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  #1  
Old 05-06-2012, 08:42 PM
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Question Glow plug relay: the opposite problem.

I did a bit of research here and I found that people get too little glow plug time on their relays, especially in cold weather. I have the opposite problem. Mine stays on well after 10 minutes of driving the car and it eventually killed my battery, so I had to buy a new one. I've checked out prices out there for a relay and since I just purchased a rebuilt tranny, I'm kind of not wanting to shell out that kind of money right now, especially since we have a little baby girl coming our way and we've put enough $ on the car lately. So I thought that I'd maybe just wire up a switch to the cabin and switch it on and off at will; would that hurt things? I saw the override switch a certain website out there sells, but since mine just stays on forever I thought a cut-off switch would be just cheaper and easier to install; is there anything I should know before I try this?

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Old 05-06-2012, 09:02 PM
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looks like new they're a tad over $100, but if $30-40 is in your price range, theres a couple up on the auction site right now
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Old 05-06-2012, 09:15 PM
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A Ford starter relay and a momentary switch is a pretty inexpensive alternative and the timer God designed in your head is pretty reliable.l
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  #4  
Old 05-06-2012, 09:37 PM
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i got an afterglow relay from ebay germany; was new and only like $40 shipped, but that was last year before they stopped making them
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Old 05-06-2012, 11:01 PM
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Quote:
Originally Posted by kerry View Post
A Ford starter relay and a momentary switch is a pretty inexpensive alternative and the timer God designed in your head is pretty reliable.l
X2.

And, you can use afterglow if you so desire on a very cold day.
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Old 05-06-2012, 11:21 PM
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Thank you, gentlemen, for your valuable input. Sleepstar, the one I got is pretty recent and I got it af Fleabay... I don't want to go that way again. Shadetree, that's a pity...
Kerry and Brian, how about just adding a switch to the wire that comes from the ignition? Run a wire inside the car and just flip it on or off? Would that hurt the current setup?
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Old 05-06-2012, 11:32 PM
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Originally Posted by cirrusman View Post
Kerry and Brian, how about just adding a switch to the wire that comes from the ignition? Run a wire inside the car and just flip it on or off? Would that hurt the current setup?
Are you referring to the violet wire that extends from the ignition to the glow plug relay?

If so, you'd still need a functioning glow plug relay for such a switch to work. This switch could work to allow the driver to control the time of engagement of the relay, however, the timer in the relay would override the new switch.
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Old 05-06-2012, 11:35 PM
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Have you done any trouble shooting to make sure it is a bad glow plug relay and not external issues? If the glow plug relay is indeed bad, you can open it up and run wires from the relay coil to a switch to manually control it. Much cleaner, less work and less cost than using a Ford starter relay.

I never liked those Ford starter relays. They are poorly made, makes a big clunk when switched on, not sealed well - moisture get in and they stop working after a few years.
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Old 05-06-2012, 11:38 PM
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Originally Posted by cirrusman View Post
...how about just adding a switch to the wire that comes from the ignition? Run a wire inside the car and just flip it on or off? Would that hurt the current setup?
Depending on what has failed in the timer unit, that may or may not work. It could turn out to be just like installing a landing gear switch in a Cirrus.
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Old 05-06-2012, 11:40 PM
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Originally Posted by Brian Carlton View Post
Are you referring to the violet wire that extends from the ignition to the glow plug relay?
That would be the wrong wire to switch. The switch would need to go in the wire that is hot in RUN. Opening that circuit would (in theory) have the same effect as turning the key off.
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Old 05-07-2012, 12:15 AM
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Quote:
Originally Posted by kerry View Post
A Ford starter relay and a momentary switch is a pretty inexpensive alternative and the timer God designed in your head is pretty reliable.l
That's the route I went and am very happy with the setup. It's very easy to install. Grab a solenoid at the JY - they're often right next to the battery. Take a lead off the battery for hot, and run a length of 4GA wire to the glow plugs.



To keep things looking stock, I gutted an old glow plug relay box and used the existing fuse and distribution plug so I could use the stock harness.

Here's the finished product




And here's a link to the post on how to do it - http://www.peachparts.com/shopforum/2891181-post223.html

The only thing that was tricky was, I didn't trust that my momentary switch would handle the load so I added a relay for safety. (Make sure you use a momentary switch to prevent burning out the glow plugs by forgetting to switch them off) I used a switch with a LED indicator for positive feedback of glow plug operation.

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Glow plug relay: the opposite problem.-glowplugrelay1.jpg   Glow plug relay: the opposite problem.-switch-1.jpg  
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  #12  
Old 05-07-2012, 12:16 AM
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Originally Posted by tangofox007 View Post
That would be the wrong wire to switch. The switch would need to go in the wire that is hot in RUN. Opening that circuit would (in theory) have the same effect as turning the key off.
The added switch could keep the violet wire closed for an indefinite period. The driver could open the circuit at his discretion. Obviously, the new switch would need to be in parallel with the ignition switch.
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  #13  
Old 05-07-2012, 12:26 AM
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Originally Posted by Brian Carlton View Post
The added switch could keep the violet wire closed for an indefinite period.
How does that address the problem? The OP needs to terminate the glow cycle, not extend it. It's already extended, and that's the problem. Evidently, the controller isn't paying the violet wire much mind, anyway.
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Old 05-07-2012, 12:33 AM
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Originally Posted by tangofox007 View Post
How does that address the problem? The OP needs to terminate the glow cycle, not extend it. It's already extended, and that's the problem. Evidently, the controller isn't paying the violet wire much mind, anyway.
Read post #7 and you'll understand...........or not.
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  #15  
Old 05-07-2012, 12:46 AM
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Quote:
Originally Posted by Brian Carlton View Post
...however, the timer in the relay would override the new switch.
Are you sure about that? Does the timer still function once the violet wire gets power?

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