She eats glow plugs

540milotalon

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I may have posted here but can't find it. I did post on another site.
Friends truck, 1985 6.9 IDI with '92-'97 front clip.
Truck consumed a couple sets of glow plugs.

A couple people have worked on it.
I came in after the second or third set of burn't plugs.
A younger fellow installed the glow plugs, "BERU" and the low pressure return caps, o rings and hoses. He installed inline two (2) check valves (supply and return lines) so fuel would not syphon back to tank.
In doing this he tightened a 5/8"hose clamp on the hose above the metal line and yep, it drained fuel off.
I fixed this, added in line an electric fuel pump to aid in purging air.
I removed the Glow Plug relay and replaced, installed a push button momentary contact switch and light and required wiring (like my old '85 which was totaled) and got the truck running last Sunday, 13 Feb and after it ran to warm up, removed electric fuel pump and allowed it to run on mechanical pump. Owner went to start on Wednesday 16 Feb and she kicked off once and cut off, then nothing but crank.
I stopped by with battery charger and checked glow plugs on a lark and found, they were gone again. So, we now have burned up two (2) more sets of plugs marked "Beru." This is since the kid worked on it.

Between the IDI trucks my family own, 5 that will start up, two with current tags on them, we have never to our recollections replaced ANY glow plugs. Relays, several times but not one plug. I have replaced them in the Powerstrokes though. I have three of those.

This truck has me completely whipped. The owner is at 5-6 sets of glow plugs, at least 3 of which said "Beru" on them.
 

Cubey

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Owner went to start on Wednesday 16 Feb and she kicked off once and cut off, then nothing but crank.

Sounds like a fuel system problem there, not glow plugs. Are they running the glow plugs way too long on the manual control switch thinking that'll fix the fuel system problem?
 

Austin86250

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could your timing be too advanced? i think too much advance eats glow plugs
 

Black dawg

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I am assuming you are using the 6.9 spade connector beru plugs? How long are they being glowed....they dont put up with much more than what is needed. Usually 10 seconds or less.
 

Big Bart

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Some other thoughts.

1) Something is setting off the glowplug relay. Perhaps the activation wire is arcing out on ground or positive. Thus causing the plugs to go on. Kid, dog, purse, backpack, or ????? Is pushing the momentary button?

2) Glowplug wiring harness is finding power somehow. Like it is sitting on the fusible link harness and both wire sets perhaps have rubbed through and touch at times. Thus turning on and burning up the glow plugs.

3) If not already I would wire the GP light to go on when the gp harness gets 12v power. Confirm inside the truck it is not randomly getting power at times. (You may have it this way, sorry if you do.)

4) Does the truck have an EGT gauge? Maybe this thing is running hot?

5) Ditto on set timing. It effects egt’s and block temp.

6) Fuel and additives. Ask where and what type of fuel they are using? Old, bio, other? What additives do they use and how much? Adding a entire quart of diesel kleen is not better than adding the correct amount. Maybe they are using a random chemical that is problematic for the GP’s. (Like synthetic oil or 2 stroke.)

7) As mentioned above they are running the glow plugs way to long. Like back to back for 20 seconds due to drain back and hard starting.

8) Here is a lead to chase, maybe it is a bad ground or supply. Check the battery cables (Many are now split and have corroded.), pull and clean the ground block (Very plausible), gp harness, check the fusible links and mid harness connector (One link is dead other is marginal.) Perhaps you have a bad/poor/corroded connection. That is causing a voltage drop and higher amps thus burning up the entire set. (VS 1 or 2) Most likely the ground would do this but potentially the fusible links.

Realistically it would need to be
1) Plugs go on or stay on too long. Short, user error, or by accident.(Farmers dog standing on the switch while in a store.)
2) Super high egt’s.(Timming/fuel.)
3) Something in the fuel or in the oil reacting with the glow plugs.
4) Voltage drop/poor connection causing high heatduring use.


