody decided to just delete it. I love these old IDI international motors, they are so robust, and if taking care of will literally run forever!
Very, very useful information. And you are correct in that information on the idi is difficult to find. Everything defaults to power stroke. Keep sharing your discoveries. And thank you for NAMING all of the components along the way!
This was very informative. I got a free vehicle with a 7.3 IDI and someone has cut and spliced everything and I don't know what goes to what or what was deleted that should not have been. This is the first video I have found that talks about what it supposed to look like before someone gets in there and starts modifying it.
Thank you , I just picked up a 96 F350 , and it also has been butchered , This helped alot . The fuel bowl filter was yellow , saturated with water , lots of cut wires . etc
Great video; posterity would GREATLY appreciate similar content for other engine bay components. Explaining all the hookups for a component makes diagnostics and repairs much easier to understand. Even a basic "this is X component, it does Y" overview of the major engine components would be very helpful. Very few 'anatomy' diagrams out there that I can find. Maybe then I'd be able to figure out what the dozen orphaned electrical connectors or capped vacuum lines in my truck originally did. Perhaps the filter head on my 85 has been replaced, since it lacks all those wires, and only has a single inlet, outlet, and Schrader valve. No provision for a return fitting, and the front/passenger/Cyl1 return line is plumbed to that tiny nipple on the filter head outlet. No return connection or tee on the front/driver/Cyl2 return rail on the opposite side of the bay. Also, the filter itself is the simple can type that doesn't have a water drain or end cap of any sort (though I still have a dash light for water, somehow). If the 5psi supply to the booster pump is higher than the return pressure (near ambient if it terminates at the tank), then fuel will flow through that tiny nipple to the tank. The small nipple size/orifice restricts this flow, effectively bleeding a small volume from the filter output, at the 12:00 position that air will tend to collect. Seems like my setup is more primitive than yours, while functioning the same (with fewer features).
Glad it helped somebody. If somebody had a modern Powerstroke that was busted willing to donate the entire truck I would do the same exact thing to help people by making more videos. You're definitely right about that friend that's why my videos are not that popular no one has old trucks anymore really.
Really? That's actually very rare in my opinion. Really the only place you ever hear of them anymore other than 3/4 tons and one tons are uhauls and old school buses! Badass, is it lifted?
Funny you mention that, I was actually at the junkyard working on another video that I actually threw out because it was a fail. When the guy pulling the front end off of this excursion was something heavy duty. Food for thought maybe hit up the junkyard? But yeah, everyone says Dana 60 is the way to go for the front
Hey Mr. Chaos You did a great job explaining all that so that tells me you are the man to ask questions to . LOL I Just bought a 1990 F350 crew cab 7.3 It's easier for me to just say every thing is wrong with it. LOL It set for about 10 years or longer I had it running and it was running good. Then the weather got cold and it wouldn't start any more. Glow plugs not working and air leak up top some place. Plugs melted and on and on. But if you go to 8:20 on your video and pause it you will see a little black square thing right in line with the spring on the accelerator. About the size of a relay. it has 2 black wires and 2 red wires going to it. Mine is melted and I have no idea what it's called to try and buy a new on , It's so much easier when you know what it's called. If you can help me with this I would appreciate it.
Hello thank you so much for commenting I enjoy talking with my viewers related to this. The little black box that is on top of the cable factory is essentially the guard for the cable itself mine broke off and I do not need it to run. The other black box that is about the size of a baseball but a square or cube factory mounts on the back side of the engine. I couldn't discern if you saw my relay off to the side, my engine is not factory in somebody rewired it and change the location but it functions exactly the same. This is called the glow plug relay assuming you're talking about the relay looking thing. I have one video that's more directed toward the area where the IP pump is and talks more about it. I will post the IP pump one right below and I will respond with a second video for the one that's about glow plug operation. Glow plug circuit on these old IDI engines are very finicky one glow plug that went bad can cause the whole thing in regards to starting cause issues. I'll gladly the respond if you have any more information best of luck! (Injection pump IP for short) ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-0JoqrQSllsw.html
Okay and here is this other video in regards to the relay looking thing known as the glow plug controller does exactly what it's called. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-rxQiTHhsH0E.html Best of luck!
