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best glowplugs for a 6.9 IDI with manual control

iamdave0887

Here Comes Chaos.....
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A buddy just bought an 86 F350 with the 6.9 diesel in it. we've had our first cool day, and the truck didn't start. it just smoked from the exhaust but never caught.

I believe the controller is bad as it'll come on for about 5-8 seconds then it'll constantly click on and off rapidly even with the engine running, and it never stops until you turn the key off.

What glowplug can he install that he can use a manual push button setup to control and delete the factory GP controller all together?

I can get a decent deal on the Bosch #80024 glowplugs, but i've read that the tips tend to swell on them.

Thanks guys.

- Dave
 
BERU(MOTORCRAFT from AZ) is the factory plug and only plug to run with the stock controller. If you want to manually actuate them, then ACDELCO 60G's are the way to go. The stock 6.9L and 7.3L glow plug systems are 6 volt systems. So if you hook up a solonoid and switch they will not last long at all.
 
BERU(MOTORCRAFT from AZ) is the factory plug and only plug to run with the stock controller. If you want to manually actuate them, then ACDELCO 60G's are the way to go. The stock 6.9L and 7.3L glow plug systems are 6 volt systems. So if you hook up a solonoid and switch they will not last long at all.

I checked for voltage at the GPs real quick when he went to buy the truck. I got ~12 volts, and the glowplug system is stock. The GP relay looks just like the solenoid for the starter. There's no resistor like the 7.3 has in it.

Your sure the 6.9 IDI system was 6 volts? I know the 7.3 IDI system was a 6 volt system as the voltage was dropped over that large resistor coming off the glowplug solenoid terminal which then went to the glowplug harness.
 
Late 6.9's were supposed to have the 6 volt like the 7.3's had, early 6.9's had a 12 volt. Sounds like maybe somebody put in an earlier system.
 
Did some digging and found that 87 was the change over to the 6 volt glow plugs, so only 1 year of the 6.9's had em. 86 should be 12 volt with the spade type terminals on them(bullet connectors are for the 6V plugs). The purple wire to the glow plug solonoid is the one that you hook your momentary switch to for manual glow plug engagement. As for which glow plugs the MOTORCRAFT/BERU are reccomended, but I believe a set of AC 60G's will work as well for manual operation(they don't work well with the stock controller though).
 
Thanks :)

My buddy bought this truck for $500, so he's looking to get the glowplugs working as easily as he can. It definitely needs new ones, but the controller is what's expensive. The controller looks like the 84 and older 6.2 controller, and i know those were junk.

Yes these glowplugs have the spade terminal on them. They aren't the bullet connector.
 
I've got an '84 and it has the spade GP's and it's 12 volts, stock. I would only use BERU GP's.

IIRC there is a helpful forum: FTE forum. You'll find alot of good info. including the wire diagram.
 
I've got an '84 and it has the spade GP's and it's 12 volts, stock. I would only use BERU GP's.

IIRC there is a helpful forum: FTE forum. You'll find alot of good info. including the wire diagram.

BERUS are like the AC 60G's, self regulating. The big problem was that ONLY BERU makes a self regualting 6 volt plug. The others out there that most run are not a self regualting, and when one goes out the voltage to the rest goes up some. Also when one goes out, the glow plug controller will keep the other plugs on longer worstening the problem. INTERNATIONAL makes an updated solid state controller for the 12 volt system, but it is about $275. A set of self regualting glow plugs, a FORD starter solonoid, and a momentary switch is ALOT cheaper.
 
We went with genuine Motorcraft/Beru ZD1A glowplugs. It had champion's in it, and one was already swollen :eek:, but not to the point where it didn't come out. All the old plugs were wet with diesel when they came out.

After we changed them all the controller held them on for about 8 seconds, then started pulsing them on and off again and didn't stop until the key was turned off. That confirms the controller's toast. Time to wire in a pushbutton me thinks. Seems the controller in the head is the same style as the one used in the 82-84 6.2s, and i know those were garbage, so there's no sense in replacing it.

On the first start with the new plugs the ol girl needed about 1/2 a turn before she was running, so they are definitely working.

Now onto why the cold advance/high idle doesn't seem to be working. The Stanadyne water separator has been bypassed as well. I know why it's been bypassed now, but the owner has seen a WIF light in his daily driver 7.3 PSD as recent as last week, so i think i'm gonna take a stab at re-attaching it and finding out what's wrong.
 
The GP controller, if I remember correctly, is located in the block back by the firewall. It cost nearly $200 to replace. If you attempt to remove it and it breaks off you'll have a difficult time finishing the removal, and have a water leak to boost. Just leave it.

Install the manual switch. It leaves the controller totally out of use. It become only a plug in the block.

The water separator is probably bypassed because when the release was pushed to let water out the drain they often did not seal correctly and the engine now has air entering the fuel system.

I found a water/fuel separator on Ebay that was off of a Komatsu dozer for $15-$20 dollars. It is mounted in the same location. You can actually see if there's water inside, and it seal easily and is tight. Much better then the original.

Oh, and Champion GP's had the worst reputation for expanding and causing trouble removing the the 6.9s.
 
For the cold advance there should be a 2 wire sensor threaded into the front of the block which powers the cold advance and throttle advance solonoids. You could always wire them to a toggle switch inside teh truck for him to turn on for cold starts.
 
For the cold advance there should be a 2 wire sensor threaded into the front of the block which powers the cold advance and throttle advance solonoids. You could always wire them to a toggle switch inside teh truck for him to turn on for cold starts.

Works just like the 6.2's advance and fast idle solenoids, save for the 6.2's temp switch is in the rear of the passenger side head.
 
I don't have a switch in my 85 6.9idi I just spray diesel starting fluid in the intake and it comes right to life!
:nailbiting: starting fluid with an idi can be dangerous and addictive. Seen to many engines get to where they won't start at all without a wiff from using it, eventually the wiff becomesa fogging, then they don't start no more.
 
Just bought a 6.9 to replace the 460 gas job in my 86 f350. I also purchased a set of 60 gs for it. They look a little too short to fit the 6.9. As they are for a 6.2
Nope, wrong one. For the 6.9 you want an Autolite 1115. It is the self regulating one for that engine. Remember to use a little anti seize on the threads when installing plugs.

Make sure your dmv will allow gas to diesel conversion- some places don’t.
 
Nope, wrong one. For the 6.9 you want an Autolite 1115. It is the self regulating one for that engine. Remember to use a little anti seize on the threads when installing plugs.

Make sure your dmv will allow gas to diesel conversion- some places don’t.

I wouldn't run autolite's myself, heard of way to many swelling in the heads. And I looked up the 1115's, and I don't believe they will work with the stock glow plug system as they are 11V plugs. Beru(Motorcraft) only is what I was told for the International engines. And if you do away with the stock 6 volt glow plug system and go to a toggle switch with a straight solenoid (no resistor), then you run 60G's.
 
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