After I read this I tried it, it made no difference, Thanks for mentioning it though...one day I will figure this out and probly s^&t myself to death over the excitement of figurin it out
Glow plug troubles
- Thread starter Jay Krout
- Start date
Worth a shot,
If you're anything like me you'll finally get it and it will end up being something stupid simple that you'll kick yourself for.
I was troubleshooting mine, had proper voltage and everything. Ended up replacing the relay and running a manual switch, all before I found the nut at the battery that connects the glow plug feed wire had loosened up. I was furious I hadn't caught it sooner. I was getting juice, just not enough amperage though it.
OH yeah...Im quite sure it will be somethin stupid and simple.
Last winter I had some trouble with my welder, the alternator took a crap, so I got a new one and while I was at NAPA I picked up a new ground cable for the battery....well the motor would crank like crazy but wouldnt light up, it turned out the fuel shutoff solenoid wasnt opening up when cranking, got on the phone with Miller and with a industrial diesel dealer down in Harrisburg, he talked me through the process of testing the wires and couldnt find anything wrong so he sent me a new solenoid. Meanwhile I could pull up the lever on the solenoid it would start and I could weld all day long to shut it off I just pushed it down and turned the ignition switch off.
So sunday afternoon this new solenoid arrives and I put it on...it still wont light up....now I am gettin mad like a grizzly bear with a toothache... so I set down and think...whats goin on here. The only thing I did different electricly was that new ground wire. So I put the old one back on, sure as your born that thing lit right up. Turns out the original ground strap bein as how its braided carries the juice better than a ground cable.
I told Joe the guy Im contracted to about this and his eyes light up...this might be whats wrong with my loader he says. So he goes to CAT down the road from his shop gets the braided ground strap, has the young fella put it on and the old girl lights up like a brand new machine
I've heard stories about that before. I can't possibly understand how that makes a difference. But apparently it does. Makes no sense to me though.
The only reason I changed that ground strap to a cable was that the strap had some burrs on it and evry time I reached in there to do somethin I would get my hands caught on them.
After I changed it back to what it was original I was tellin that ol fella in the wheelchair about it and he said that they use the braided straps on equipment because of the juice they require to get these diesels goin. It aint a big diesel in this welder, its a 3 cylinder Deutz and they want a 650 cranking amps battery for it, which I guess is a pretty big battery for a little motor like this. Somethin else he told me was that the current goes from the ground to the hot, which is why the ground strap on this is actually a bit heavier than the positive cable. Im not so sure I understand it but he knows more than I do. I corrected the burrs by wrapping a piece of old air hose around and no more burrs to mess up my delicate mitts...after all I got an image to project ya know. Yeah right my mitts look like to 2 pieces of raw meat scrubbed with sandpaper, WD40, coal dirt and grease
Now I have a spare fuel solenoid just in case which dont bother me a bit...as long as I can find it if and when I need it...one of them things I know its here somewhere but where?
After I changed it back to what it was original I was tellin that ol fella in the wheelchair about it and he said that they use the braided straps on equipment because of the juice they require to get these diesels goin. It aint a big diesel in this welder, its a 3 cylinder Deutz and they want a 650 cranking amps battery for it, which I guess is a pretty big battery for a little motor like this. Somethin else he told me was that the current goes from the ground to the hot, which is why the ground strap on this is actually a bit heavier than the positive cable. Im not so sure I understand it but he knows more than I do. I corrected the burrs by wrapping a piece of old air hose around and no more burrs to mess up my delicate mitts...after all I got an image to project ya know. Yeah right my mitts look like to 2 pieces of raw meat scrubbed with sandpaper, WD40, coal dirt and grease
Now I have a spare fuel solenoid just in case which dont bother me a bit...as long as I can find it if and when I need it...one of them things I know its here somewhere but where?
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Big Bart
Tow&Slow
Jay,
I wish we all lived in the same town, at this point a couple of us would just come over to help you.
Ok some more thoughts.
You said -
12.1 volts from the ignition terminal to the ground on the controller.
