84 Deisel Glow Plug Problem?
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Joined: Nov 2007
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From: Houston/Praha
84 Deisel Glow Plug Problem?
I have an 84 f250 with a 6.9 deisel that is really getting hard to start. When it finally does start, the glow plug indicator light on the dash flashes on and off. Are both of these a sign of one or more bad glow plugs?
Allen
Allen
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From: Virginia
The indicator is supposed to flash, it's the controller modulating the glowplugs after the engine starts.
Get a testlight and hook one end to the battery +. Unplug all the glowplugs, and touch the other end of the testlight to the glowplug terminal. If the testlight lights up, then that glowplug is good. If it doesn't light up, then that glowplug is bad.
Get a testlight and hook one end to the battery +. Unplug all the glowplugs, and touch the other end of the testlight to the glowplug terminal. If the testlight lights up, then that glowplug is good. If it doesn't light up, then that glowplug is bad.
Senior User
Joined: Feb 2007
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From: Denair, CA
Yep, do just as Franklin says. If you do have any bad GP's then replace them with only Motorcraft/Beru. Others have a tendency to swell up when they burn out. I believe you need Motorcraft ZD-1A's for your application.
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Joined: May 2001
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From: washington
They are correct, do not use any other plug besides the motorcraft. I found that Autozone carries the motorcraft plugs. Other brands have been known to swell and break off upon removal, causing you to have to remove the head!
another way besides a test light is to hook up a positive lead to the battery and arch the lead to the top of the plug. It should have a solid arch. I've found that this gives me a solid reading better than the test light. Weak arch means plug is on it's way out...
another way besides a test light is to hook up a positive lead to the battery and arch the lead to the top of the plug. It should have a solid arch. I've found that this gives me a solid reading better than the test light. Weak arch means plug is on it's way out...
