There is nothing like a overnight cold start so that will be the test. 10 seconds of cranking is a lot. I would let the controller glow the plugs, crank it for 5 seconds, and then turn the key off and see if the controller will cycle the plugs again. That might give you more cumulative glow time and be easier on the starter.
Finally got around to testing, and then replacing the glow plugs.. 4 stuck.
- Thread starter MJGenay
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MJGenay
Full Access Member
Yeah I don't like the 10 seconds of cranking, I was right on the verge of giving up when it caught and kept going. I'm going to give it a bit before I go to start it, just in case I can find anything else that might be an issue. I'm getting tired of trying to figure this out as it is costing me a lot of time not working, but I am also not ready to give up on this. It seems like it should be pretty simple. 12V to relay/controller, once key is turned resistance starts to build, after 15ish seconds the resistance is high enough that the relay clicks off. Power is sent through the relay and through the harness to the plugs. It is 9V that is be sent to the plugs... does anyone know if that is correct or I am supposed to be getting 12 V?
Only other thing I can think of is I have insufficient compression because the engine is old. I have no idea the miles. Plugging the truck in for two hours it starts right up.
I'm going to try cycling the glow plugs before I crank it over. Something I've noticed is the Wait to Start stays on for about 15 seconds every time, even if I just turned the key off after the last cycle and turned it back on. It wasn't doing that before I replaced the plugs and I don't know if it should be doing that... my logic says no, it should be sufficiently warm after the first cycle.
Brian VT
Full Access Member
Have you tested the plugs? All the plugs need to have ohms close to being the same.
A "matching set", if you will.
A "matching set", if you will.
MJGenay
Full Access Member
I haven't, I just assumed new Beru's would be fine. I'll do that.
The_Josh_Bear
Full Access Member
9v to the plugs is correct only when they are "on", due to voltage drop from 200+ amps feeding the plugs. If you unhook the plugs it should read VERY close to battery voltage.
You should check the connector under the HVAC blower. You're looking for two black/orange stripe wires going in and two solid yellow wires coming out-- these are the power wires to the GP controller.
This connector melts because Ford was cheap, and you may have a corroded connector there hurting your amperage.
Unfortunately even Beru GP's are burning out a lot lately...could be knock-offs or bad quality control. So testing that all 8 are working is important. With one plug burned out, the controller will short-cycle.
How long is your WTS light on? Should be at least 10 seconds at those temps.
You should check the connector under the HVAC blower. You're looking for two black/orange stripe wires going in and two solid yellow wires coming out-- these are the power wires to the GP controller.
This connector melts because Ford was cheap, and you may have a corroded connector there hurting your amperage.
Unfortunately even Beru GP's are burning out a lot lately...could be knock-offs or bad quality control. So testing that all 8 are working is important. With one plug burned out, the controller will short-cycle.
How long is your WTS light on? Should be at least 10 seconds at those temps.
MJGenay
Full Access Member
I haven't had time to fool with the truck yet today. I will check that connector and check the glow plugs. Wait to Start light is on about 15 seconds. Seems consistent, whether it was just cycled or not.
WrenchWhore
Full Access Member
I've been following this thread and this was something I was going to suggest as well. Mine is pretty cooked as well causing some very noticeable heating of the wires going into the connector but not on the other side towards the glow plugs
WrenchWhore
Full Access Member
So instead of just pointing the finger to things and saying check this I decided to go outside and do some recon myself on my sh**box. I went outside and pulled apart the glow plugs harness connector and this is what I found...Not good. No trace of dielectric grease, full of dust and dirt, and you can see the green corrosion forming and spreading. The terminals on the bottom are the big gauge wires running the current. This looks like an area of interest to look at. I tried to start the truck without this connector hooked up and obviously it didn't start. I did notice after I plugged it back together with all this crap disturbed inside it started clicking like it had a bad glow plug. This truck has brand new Beru glow plugs and didn't do this before. Just goes to show that it doesn't take much to **** off this glow plug controller. Good luck.
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Olds64
Registered User
If it's going to drop into the single digits I'd use the GPs and the block heater. Especially if you're going to have it parked outside. Hope it starts easily for you tomorrow.
