A single battery at 11.8 is insufficient. Two batteries at 11.8 are insufficient. With nearly brand new batteries, new cables, and new starter I did manage to forget to connect one of my batteries and the engine started just fine but that was under fairly ideal circumstances. A 12v battery needs to maintain 12.7v or it's on the road to failure.

 

Reading through this thread. There is the mention of both types of Glow Plug
Relay/Controllers.
83 - 86 and 87 - 94.
87 - 94 doesn`t pertain to you, grounding out the white wire.

You have the early style with the Controller screwed into the Head on the drivers
side, with the Relay on the Passenger side Fender behind the Battery as you
show in your video`s.
One thing I would do is solder on ring terminals at the relay, and some flat spade
connectors at the Momentary Toggle switch. instead of twisting wires together.
You will get a more positive connection, and heat Shrink it.

Your Starter relay looks pretty rusty and corroded, be sure to clean up the connections,
or replace the relay and use some Dialectrical grease.
Make sure all Ground connections are clean, at the engine Block/Starter.
The cables at the battery can have corrosion going under the cable sheath, and that
will cause high resistance.

As mentioned, you need fully charged Batteries, and if they don`t hold a good charge
or they drop off quickly,, replace them with a good set of group 65`s.
I replace mine every 4 years just before winter. I use Interstate`s from Costco.
I have had my 86 10 years now, did replace all Battery Cables as they were cracked
all along the full length through the cable covering. Had them made at NAPA with Ring
terminals on the ends.
Even replaced the pos + wire from battery to GP Relay/Starter Relay to a bigger size, maybe
6ga. Also using a Power Master 9050 Starter.

Using Motor Craft ZD-1 GP`s, 6 years coming up on us this winter facing us, and so far haven`t
failed me.
Did or does your 83 have the Fuel Water Separator on the FW next to the Brake Booster?
Gave mine the deep 6, and there is an electrical plug that went to it. The Red wire is pos +
with the key on. I used that wire, soldered in an inline Fuse, ran to Momentary Toggle, and other
side of Toggle ran Wire (like you did) to the GP Relay.


Charlie

 

Just installed the new starter motor, new starter solenoid, and still having a weak crank w/ 12.8v for both batteries! Noticing some corrosion on the positive battery cables, and though it was not a concern when I first got the truck it seems that must be the limiting factor now. The motor sounds strong but its not getting enough voltage. Have a new positive battery cable coming in tomorrow, and for good measure also replacing the battery to starter cable and the original negative cables.

 

Hopefully that fixes your issue. At one point I had brand new batts, new custom oversized battery cables, all grounds new and larger gauge wire, new starter, and that thing would turn over so fast it startled people.

 

Installed new battery to starter cable and new positive battery cable. Still having the hard start issues and a weak crank per the video! No idea what else could be causing the issue, even my manual glow plug switch is not working properly it should not be starting that weak. The starter to battery cable does seem to be a smaller gage even though I tried to get ones which others have used before but I'm not sure if that could be the issue. For good measure I also cleaned the negative battery terminals which connect to the engine. Any suggestions?

 

that sure sounds like bad batteries to me. they start cranking fine, than crap out.

 

Yup, just got a brand new group 65 850 CCA. Sounds much better w/ just 1 batter, now I think the issue is just the manual bypass not working correctly

 

yup. that did it. time to check a few glow plugs.
try holding for 10 seconds first though. you may just not be heating them enough.

 

Went again for 10s and no luck. Tomorrow will check for 12v on each of the glow plugs while holding the momentary switch and go from there

 

Things are looking even more screwy.... when checking the voltage of the post that the bypass switch is connected to I am reading fluctuating voltage from 0 to ~11.5v without pressing the button. No idea what could be causing it. Any pointers or ideas where I can get a wiring diagram to sort this out? I believe I have the early glow plug wiring given where the controller is located. Per this website which talks about glow plug controller issues (http://www.intellidog.com/dieselmann/idi2.htm) it seems that I do in fact have the early 6 pin engine to chassis connectors.

 

Found the original early 1983 wiring diagram (https://www.thedieselstop.com/attach...em-jpg.113970/). Jumped the ground on the glow plug solenoid to the battery negative and glow plug solenoid and switch working perfectly. Working through the glow plugs now, just leaving this info if anyone runs into the same issue

 

1987 F250 6.9 International Diesel
1 glow plug has no steady or solid period in the dash light before blinking.
2 relay ignition & glow plug terminals blink when relay clicks/blinks
3 glow plugs all good - battery to glow plug check
Is relay bad? Or is there something in the controller other than the relay?

I know I can bypass, but if problem is relay, would rather R&R. It's only $31, not $110.

6.9/7.3 glow plug relay

 

only way to know for sure is to test the relay.

 

Understood. Sorry, have to show my ignorance. How to check the relay?
Large to large terminals, when? Small to small, when? When ignition is on? When switch is on start?
The WTS light does not come on or work. The rapid cycle clicking starts immediately when ignition is turned on. Engine does not crank as if glow plugs are working properly.. I have used block heater to get through winter.
Glow plugs test hot when tester connected to battery+. Assume all good.
Cannot remember large terminal test result.
Hoping for $31 relay, not $110 whole controller.
Thanks

 

to test the glow plug relay i remove it. put 12 volts to the two small terminals. check resistance between the two large terminals. it should read zero ohms.

have you looked at the glow plugs? what brand, and how old are they?

the glow plugs themselves could just be bad.