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Discussion Starter #1
I am in the final stages of my motor swap of a 7.3 idi with hypermax turbo into a 73 Ford Highboy. This is my second 7.3 I've put in, my last had bad head gaskets and as a 16 year old I decided to get another rather than tackling that right now. This motor supposedly was rebuilt recently and should be ready to go. I replaced the glow plugs right away because I had new motorcraft ones on hand. I had the motor coughing to life but now won't fire at all, even if I unhook the glow plugs and try to give it a little nose candy ((either), ik it's not good stuff) but it won't even cough with that. In my experience that should bypass any fuel/air in the fuel issues. Leading me to think the timing was off, I can look on the pump to timing cover and the marks line up, so before I go thru the pain staking task of assuring that the guy who rebuilt it didn't get the pump drive gear a tooth off of the cam, I wanted to see if you guys knew of any other possibilities as to what is going on. I also replaced the leak-prone return line caps and noticed that when I blew back into the return line system there was a ton of resistance, and when I unhooked the return line that goes into the IP fuel sprayed out (it was pressurized). Could a clogged return line cause a no start because of a fuel issue? Just grasping at straws here I am unfortunately lost right now. I was considering replacing the IP with a spare one I have laying around that I know works, but figured I'd ask for help before I do that too. Any help is appreciated!
 

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With ether into the intake, it should lock the engine up (why it isn't a good thing), a lot like seriously advanced timing on a gas engine (the old kind with a distributor). If that isn't happening, then something is restricting the air flow into the engine, or it has lost all of its compression somehow. Did you get all of the shipping caps/rags out of the intake system? I know that sounds like a smart-ass question, but stranger things have happened. It isn't very likely that a freshly rebuilt engine would suddenly loose all of its compression. I have seen some (natural gas fired) engines refuse to start with a plugged exhaust, shipping cap on the muffler outlet. That engine doesn't have a lot of pull at the intake until it starts running, so it wouldn't take much to stop it from getting air.
You can also take the return line loose where it goes to the tank, and run it off into a bucket to see if that is the trouble. Try cracking the injector lines a little at the injectors and see if there is fuel coming out. Ether should have bypassed all of that though.
 

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Discussion Starter #3
I just meant that as a rule of thumb ether isn't the best choice to get something started but it kindof locks up yea, but it still cranks after , as for the rags on the intake system I have no clue. I bought the motor from a neighbor who had bought it rebuilt from the last guy, it was supposed to have been running in the Jeep truck that he bought it in. But he has a bad memory.... So if rags were still there, what am I in for... Is it trashed now?
 

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If that engine is locking up like you just described, then the air is getting into the cylinders. I have never been successful at getting one of these engines to start using ether for that very reason. I always get scared of breaking pistons before it actually starts. You probably just need to get the fuel system working. Pull the return line loose from the back of the engine where it runs to the tank, and run it into a 5 gallon bucket. Then crack the injector lines at the injectors, and crank the engine 30 seconds on the starter, 60 seconds rest until you see fuel at the injectors. tighten everything back up, and see if it starts. Are you sure it is getting fuel at the filter? Check that by holding the schrader valve open while cranking the engine (assuming you have the filter assembly that was on the original truck. Open the discharge side of the filter if you don't ). Is the fuel shut off valve working? with the ignition switch on, unplug the wires on the passenger side of the IP. You should hear an audible "click" that would be the solenoid valve closing, and opening. The pressure you described in the return system earlier doesn't sound normal, that's why I said to pull the return line off. You don't want a lot of pressure on the return. If you aren't sure about rags in the intake, now would be a very good time to check that out. Rags can do a lot of damage if they get into the turbo, or engine. If they're there they most likely haven't done anything yet, since you haven't had it running. Once you get it started, and know it runs, then hook your return back up, and see if it continues to run. If it does, good. If it doesn't then troubleshoot from the engine to the tank. If you have two tanks, make sure the switch valve works properly, and is hooked up properly. After that clean the line out. I usually use compressed air, and blow it out.
 