Let’s us know what you find and send some pics.
 
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IDIBRONCO

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by accident.(Farmers dog standing on the switch while in a store.)
As funny as this may sound, I did see something similar to this before. I knew an older guy who had a giant Doberman that he took everywhere with him. I saw his truck in front of a restaurant one time and the brake lights were on. Thinking that he had just pulled up and was sitting there with his foot on the brake, I parked and walked across the street to talk to him. I couldn't walk directly across behind his truck so I couldn't see inside. When I finally got close enough to see inside, it was empty. I got right up next to it and looked inside to see his dog laying on the floor on the driver's side right up against the brake pedal. He and his wife were inside about half way through breakfast and had no idea his brake lights were on.
 

The_Josh_Bear

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I think we are all thinking the glow plugs are burnt out when he's saying they are physically missing. Or are they just burning out?

Sounds like he's saying they are eroding which is a timing or dribbling injector issue. I've only heard of it though, I'm no expert. It has to be way advanced to erode the plugs.
 

IDIBRONCO

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One of the injectors that I had rebuilt when I first built me Bronco was leaking after about a year. I had one cylinder that always had the end of the glow plug burned off of it.
 

Big Bart

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I think we are all thinking the glow plugs are burnt out when he's saying they are physically missing. Or are they just burning out?

Sounds like he's saying they are eroding which is a timing or dribbling injector issue. I've only heard of it though, I'm no expert. It has to be way advanced to erode the plugs.
It’s a oddity that 8 glow plugs die or erode in 3 days.

It will be interesting to see what he finds.
 

540milotalon

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I appreciate all the responses. We are manually holding the button 10-15 seconds like my daughters '94 Factory ATS Turbo 7.3.
What this modified '85 does NOT have is the GPR resistor on it. My '83 has it, I think my '85 had it but it was totaled and parted out in '06.
Plan is to replace the GP tomorrow or Tuesday and add a resistor and measure current to the plugs.
 

74frankenford

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I appreciate all the responses. We are manually holding the button 10-15 seconds like my daughters '94 Factory ATS Turbo 7.3.
What this modified '85 does NOT have is the GPR resistor on it. My '83 has it, I think my '85 had it but it was totaled and parted out in '06.
Plan is to replace the GP tomorrow or Tuesday and add a resistor and measure current to the plugs.
I think 15 seconds is a long time to manually hold for glow plugs.
 

asmith

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As funny as this may sound, I did see something similar to this before. I knew an older guy who had a giant Doberman that he took everywhere with him. I saw his truck in front of a restaurant one time and the brake lights were on. Thinking that he had just pulled up and was sitting there with his foot on the brake, I parked and walked across the street to talk to him. I couldn't walk directly across behind his truck so I couldn't see inside. When I finally got close enough to see inside, it was empty. I got right up next to it and looked inside to see his dog laying on the floor on the driver's side right up against the brake pedal. He and his wife were inside about half way through breakfast and had no idea his brake lights were on.

We have a Doberman and I take her as many places as I can. I have come out to the truck on several occasions to the brake lights on and her curled up against the pedals. She doesn't do it as much anymore now that she is full grown. hard to get all 90 pounds of her down in there these days.

As for the glowplug problem, I vote timing is way off. either that or all the injectors are leaking badly. I dont see anything else cause all of them to be eroded away so fast. maybe a combo of holding the button too long and burning them out with timing being off so they erode faster?
 

danno

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Hey OP... any resolution on this? My '86 IDI+T(ATS stock) seems to have just burned up a second set of GPS in 5 months. I also have a momentary switch that I do 10 seconds on for cold start. Only thing I can think of is bad injectors (I have new ones i'm about to install from Accurate Diesel) and/or high EGTs since i've been towing heavy and have been seeing EGT's in the 1000-1100F range on steeps. Doesn't seem to me like a GP which is essentially a heating element, would be burner out by high EGTS.
 
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