That is a concern, you seem to have lost .5 or .6 volts, that is a classic voltage drop. Usually a drop of that much or more suggests there is a wiring problem. (Bad connector, bad wire, bad switch, corrosion, loose connector, etc.) If I read your statement correct, this is the wire that supply's power when you turn the key. If so try two things. 1) What happens if you just put a jumper wire from the positive side of battery to that post on the glow plug controller. (Give it a full 12.6 volts.) Does the controller work correctly? (The controller is sensitive to voltage.) 2) What happens when connected normally and someone else turns on the key to on, does the voltage drop any more? My concern is by the time you get out of the truck, walk around, and look at the voltage gauge the controller has shut off. So you see 12.1 volts but maybe when it was running for that 1-2 seconds it was even less. (Voltage drops generally are their worst when they are supplying power/loaded.) This would be a potential cause for the controller to not work correctly.
Second to your point, putting in new glow plug wiring harnesses takes out a lot of guess work. So if the above does not result in anything, I would replace them.
I know you said you had a falling out with Classic Diesel Designs, but in this case from what I have seen they offer the cleanest offering. So you can avoid them, but you may be bitting off your nose to spite your face. Most everything else I have seen offered is partial wiring with crimped connectors. Since this system is resistance sensitive, these are just crimp connectors, that leaves a lot of potential down the road for more issues. You can buy the IH harness but it is a little different and has some other wires in it, you just don't use them.
I did see this on e-bay, but I don't know anything about it. But it looks like a decent build quality.
Sorry this is still haunting you, stay on it, you will fix it. Plus you will be much better at fixing the glow plug system down the road when something else is going on. I get the impression like all of us, you like your truck, and it will be around for a while!
I wish we all lived in the same town, at this point a couple of us would just come over to help you.
Ok some more thoughts.
You said -
12.1 volts from the ignition terminal to the ground on the controller.
That is a concern, you seem to have lost .5 or .6 volts, that is a classic voltage drop. Usually a drop of that much or more suggests there is a wiring problem. (Bad connector, bad wire, bad switch, corrosion, loose connector, etc.) If I read your statement correct, this is the wire that supply's power when you turn the key. If so try two things. 1) What happens if you just put a jumper wire from the positive side of battery to that post on the glow plug controller. (Give it a full 12.6 volts.) Does the controller work correctly? (The controller is sensitive to voltage.) 2) What happens when connected normally and someone else turns on the key to on, does the voltage drop any more? My concern is by the time you get out of the truck, walk around, and look at the voltage gauge the controller has shut off. So you see 12.1 volts but maybe when it was running for that 1-2 seconds it was even less. (Voltage drops generally are their worst when they are supplying power/loaded.) This would be a potential cause for the controller to not work correctly.
Second to your point, putting in new glow plug wiring harnesses takes out a lot of guess work. So if the above does not result in anything, I would replace them.
I know you said you had a falling out with Classic Diesel Designs, but in this case from what I have seen they offer the cleanest offering. So you can avoid them, but you may be bitting off your nose to spite your face. Most everything else I have seen offered is partial wiring with crimped connectors. Since this system is resistance sensitive, these are just crimp connectors, that leaves a lot of potential down the road for more issues. You can buy the IH harness but it is a little different and has some other wires in it, you just don't use them.
I did see this on e-bay, but I don't know anything about it. But it looks like a decent build quality.
7.3 idi non turbo glow plug harness | eBay
<p dir="ltr" style="margin-top:0; margin-bottom:0; text-align:start;">7.3 idi glow plug harness. Condition is "New". Shipped with USPS Parcel Select Ground.</p> <br> <p dir="ltr" style="margin-top:0; margin-bottom:0; text-align:start;">This harness is for non turbo models. We also have one for...
www.ebay.com
Sorry this is still haunting you, stay on it, you will fix it. Plus you will be much better at fixing the glow plug system down the road when something else is going on. I get the impression like all of us, you like your truck, and it will be around for a while!
According to this checklist Jimbo (the old fella in the wheelchair) gave me along with the wiring diagram if it shows less than 8 volts then you are supposed to repair the fusible link (another thing I dont know much about), repair the wiring or replace the batteries, whatever it turns out to be the problem, so I think there is enough juice goin to that but if I get the chance I will do that tomorrow or sometime this week. My wife was workin the key for me through most of this stuff the past few weeks and for all of it today, she is pretty good about it and has more patience than I do. The reading I got was right after she turned the key. Jimbo would rather see me fix this right as well, he told me about some folks that bypassed the system and really messed stuff up not wiring it proper and I do know of one that caught fire and burnt the truck up completely.
