Aright guys I know this is a beating dead horse. But hopefully this thread can shed a little more light on the issues.

First question in florida weather 95 degrees out, do you need glow plugs to start a healthy 6.9 diesel?

If the answer is yes, then delete this thread and let me know lol. If it is no, then I need to figure out my start problem.

Cold motor, it takes between 5-10 turns for 5 secs about thirty seconds apart to start it. I am getting 12V at the relay in and out. This of course doesnt matter because my glow plug controller is blown. Relay is good but controller is out, i have done the test that is posted everywhere here. I have 12v at the starter also. Batteries are new and good, two deep cycle, one crank and one trolling hooked up in a series (600CCA)

The alternator pumps out 14v while running charging the batteries back up. The starter is recently rebuilt and a new 3/0 cable is on it, with a new 3/0 cable ground.

Oil pressure while running is around 20 while idling and up to 50 max revving (i think).

All the connections are tight everywhere and when it runs it purrs like a kitten not rough like it has a blown headgasket or a misfire leading me away from a low compression problem.

I dont believe there is a leak in the fuel lines because once it runs it doesnt sputter and show signs of a bad idle.

The kicker: This is an 1984 bluebird bus, but honestly some of the bus guys arent as knowledgeable as some of the guys here. It has the 6.9 in the older f250s.

Please shed some light if you can.

 

Almost 40 views and no one?

 

in my opinion first start of the day yes other starts no

 

but if the controller is blown the gps wont turn on at all

 

replacing your controller should solve your no start issue

 

Might I add that once its started and warmed up it can be shutoff and started up like a brand new 1984 6.9l!

I know the GPs are a problem but I want to trouble shoot otherwise as there def is another problem somewhere.

 

I imagine the GPs need replacing and I will also while doing the controller. I didnt think I should need the plugs in florida summer heat.

 

i use my glowpugs to start in the mornings when it is 85 outside it works every time even if it is 95 outside. if the motor has been sitting for a while it will be colder than the ambient air due to it being in a dark space so the gps need to be addressed first then see if there is any other problems if the starting issue is still the same

 

Yes, You need Glow Plugs ...

If you know your controller is bad, replace it, if you need testing procedures ask ...

Or you can hack the system to manual Glow Plugs that'll wind up costing more then the controller if anyone drives the truck that can't count seconds accurately!

Or better yet, Upgrade to the SS Controller ... From the 87-94 motors!

-Enjoy
fh : )_~

 

Thank you for the input guys. I need to search around to see what all is involved with the GP controller upgrade. I just figured that I shouldnt need GP's in florida heat.

I guess a set of motocraft GP's are in store for the change as well.

 

I am going to try the manual switch as well, from my understanding and searching, this bypasses the controller correct?

You pull the white wire (which i dont have bc its a diff vehicle) from the starter relay and hook that up to your switch with a ground and power source correct? If so what is the white wire supplying power to or from before I pull and which terminal is it going to be on big one or little one. How do I find out which wire it is?

Thanks for all the help again.

 

Just saw a set of ZD9's on eBay for $77 free shipping, I have purchased from the same seller and they are the real deal!

However you need ZD1's unless you upgrade your harness.
The ZD9 uses a bullet type connector and the ZD1 uses a 1/4" spade type connector, otherwise they are basically the same.

As for the upgrade, the best thing to do is goto a junk yard and grab the wiring harness off a 87-94 IDI, the controller if it's there and works, else buy a new controller.

Then you just need to blend the 87-94 harness to the 83-86 engine bay harness.

-Enjoy
fh : )_~

 

No ... Incorrect, That is for the newer system as well as incorrectly understood ... You do not ground the white wire, you ground the relay terminal the white wire was attached to.

However that is NOT for your truck ... The following is!

For you to do a manual setup.