MJGenay
Full Access Member
So I got home an hour ago and tried something. I turned it on, let the wait to start light go out, and then left it on until the volt meter jumped and I heard the relay click... still no dice and it was 20 degrees. Put the block heater on and it started right up an hour later... just now. I'm going to go drive it a bit, to warm it up, I have some 5w40 in the garage and I think I'm going to drain the 15w40 and use that. Then I'm going to go check on that damn connector. Everything seems to be getting power, but maybe not ENOUGH power. I'm going to follow the wires back from the glow plug controller and see what I can find. I'm hoping its that connector.
The best thing to do with that connector is take the large wires and cut them very close to the connector. Just use the connector for all the smaller wires. With the large wires, connect them directly, bypassing the original connector.
You can get fancy and buy a decent connector that will hold the amperage, and connect the large supply wires to that. Or you can be cheap and simple like me, and just use 4 crimp ring terminals and then use two small bolts and nuts and bolt the wires together. I recommend you have some way to disconnect these wires, since the original connector feeds everything on top of the engine, and the wire runs over top the valve cover. It's very convenient to be able to disconnect these wires when changing valve cover gaskets, or pulling the engine, or any other serious engine work where the wires will be in the way.
You can get fancy and buy a decent connector that will hold the amperage, and connect the large supply wires to that. Or you can be cheap and simple like me, and just use 4 crimp ring terminals and then use two small bolts and nuts and bolt the wires together. I recommend you have some way to disconnect these wires, since the original connector feeds everything on top of the engine, and the wire runs over top the valve cover. It's very convenient to be able to disconnect these wires when changing valve cover gaskets, or pulling the engine, or any other serious engine work where the wires will be in the way.
MJGenay
Full Access Member
Okay so those wires were already cut and put together with crimp connectors, in fact every wire on that connector was - the connector was gone. One of the heavy wires crimp connector was partially melted (black/orange going yellow). I also found MORE fuse links over by that passenger battery... in fact I found one that had melted.
I kinda went for a temporary half assed fix on both. I just used some crimp connectors to reconnect the fusible link that had melted, and then I did the same for the melted crimp connector mentioned above. I wish I had seen your suggestion Franklin before I used those crimps... the nut and bolt system makes a lot of sense.
After turning the glow plugs on and walking over to that portion of the engine bay I could smell some "hot plastic" so to speak but the links all seemed to stay intact. I'm not sure if I have a short, or what. I'm kinda dreading soldering new fusible links in, I haven't soldered since I was a kid with a model train set...
Here is something different though, before, I would turn the key, WTS would stay on about 15 seconds, and then I would finally hear the glow plugs kick off after about another 30 seconds (this was earlier today). Just now, I heard the relay click off after about 15 seconds. Might be getting somewhere here. I don't think the relay/controller was getting enough power - it was getting enough volts, just not amps. Just a theory so far as I haven't bothered trying to start the engine as its still warm.
I can't thank y'all enough for the help you have provided thus far. Thank you.
WrenchWhore
Full Access Member
I can see what you mean. Even after I cleaned and blew out all the junk in the connector and dielectric greased it it still feels like the hot wires leading into the connector are still getting overly warm and not so much after the connector. Definitely some resistance through that circuit.
Soldering and shrink wrap is best, but you can use other methods to put the links in place. The weather and dirt is the biggest enemy. You can buy those cheap uninsulated metal butt connectors and crimp the fusible link in place and then slide shrink wrap over that. Or you can buy those fancy butt connectors that have the shrink wrap built in around them.
Fusible links are just undersized wire with special insulation around it that won't catch fire.
MJGenay
Full Access Member
One of those existing fusible links broke again. I don't think it melted, just brittle. At any rate I cut them out and attempted to solder them in. Turns out the soldering gun that hasn't been used in 20 years but has followed me around the country doesn't work. It is good at burning me, bad at melting solder... so crimped again. We'll see how it goes with these new links... I used 14 gauge.
Anyone know what exactly the glow plug relay is supposed to do after the WTS light goes out? Before I changed my plugs, once the light went out (~15 seconds normally), the relay would cycle on and off for awhile. Now, the WTS goes out after 15 seconds, the glow plugs appear to stay on for about another 30 seconds (looking at the battery gauge on the dash), then it clicks once and goes off. How's that sound? Working as it should?
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