I really dont understand why Ford had to make such a mixed up mess with this, why not just put a button there to push and let it off after 8 seconds. Seems pretty damn simple to me.
I like the looks of that harness, I gotta call that young lady back at Conestoga and see what she came up with, she said they was gonna be real busy settin up their new shop down there. I know Classic Diesel is a good outfit, and I guess I am the one in a million that the goose s%$t fell on last year, but I got other sources to look into as well. Or I might just make my own on a rainy day and put it in on a weekend, but I gotta go get the wire and the connectors for it first. Those connectors werent easy to find.
Good Lord dont tell me Im gonna have to fix it again down the road, I got no more hair on my head to pull out. Yeah I like my truck and all the goodies thats on it. It dont have to go fast it just gotta get me there and back evry day. I know it aint no racehorse its a workhorse and for the most part it does what I ask of it, so yeah it will be with me til they find me out there when I made my last weld on a dragline bucket or somethin
Thank you
I really dont understand why Ford had to make such a mixed up mess with this, why not just put a button there to push and let it off after 8 seconds. Seems pretty damn simple to me.
I like the looks of that harness, I gotta call that young lady back at Conestoga and see what she came up with, she said they was gonna be real busy settin up their new shop down there. I know Classic Diesel is a good outfit, and I guess I am the one in a million that the goose s%$t fell on last year, but I got other sources to look into as well. Or I might just make my own on a rainy day and put it in on a weekend, but I gotta go get the wire and the connectors for it first. Those connectors werent easy to find.
Good Lord dont tell me Im gonna have to fix it again down the road, I got no more hair on my head to pull out. Yeah I like my truck and all the goodies thats on it. It dont have to go fast it just gotta get me there and back evry day. I know it aint no racehorse its a workhorse and for the most part it does what I ask of it, so yeah it will be with me til they find me out there when I made my last weld on a dragline bucket or somethin
Thank you
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Its rainin like I gotta weld an ark together just in case and looks like it will be most of the day, yesterdays adventure with my knee left me with a very messed up knee and I dont feel like gettin soaked to the bone out there today. Gettin old sucks.
So I think I run to Minersville today and see if I can get the wire and the connectors and some of that heat shrink tape and make a new harness again and keep this one separate and by itself instead of buried in with the rest of the wires in that harness.
Its a good rain day project.
Thank you for your help
Popeye
So I think I run to Minersville today and see if I can get the wire and the connectors and some of that heat shrink tape and make a new harness again and keep this one separate and by itself instead of buried in with the rest of the wires in that harness.
Its a good rain day project.
Thank you for your help
Popeye
IDIBRONCO
IDIBRONCO
I think that people are mostly talking about a poor connection not letting enough amps go by, not voltage. You can read 12 something volts (or light a test light) even if there's only one strand of wire left in a bad spot in the wires. This will let very little amperage go by it. If you're getting much of a voltage drop, just think of the amperage drop that occurs between the two contact points of the test. The glow plugs only need (roughly) 12 volts in order to work correctly, but they need many times more amps to do the same thing.
I believe that it was an International thing rather than a Ford thing. The biggest difference between now and then, in my opinion, is technology/knowledge. When these glow plug systems were designed 35+ years ago, the level of technology and the amount of experience/knowledge of these systems was not even comparable to what is out there today. Just look at the difference between a state of the art truck today and then compare it to what was state of the art back then. Plus you're talking about engineers. All they know is what looks good on paper. What looks good on paper, and works adequately when everything is new, doesn't always work very well in the real world.
This do seem simple on the surface and would be a good idea if everybody out there had the same knowledge and patience that most of us on here do. The problem is that people (as a whole) are stupid and impatient. Most people today get upset if their car/truck can't understand them when they talk to it. They don't want to take the time to even manually input GPS addresses. There's very few glow plug systems that would hold up to the average citizen so I think that an automatic glow plug system is the best way to go for mass production.
I ordered that wiring harness this morning should be here by next weekend or early next week, just in case I ordered another controller and relay setup, still cant imagine that I got 2 of them in a row thats is bad but geese like to crap on my head and that would be my luck, its the one from Ford and is a good price. Havent got the chance to tinker with this at all this week, been workin some long days as usual and this weekend my grandsons are playin in a baseball tournament that if they keep winning they will go to the Little League world series, got to watch this, the one boy drove a line drive that hit the top of the fence rail yesterday. He got a double out of it.