1. On the inner fender (not fender) is the GP Relay.
2. Remove the Purple wire.
3. Run a wire from one leg of a push button to the small terminal on the relay you removed the purple wire from.
4. Run a wire from the other leg of the push button to fused 12v+ power.

Personally I consider it a hack! And that is just my opinion!

-Enjoy
fh : )_~

 

I agree it is a hack Fetus, but at the same token I would like to see if that is my starting issue and it seems like this is the way.

Sorry for the questions man, but the purple wire is the power out to the controller? It sits on the GP relay and on the big or little terminal?

 

I'm too old to be a Fetus ... But I would sure like to be one again, I would live a new life in a different way!

The Purple wire is the Signal wire FROM the Glow Plug Controller that energizes the Glow Plug relay and turns on the Glow Plugs.

You can test it just by applying 12v+ to the relay terminal that has the purple wire ... Remove the purple wire and apply 12v+ to the small terminal you removed the purple wire from for NO MORE THEN 10 SECONDS!!!

Here is a procedure to completely test the glow system ...
***** The following assumes you have already checked cables, connections, cab, chassis and engine grounds. *****
***** That the water temp is below 112F degrees. (ie: cold motor) *****
***** When testing energize briefly, long enough to get the answer, no need to overheat things and no more than 10 seconds *****

Unplug the forward most (towards front of truck) connector on the Injection pump, this prevents overheating the FSS.

*** Glow Plug Test. ***
Test light test of the glow plugs:

1. Unplug the Glow Plugs.
2. Attach one end of a test light to 12v+ battery.
3. Touch the other end to the terminal on the end of the Glow Plug (where you unplugged the harness)
   Does it light up?
   • Yes, Chances are it's good.
   • No, Replace with Motorcraft/Beru ZD1A for 83-86, ZD9 for 87-94.5.
   This test is susceptible to miss diagnoses and should only be used for a quick reference.
   To do a positive test use a volt/ohm meter and test the ohms between the terminal and base. Should be .5 to 1 ohm resistance.

Test that you get power to the glow plugs:

1. Unplug a glow plug.
2. Attach one end of a test light to the glow plug wire.
3. The other end to ground.
4. Momentarily turn the key on while watching the test light.
   Does it light up?
   • Yes, test Glow Plugs.
   • No, test Controller, Relay.

*** Pre '87 Controller, Relay test. ***
The relay is attached to the right (passenger) inner fender and has 4 terminals.

• 1 large terminal (Input Terminal) goes to full time 12v+. (battery)
• The other large terminal (Output Terminal) goes to the glow plugs.
• 1 small terminal (Power Terminal) is controlled 12v+ from the controller. (Purple wire)
• The other small terminal (Ground Terminal) goes to ground. (white with black tracer (I think))
  
  Ensure there is 12v+ to the Input Terminal of the relay.
  Ensure Ground is good, both the base and Ground Terminal.
  
  Relay test:
  1. Attach one end of a test light to ground.
  2. The other end to the Output Terminal of the relay.
  3. Remove the small purple wire from the glow plug relay Power Terminal.
  4. Momentarily apply 12v+ to the Power Terminal on the relay. (where purple wire was)
     Does it light up?
     • Yes, relay MAY BE good.
       • Test voltage at the battery and the Output Terminal on the relay while relay is energized. BE QUICK. (10 seconds or less)
       • Voltages should be close to the same. If not replace relay.
     • No, Relay is not working.
  
  Controller test:
  1. Attach one end of a test light to the relay Power Terminal (purple wire, do not remove from relay)
  2. The other end to ground.
  3. Turn the key on while watching the test light.
     Leave the key on until the test light goes off (or cycles) or 10 seconds which ever occurs first.
     Does it light up?
     • Yes, The controller MAY BE good.
       • Does it go off by itself? (It may cycle, thats good)
         • Yes, Controller is good.
         • No, The controller has FAILED ON ... Replace!
     • No, The controller is bad replace.

-Enjoy
fh : )_~