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Discussion Starter #5
If that engine is locking up like you just described, then the air is getting into the cylinders. I have never been successful at getting one of these engines to start using ether for that very reason. I always get scared of breaking pistons before it actually starts. You probably just need to get the fuel system working. Pull the return line loose from the back of the engine where it runs to the tank, and run it into a 5 gallon bucket. Then crack the injector lines at the injectors, and crank the engine 30 seconds on the starter, 60 seconds rest until you see fuel at the injectors. tighten everything back up, and see if it starts. Are you sure it is getting fuel at the filter? Check that by holding the schrader valve open while cranking the engine (assuming you have the filter assembly that was on the original truck. Open the discharge side of the filter if you don't ). Is the fuel shut off valve working? with the ignition switch on, unplug the wires on the passenger side of the IP. You should hear an audible "click" that would be the solenoid valve closing, and opening. The pressure you described in the return system earlier doesn't sound normal, that's why I said to pull the return line off. You don't want a lot of pressure on the return. If you aren't sure about rags in the intake, now would be a very good time to check that out. Rags can do a lot of damage if they get into the turbo, or engine. If they're there they most likely haven't done anything yet, since you haven't had it running. Once you get it started, and know it runs, then hook your return back up, and see if it continues to run. If it does, good. If it doesn't then troubleshoot from the engine to the tank. If you have two tanks, make sure the switch valve works properly, and is hooked up properly. After that clean the line out. I usually use compressed air, and blow it out.
I am getting fuel at both the shrader valve and I had the injectors bled, so I'm getting fuel there. But I did notice that when I turn my electric fuel pump on and hold the shrader valve it puffs air out every couple seconds
 

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Discussion Starter #6
If that engine is locking up like you just described, then the air is getting into the cylinders. I have never been successful at getting one of these engines to start using ether for that very reason. I always get scared of breaking pistons before it actually starts. You probably just need to get the fuel system working. Pull the return line loose from the back of the engine where it runs to the tank, and run it into a 5 gallon bucket. Then crack the injector lines at the injectors, and crank the engine 30 seconds on the starter, 60 seconds rest until you see fuel at the injectors. tighten everything back up, and see if it starts. Are you sure it is getting fuel at the filter? Check that by holding the schrader valve open while cranking the engine (assuming you have the filter assembly that was on the original truck. Open the discharge side of the filter if you don't ). Is the fuel shut off valve working? with the ignition switch on, unplug the wires on the passenger side of the IP. You should hear an audible "click" that would be the solenoid valve closing, and opening. The pressure you described in the return system earlier doesn't sound normal, that's why I said to pull the return line off. You don't want a lot of pressure on the return. If you aren't sure about rags in the intake, now would be a very good time to check that out. Rags can do a lot of damage if they get into the turbo, or engine. If they're there they most likely haven't done anything yet, since you haven't had it running. Once you get it started, and know it runs, then hook your return back up, and see if it continues to run. If it does, good. If it doesn't then troubleshoot from the engine to the tank. If you have two tanks, make sure the switch valve works properly, and is hooked up properly. After that clean the line out. I usually use compressed air, and blow it out.
But as for the rags, i pulled the obvious one that was in the intake side of the turbo and the exhaust side. Could there be more deeper in the motor, like would they have put them under the manifolds (both intake and exhaust)?
 

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I would seriously doubt it. I don't know anyone who would take something apart to stuff rags in it.
 

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Not necessarily. Are you sure there is fuel at the injectors? Are you sure the glow plugs are actually getting power to them? Check the simple stuff BEFORE you start tearing the front of the engine off to find that timing is perfectly OK. It is possible that timing is where you will find your trouble, but check the other stuff first, because it could just as easily, probably more likely be one of the simple things. The fact that it is kicking back like that when you put ether in it, means that the ether is getting into the cylinders. Diesel engines DON'T like to run with air in the fuel system. Get the air purged before you decide that timing is off. You said earlier that it would try to start, then it quit trying. Sounds to me like it was trying on what fuel there was before the air bubble hit it.
 
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