I didnt get the chance to do this with the wire from the battery to the ignition post on the controller relay, maybe tonight after this ballgame i will get to do it. Got some questionsJay,
I wish we all lived in the same town, at this point a couple of us would just come over to help you.
Ok some more thoughts.
You said -
12.1 volts from the ignition terminal to the ground on the controller.
That is a concern, you seem to have lost .5 or .6 volts, that is a classic voltage drop. Usually a drop of that much or more suggests there is a wiring problem. (Bad connector, bad wire, bad switch, corrosion, loose connector, etc.) If I read your statement correct, this is the wire that supply's power when you turn the key. If so try two things. 1) What happens if you just put a jumper wire from the positive side of battery to that post on the glow plug controller. (Give it a full 12.6 volts.) Does the controller work correctly? (The controller is sensitive to voltage.) 2) What happens when connected normally and someone else turns on the key to on, does the voltage drop any more? My concern is by the time you get out of the truck, walk around, and look at the voltage gauge the controller has shut off. So you see 12.1 volts but maybe when it was running for that 1-2 seconds it was even less. (Voltage drops generally are their worst when they are supplying power/loaded.) This would be a potential cause for the controller to not work correctly.
Second to your point, putting in new glow plug wiring harnesses takes out a lot of guess work. So if the above does not result in anything, I would replace them.
I know you said you had a falling out with Classic Diesel Designs, but in this case from what I have seen they offer the cleanest offering. So you can avoid them, but you may be bitting off your nose to spite your face. Most everything else I have seen offered is partial wiring with crimped connectors. Since this system is resistance sensitive, these are just crimp connectors, that leaves a lot of potential down the road for more issues. You can buy the IH harness but it is a little different and has some other wires in it, you just don't use them.
I did see this on e-bay, but I don't know anything about it. But it looks like a decent build quality.
7.3 idi non turbo glow plug harness | eBay
<p dir="ltr" style="margin-top:0; margin-bottom:0; text-align:start;">7.3 idi glow plug harness. Condition is "New". Shipped with USPS Parcel Select Ground.</p> <br> <p dir="ltr" style="margin-top:0; margin-bottom:0; text-align:start;">This harness is for non turbo models. We also have one for...www.ebay.com
Sorry this is still haunting you, stay on it, you will fix it. Plus you will be much better at fixing the glow plug system down the road when something else is going on. I get the impression like all of us, you like your truck, and it will be around for a while!
#1 - Should i disconnect the wire on that post on the relay when I do this?
#2 - If it shows that makes it work is it safe to let it there til I can track down that wire in the harness?
Thank you very much,
Popeye
Big Bart
Tow&Slow
Jay,
1) Unhook it just in case it is grounding out somewhere, it may cause a voltage drop if you leave it on and add power with a second wire. Make sure your ignition is in the “on/run position” when you add the power to that terminal.
2) Yes if adding 12v from the battery the glow plugs then worked for say 5-15 seconds before going out, it would be safe to say that wire is not supplying power correctly to the controller. You then would trace it back to see why. Blown fuse, short or cut in wire, bad connector, etc.
Something else came to mind. Test the voltage at the connector that the glow plug harnesses hooks to when you do the above. Just in case your glow plug light in the truck is not working. You said it goes on for 1 second, so as I recall it works. But a better test is how long the glow plug harness gets power for. (It should be the same amount of time as the light in the truck.)
If that does not change anything, then it would appear your harness and/or your controller are causing the issue.(Don’t count out both are bad.)
Let us know how it goes.
1) Unhook it just in case it is grounding out somewhere, it may cause a voltage drop if you leave it on and add power with a second wire. Make sure your ignition is in the “on/run position” when you add the power to that terminal.
2) Yes if adding 12v from the battery the glow plugs then worked for say 5-15 seconds before going out, it would be safe to say that wire is not supplying power correctly to the controller. You then would trace it back to see why. Blown fuse, short or cut in wire, bad connector, etc.
Something else came to mind. Test the voltage at the connector that the glow plug harnesses hooks to when you do the above. Just in case your glow plug light in the truck is not working. You said it goes on for 1 second, so as I recall it works. But a better test is how long the glow plug harness gets power for. (It should be the same amount of time as the light in the truck.)