@@ChaosExplained No it's not the glow plug relay. It's up front between the fuel filter and the injector pump. straght in line with the spring at 8:20 on your video. About 1 inch square black plug that dead ends . when I un plug mine it has 4 pins in a line. I looked on rockauto and it had 3 pins they called it a control module. But mine is melted and it has a very small circuit board in it. I don't know the purpose of it. mine has 2 red wires and 2 black. thank for your help.
Hey friend it does ring a bell actually it's been several months since then, I remember seeing it give me just a little bit and I'll look under the hood and I'll see if I can't be of some help. Talk soon bud
Ford actually has a tsb to remove the return to the filter head. It would normally have a small orifice fitting normally. But it will also cause your filter to drain out if you have a problem with the injector returns. Plenty of info on these trucks if you know where to look.
I assumed if you capped off the return line it would build pressure and leak or blow the lines off. We are talking about the small return lines coming off each injector, correct?
Lad to have found your video, about to tear into my new to me '85 F250 6.9l IDI I know it's been tinkered with pretty heavily and I want to put it back to as close to factory as possible.
Hi thanks for the video , one question if you already change fuel filter what can be the reason of fuel filter light on when you are in a hill its turn off when you stops a little bit. Sometimes it flashes thanks in advance..
@gerardoroiz6449 Without looking at the electrical diagram it's hard to honestly tell you. That light is basically coming on because it's telling us the fuel filter is clogged or needs to be drained of water. When is light comes on you should be able to feel an intense engine hesitation there are several causes for this. One could be of a pinched or damaged fuel supply or clog in the line most likely the filter. Best of luck
Ive got an 88 f350 7.3idi and my fuel filter light just started coming on when i go over 2k rpms or more. Changed out my fuel filter, cleaned my facet lift pump and still the light comes on and off. Truck runs perfect. Im thinking its that fuel filter vacuum indicator switch that you had explained in this video. Mine could be going bad.
@alpinehs the fuel returns to the tank as a return. Their are two fuel pumps. One is about 5 psi mounted on the side of the engine. The other is the high pressure pump that sits in the valley of the engine with many lines coming out. What is the symptom your having?
The square plug down line the harness past thewater in fuel sensor do you have any info on this? On mine it's another hacked one I'm trying to restore and have no idea what it was meant for mine is just filled with possibly epoxy.
That fitting for the recirculation on the filter housing has a very small pin hole size just so you know, I still have mine , That's how I know , I actually don't think it matters due to the unused fuel is free flow back to the tank , I deleted the mechanical pump & use an electric pump, Most diesel sites are encouraging that plugged off as yours is , But with that they are trying to sell their on the frame rail fuel filter systems. Anyway way if you didn't know that about that recirculation fitting having just a pin hole at the tip , now you do, I do think if a person was to put a regular wide open hose fitting there it would definitely cause a problem . Good luck .
The small orifice is there to bleed air from the filter, also bleeds air i any is sucked from a low fuel level in the tank -- The fuel that is returned is only a small amount, along with any excess fuel leaked from the injectors -- this also helps warm the fuel in the tank in cold weather -- the return orifice would be beneficial even with an electric pump
If you have cranked over the engine minimum of 5 Seconds I'd say and you go to the inlet line for the injection pump and you crack it loose and nothing comes out, then your mechanical mounted fuel pump that goes on the side of the engine block is the next culprit to check. oftentimes the diaphragms rip on the inside due to age and it is no longer able to pull a vacuum from the inside of the tank to create that little bit of pressure to the IP pump
@@ChaosExplained a friend pointed out that the rubber seal might not let that leak unless you unhook it all the way. I did that and got fuel. I have to wait until tomorrow to do anything else. Thank you. I wish I had a video explaining the internals of the filter head though. I have so many questions
Great video. However, using gas luke thatis insane. That is enough fuel to engolf your entire engine bay. I didnxt see you with a fire extinguisher near by.
