Pondering Glow plug issues.

[bbjordan]

So for those with a push button system, beware, you are not solving a problem and it will leave you with a no start trying to get home in a blizzard.

That's why I carry a can of ether in the truck. Having the push button also gives me the option to use ether without having to disconnect anything. Also, with the system I have: one 30 amp relay/plug I now have the ability to monitor the relative temp of each cylinder. This allows me to tell if a plug is burnt out too.

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[Macrobb]

Y'know, I solved the manual glow plug problem with a low-tech solution: Add a 9th glow plug, in the cab. Now, you can watch it heat up, and act accordingly.

Speaking of frying glow plugs, The resistance in the wiring matters a /lot/.
In my 88 F250, I used:
1. 6.9-style glow plugs
2. 7.3 relay mounted on the passenger fender plate.
3. 7.3 resistor strip
4. Individual 10-ga wires to each glow plug
5. 9th glow plug in the cab, on 10ga wire
6. push button to control it all.

One winter when it was /really/ cold(and I probably plugged the filter), I just kept holding the button longer and longer trying to get it to start.
After giving up and finally using a /lot/ of ether and cranking to get it running, I ended up finding that the two front glow plugs, which each had shorter wires(by perhaps 6 inches) from the controller(I ran the wires behind the alternator) fried. The others were more tolerant.

I think at one time or another I fried a few more glow plugs(user error); it was always the front ones. The back ones were evidently cooler, as they had longer wires.

 

[hce]

Why your finger burns out glow plugs, is pretty simple. First is you bypassed the factory system for some reason, probably due to hard starting issues somewhere other then the glowplugs. More finger time on the button is being used to compensate for the other issues causing hard start. Glow plug one fails due to overheating, making the engine even harder starting. The remaining 7 stressed glow plugs start failing from even longer finger cycle times to compensate for the one lost, less glow plugs the longer and harder one pushes the other glow plugs.

 

[Hydro-idi]

I really like the stock GP system in these trucks. The 12v systems that is.
Plus if you buy a GPC from Azone, it comes with a lifetime warranty.

 

[franklin2]

I believe what Russ was commenting on was when you change to a push button glow system... You are sending power to only the working plugs and that ends up too much so it burns out the remaining plugs. I'm no electrician but I know just a little about some things. This wont be the only time I'm wrong either so let the schooling begin.

Don't think of the batteries "shoving" power into the glowplugs, and thus shoving too much into the remaining plugs. Think of the glowplugs as "drawing" power from the batteries. Less glowplugs means less power being drawn from the batteries.

That's why when guys are doing tests with individual glowplugs, they just hook one up and don't have to hook all 8 up to see when a tip swells or how long it takes for the plug to turn red or burn up. The only difference would be the voltage drop inherent in the system. One glowplug hooked directly to the battery will have very little voltage drop, so in that test situation that glowplug would see near 12v.

 

[Runningaford]

I think Franklin is correct, the load determines the draw. Think about lights in your home, you replace a 150 watt lightbulb with a 40 watt lightbulb... The 40 will run all day long, 'pulling' less amps than the 150w bulb; which means less heat which is less resistance; meaning less voltage drop. Look up Ohm's law, and plug in the numbers.

Think about the lightbulbs like glow plugs, just cause you 'downsize', or have fewer drawing power, doesn't mean the fewer get more amps, they themselves due to their resistance determine how much power they get.

 

[hce]

yeah, pretty much have to go with franklin also.

 

[typ4]

Again , not a load post. Its about uncontrolled time post.
Real time on the truck testing/ failure. Not should ,could electrical behavior.
I know how current flow works. That's not the issue.

 

[BrianX128]

Both parties are right, just different elections being held.. haha

 

[typ4]

I'm done trying to explain my point, half get it , half don't.

 

[towcat]

it's time this thread is done.