Another GP question.

[OLDBULL8]

Could it be why so many guys burn out there GP's, that when they bypass the GP controller that the GP harness is connected directly to the Relay (Solenoid) output side terminal. Doing that, the ZigZag Chromalox (resistor) will not control the inrush current and voltage, as the GP cycle continues, the ZigZag heats up creating a higher resistance reducing the voltage to the GP's. It's true that the 12.8 battery voltage reduces to ~8.5 VDC within about ~2 seconds. Two point five volts (2.5) over on a six volt (6) GP will not destroy it, but ~10 volts might. I've not measured voltage with the ZigZag bypassed. Just a thought.

 

[icanfixall]

You might be correct Bill. I have never advocated ruining a push button glow plug system. I feel the solid state controller does a good job. I don't think I have ever burned out a beru zd9 plug yet. I did burn out most of the autolites and champions I had in the engine when I bought the truck. All I knew when I got the rig was its a diesel. Not much more. I really did not know about diesel specific oil or about the fram oil and fuel filters. I have learned...

 

[laserjock]

Bill, Any idea what the resisance is on that thing? You are right, it probably would soak up some in-rush current. I don't know though, you would think the harness would soak up a bit. It's resistance isn't zero. Do guys actually remove the controller? I thought most of them just left it in place and and bypass it. That would leave the strip in the circuit.

I always figured it was just a fine line with the controller on the side of caution. Any time humans are involved, the probability of failure and error increases dramatically. In this case, it's not like we have any feedback from the system. You just push the button and count then hope you were right.

 

[cpdenton]

When I added my push button control, I didn't take out the zig zag resistor. It's still in there.

I only added a manual ground switch that controls the relay. The power is still supplied through the same power system that was there originally. Perhaps this is why all my glow plugs still seem to be ok?

 

[OLDBULL8]

I don't know though, you would think the harness would soak up a bit. It's resistance isn't zero.

No, you could say the resistance is ZERO. Actually the 10 Ga wire that feeds the GP's the resistance is 0.999 per one thousand feet (1000) depending on the ambient temperature of 72*F. The short 14 Ga wires are nil.

 

[Agnem]

If you tried to measure the resistance of that thing, it would show zero. It works a little bit like the filament in a light bulb. The resistance is zero without a load, but increases with current. The voltage drop across the strip is what the controller looks at to determine glow plug heat and glow time.

 

[rpm427]

Are the ZD9 Motorcrafts OK to run in truck as I see them for sale all the time with NO Beru behind Motorcraft?

 

[Zaggnutt]

Are the ZD9 Motorcrafts OK to run in truck as I see them for sale all the time with NO Beru behind Motorcraft?

Same thing, brother. Sometimes labeled Motorcraft ZD-9 and sometimes packaging will say BERU.