So, in a previous thread I asked for advice for a medium duty farm truck for my brother’s farm. He found a purchased and International 4700 with the T444E. Truck seems to be well maintained, started easily and ran great for the 3 hr drive home. I looked it over a day or two after he brought it to the farm, it was hesitant to start then and required multiple cranks to start (at the time we attributed it to cold weather). After it started, it ran smoothly and I drove it a bit. Nothing unusual driving, good power and ran smooth. After I parked it, the truck sat for a week or so before my brother tried starting it again. Now, it will not start. Truck cranks freely, battery and starter seem fine. Just a little light grayish smoke from the exhaust when cranking. He changed the fuel filter, cleaned the pre-strainer and put a gauge on the low pressure test port after the fuel filter. 40 psi on this port, which the manual indicates is normal. Thoughts on what to test next? I’m thinking the injector pump has air in it or the shut off solenoid is faulty. Thanks to @mekanik we have a service manual for this engine and will be working through the troubleshooting process.
Check your pre heat relay. See if your getting voltage out to the glow plugs
Interesting you mention this. According to the service records it’s been replaced once before, so clearly it was problematic at a previous time. We’ll add this to the list.
Common issue, you said you have smoke. Check the valve cover pass through, it will melt at the connections. Do you hear the "injector cackle"?
I don't know if IH uses a similar system but the Ford version had issues with the cam sensor. It sends a signal to the injectors on when to fire. Symptoms are similar to what you describe. Those of us who had the PowerStroke kept a spare in the glove box. It's located in the side of the timing cover and takes a 10mm wrench to replace.
I will expand a bit on Steve's comment: if your tach is moving while cranking, cam position sensor is ok. If truck has a block heater, plug it in overnight, and report back. Find the ICP(injector oil pressure switch) top of cylinder head, driver side, unplug it--computer will default to spec and start if switch is bad Very possibly injector fuel pressure regulator, located under fuel bowl top of engine I will find a pic of the engine with sensors marked and named and post up
Can we have a picture of the whole top of the engine? I'm not sure how similar that is to my Ford 7.3L but if it's the same, the first thing I do when I get a crank/no-start situation is remove the connector from the ICP (injection control pressure) sensor on the driver side head, and see if it starts that way. Edit-oops Jimbo beat me to it...
This might help also.
Thanks guys! I’ll get better engine pics up soon!
The only cackle I heard was from the chickens running around…. But, tell me more!
When ICP is high enough to actuate the injectors the purge or surge of oil combined with the solenoid actuating makes a distinct sound referred to as cackling. At least it was 30 years ago.
I can’t say I heard this, but I’ll listen for it next time I’m working on this truck. Thanks!
More pics of the engine: View attachment 1743592461613.jpeg View attachment 1743592633571.jpeg View attachment 1743592652044.jpeg
Main issues I ran into--ICP or wiring harness--which was a main connection at right valve cover for engine harness.
Let’s try this photo thing again:
This a 47 or 4900 chassis?
More:
4700 to my knowledge.
Unplug this sensor and see if it starts
What will that do? That's just the oil pressure sensor. That reservoir under that sensor better be full though.
You're right, I was wrong. I should have studied the picture more closely. On the Ford that sensor only has one wire. This is the ICP sensor on my 7.3. If you can find a similar sensor on the head or high pressure oil system, that would be the correct one to unplug. I believe it should have 3 wires going to it.
Are you generating a check engine light or flash codes?
Check engine light, yes. He has not pulled the flash codes yet. I will post those when I have them.
Autozone, O'Reilly's, etc have inexpensive code readers Post up the codes when you get them
Cheaper than that. Press cruise on and set for 10 seconds, the check engine light will flash out codes. Count the flashes, write em down until the sequence repeats itself.
Here is an overhead shot from the front; #13 is the ICP, unplug and see if it will fire
Interesting, did not know this trick I am afraid most 7.3s still on the road probably don't have functional cruise control anymore, especially two ton trucks
That was nearly all Crapistars with the introduction of electronic fuel management.
Not exactly your problem, but close. Fire dept has a similar vintage with a 466. Truck would start hard, and die at idle. We removed the fuel line at the tank fitting and pressurized the line. The bleed screw on the fuel filter under the passenger seat had cracked but still looked good (plastic fitting). We replaced it with a steel plug. It was a standard orb size fitting.
I had a few minutes to stop by and look at this truck today. I unplugged both the sensors circled below (one at a time) and no change- still no start. I think one of these is the right sensor? Glow plug relay clicks on when the “wait to start” light comes on during starting sequence. However, we noted that the relay gets very hot and only measured 10v across the terminals. So, we will get a new relay just the make sure that’s not the problem. Finally, the blink code was 5-4-3. I will research that in the manual, but does that give any other direction?
That preheat relay looks like the hot side has been loose for a while. The discoloration gives it away. The bigger question is, is the power getting to the plugs. Additionally, if the voltage drops below 9½ volts, it may not support the computers. no computers, no fire. Maybe we have a simple battery problem.
Yeah we will clean all that up with the new relay for sure.
I've had 4 calls for 7.3s not starting in the last 3 weeks, 3 were airbound and took a lot of cranking and cycling the pump to bleed out and 1 had a blown ignition fuse. If your voltage is the same on either side of glow plug relay the relay is working, the plugs draw my truck down to 11 or so volts when they're on. Another thing at least in the pickup chassis is that the glow plugs stay on a lot longer than the light, usually a minute and a half when it's stone cold. We wire lights off the hot side of the relay and trucks start a lot easier because you're not drawing the glow plug amps while trying to crank.
If just two glow plugs are faulty on a 7.3 it will cause a starting issue.
You'd be surprised, I have a 2000 f450 and with the glow plugs unhooked it'll still start in 40 degree weather
I'm glad for you--but it's not common.
Glow plugs, glow plug solenoid/relay, under-vavle-cover wiring harness/connector are all common problems I've had on 7.3 Fords, probably the IH's would be similar. All are things that just degrade with age/use and none are hard to fix.
Picked up a new glow plug solenoid today and IDM relay, it’s pissing down rain though, so further troubleshooting will have to wait. To be continued….
Well, apparently the rain didn’t dissuade my brother from putting the new glow plug solenoid in. And, it starts! Thanks to all the advice in this thread, it’s been helpful to have a reference for all the other possible trouble points with this engine.
I run 5 7.3s and have 5 more for parts, bound to have one solid one in the bunch