If that does not change anything, then it would appear your harness and/or your controller are causing the issue.(Don’t count out both are bad.)
Let us know how it goes.
Big Bart
Tow&Slow
You mentioned you are not familure with fusible links. These look like a standard wire but part or all of the wire has a specific melting point. (Just like a fuse does.) So if it is a 30amp fusible link it will allow that much amperage through it. But if you try to pull/push say 50 amps it burns the wires inside and that breaks/stops the connection.
The problem is looking at a fusible link you may not know it is no longer conducting power. (Unlike a fuse the is no little window to look into.) You have to test it to see if it still is passing power. They used them on the glow plug controller and the alternator charge wire. At least in 1988 they did. So above someone mention to test that they are working. (As I recall they used two fusible link wires instead of one big one.) So in theory if one is bad it could cause the controller to get a lack of voltage and perhaps turn off. If both are bad you would not be getting 12v to the relay and thus when it energizes it would not be giving 12v to the glow plugs.
So you would be trying to test if both fusible links have 12 v at the relay. But as I recall they may share a single connector. So to test you will need to separate and test each one.
The problem is looking at a fusible link you may not know it is no longer conducting power. (Unlike a fuse the is no little window to look into.) You have to test it to see if it still is passing power. They used them on the glow plug controller and the alternator charge wire. At least in 1988 they did. So above someone mention to test that they are working. (As I recall they used two fusible link wires instead of one big one.) So in theory if one is bad it could cause the controller to get a lack of voltage and perhaps turn off. If both are bad you would not be getting 12v to the relay and thus when it energizes it would not be giving 12v to the glow plugs.
So you would be trying to test if both fusible links have 12 v at the relay. But as I recall they may share a single connector. So to test you will need to separate and test each one.
I ran a wire from the positive post on the battery to the ignition post on the relay, when I hooked the neg terminal up on the battery the relay started clicking, didnt even nhave the key in the ignition, I put it on the starter relay it did the same thing, so I disconnected it.
The 2 supply wires to the relay do not have the same connector each has its own eye, and one is hot and one is not...Jimbo told me thats the way it is supposed to be.
The new wire harness should be here on Tuesday or Wendsday, I will run new wires to the controller then and replace the harness to the glow plugs, and if it still dont work I will put the new relay and controller in that I bought, but I still cant believe evry one of these controller and relays I hsve are no good, some arent even 2 months old.
If that dont fix it then the hell with it I will figure out how to wire the thing with the push button switch Ive got here. Im tired of messin around with this stuff its time to move on
The 2 supply wires to the relay do not have the same connector each has its own eye, and one is hot and one is not...Jimbo told me thats the way it is supposed to be.
The new wire harness should be here on Tuesday or Wendsday, I will run new wires to the controller then and replace the harness to the glow plugs, and if it still dont work I will put the new relay and controller in that I bought, but I still cant believe evry one of these controller and relays I hsve are no good, some arent even 2 months old.
If that dont fix it then the hell with it I will figure out how to wire the thing with the push button switch Ive got here. Im tired of messin around with this stuff its time to move on
Big Bart
Tow&Slow
Thanks for the update. I am sure you will figure it out. You now know the glow plug controller is not happy about the resistance and goes immediately into on off mode. Thus will not heat the glow plugs properly. So the controller, glow plugs, or wiring harnesses have an issue.
I have not tested before, so Jimbo might be right. I would guess they would not run two hot wires the gp relay unless they both would carry power. Would a member who has experience let Jay know if both fusible links to the gp relay should be hot? Jay I wonder if Jimbo is wrong if this is complicating things. Causing high amps and putting a strain on the system. Let’s see what others say.
Jay I get it, if new glow plugs, relay, and wiring harness don’t solve your issue then the heck with it.
I have not tested before, so Jimbo might be right. I would guess they would not run two hot wires the gp relay unless they both would carry power. Would a member who has experience let Jay know if both fusible links to the gp relay should be hot? Jay I wonder if Jimbo is wrong if this is complicating things. Causing high amps and putting a strain on the system. Let’s see what others say.
Jay I get it, if new glow plugs, relay, and wiring harness don’t solve your issue then the heck with it.
