My 87 is having glow plug issues. There is power to the controller through 2 heavy yellow wires but no power to the plugs themselves. The plugs all check good. I think my next move is to replace the relay looking thing on the top of the controller. Is this correct?
Glow plug problems
- Thread starter Jbevs
- Start date
smolkin
Stuck inside Mobile
I recommend checking the wires from controller==>gps for continuity/ resistance. I was going to just replace my controller, too, but on a whim I checked the wires and, lo and behold, 5 of 8 burned out and very high resistance on the other three. Now I'm building a new harness and switching over to manual, so I don't have to do this ever again! (I hope) My dual-coil gps will be in Thursday, and then, for the first time EVER, I should have working gps on a truck I own!
Somewhere in the tech articles is a write-up on the controller I think. You do have bullet-type gps (I think some '87s had bullet, some blade), right? You can replace just the relay part but you will want to make sure the other bits are OK, too. Or: replace controller as a unit, or convert to manual like me, especially if you have the blade-type (which are 6V; you would have to change out with bullet-types [12V]).
Somewhere in the tech articles is a write-up on the controller I think. You do have bullet-type gps (I think some '87s had bullet, some blade), right? You can replace just the relay part but you will want to make sure the other bits are OK, too. Or: replace controller as a unit, or convert to manual like me, especially if you have the blade-type (which are 6V; you would have to change out with bullet-types [12V]).
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smolkin
Stuck inside Mobile
If your meter has a continuity/ diode test mode, (looks like " -->[ ") use that, or test for resistance; it should be very low. First, unplug all gps and then take the 2 wires for the gp banks off the relay and test. I think the bullet connectors are the weak point, and vibration-caused fatigue and corrosion gradually create higher resistance, and finally something burns up. You can just replace the connectors but I opted to do the whole harness and get rid of the 23 yr old mess.
Blind Driver2
Full Access Member
You don't need battery voltage to check the wires. Check for Ohm resistance. I don't know what the resistance values should be for that gauge wire. But if the meter goes --- , that's infinite Ohms...meaning no voltage will travel through the wire.
icanfixall
Official GMM hand model
This may help you out....
http://www.ebay.com/itm/160792630172?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
http://www.ebay.com/itm/160792630172?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
89dieselbko
Full Access Member
i know this if off topic, sort of but it still kind of works...
Does anyone out there know what part # for the connectors for the glow plugs. a while back i made a new harness but my connectors were bad, i have been meaning to ask if anyone had a name or part # for them. Going to be tearing into my IP friday/saturday and while im under the hood i figured i may as well replace my GP harness with my new one. Thanks! and sorry for the hijack, didnt want to fire up a thread about GPs with one active already
(this thread reminded me i still needed to find the info on the round connector things)
Does anyone out there know what part # for the connectors for the glow plugs. a while back i made a new harness but my connectors were bad, i have been meaning to ask if anyone had a name or part # for them. Going to be tearing into my IP friday/saturday and while im under the hood i figured i may as well replace my GP harness with my new one. Thanks! and sorry for the hijack, didnt want to fire up a thread about GPs with one active already
(this thread reminded me i still needed to find the info on the round connector things)
smolkin
Stuck inside Mobile
The gp connectors are standard .157" bullet connectors. You should be able to find them at auto parts stores, Home Depot, maybe Walmart. To be sure do like I did: go to Autozone, ask them to pull a bullet-type gp from the shelf, then go to the electrical section and find the right size. Then, give the gp back to the dumbfounded cashier and get a refund.
Actually it was the 9v battery in my multimeter that died. Pretty rediculous. I will check all my other gp wires, but I don't think that is the problem. Pretty sure at this point I will be needing a new gp relay.
Is the large terminal on the relay that is attatched to the z strip only hot when the gps are on, or hot all the time the key is on? If I had bad wiring to specific glow plugs, wouldn't that cause the WTS light to only stay lit for a few seconds, same a burnt out gp's?
'94IDITurbo7.3
HAMMER DOWN!
large terminal that z-bar is connected to should ONLY be on when KEY IS ON. i am not sure about bad wiring to plugs causing WTS light to go out faster.
'94IDITurbo7.3
HAMMER DOWN!
http://www.ford-trucks.com/forums/1110673-no-click-from-glow-plugs.html
so good glow plug diag info ^^^^^^
edit: from the sounds of it you are using the 7.3L glow plug system?
so good glow plug diag info ^^^^^^
edit: from the sounds of it you are using the 7.3L glow plug system?
smolkin
Stuck inside Mobile
Yeah, it sounds like you have more going on than just bad wiring. Here is an article about bypassing the controller but it has a decent explanation of the system, if you haven't read it already.
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I am using the 7.3 system, as I think most 87's do. I am also pretty sure that it's not entirely fubared. I'm going to replace the relay and see where I am.
I have read that thread smolkin. I do get the click and cycling, at least it tries to.
I have read that thread smolkin. I do get the click and cycling, at least it tries to.
Yesterday I replaced the relay on top of the controller. No change. 
I am never getting power to the z strip, even when the WTS light is lit. I am going to replace the main power wire (2 yellow ones) just to make sure a bad connection is not in there is cutting out when it tries to draw the real power. When the key is on, all other posts on the relay have power. I forgot how these relays actually work.
I am never getting power to the z strip, even when the WTS light is lit. I am going to replace the main power wire (2 yellow ones) just to make sure a bad connection is not in there is cutting out when it tries to draw the real power. When the key is on, all other posts on the relay have power. I forgot how these relays actually work.
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