Glow Plug Resistor Bypass on 3L Engine (1 Viewer)

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Hey guys - Not sure if this is the right section to post. I am looking to relay the glow plugs via a push button on the 3L engine of my Hiace. The glow plug resistor seems to be faulty and has sparks coming out of it when I start the engine. My buddy who has a Delica had the same problem and opted to do the bypass. Has anyone done this on the 3L motor? If so, any pointers, tips on pitfalls to avoid would be appreciated.
 
@NickPapagiorgio , first I would not recommend a push button (because a few have forgotten it was pushed in) and have burned up their glow plugs inside the head/cylinder due to some distraction.

This is a pretty straight forward modification. Some people call it a "Wilson Switch"... Basically, go get a FORD starter relay (that some folks call a starter solenoid) from the salvage yard or NAPA or wherever. Get a Painless switch that is spring loaded to the OFF Position (Momentary Switch; Part#80501). Wire this up on its own circuit. Works Fine & Lasts a long time. You'll be glad you did it.
 
Thanks @Dprio34 ! I suck at wiring and electrical stuff in general. Just to confirm how this is going to work:

1) I use the fusible link on the battery and connect it to the starter solenoid/relay
2) I connect another wire from the relay to the buss bar
3)Ground the relay
4) Connect another from the relay through the firewall onto the momentary switch (an tap an interior light to power the momentary switch?)
5) remove the fuse for the glow and remove resistor

Am I missing anything critical? Thanks again for the help!
 
@NickPapagiorgio, pretty much yes to all of the above. Here is a diagram I stole from someone else. Starter Relay body grounds to the wheel well or wherever you mount it. Just sand off some paint from the body to get a good ground. Just by-pass the entire super-glow system. Your left finger will control everything now. About a 4 second hold on the Intermittent switch should do it on all but the coldest days. Then I do about (2) 4 second holds about 30 seconds apart.

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Bumping this back up. Everything was working pretty well - that is until the temp dropped. Tried to crank it this morning - I must've held the switch for about 20 seconds but no dice. I'm assuming it's a matter of holding it in longer? But at the same time, I don't want to fry the glow plugs. I know there is voltage on the relay since it fired up yesteday, though it was warmer. How long do ya'll hold the switch for on cold days?
 
I do a 3-4 Mississippi count once between 40-70 F. Always starts. Above 70F, I never glow. Below 40F, I do 4-5 Mississippi crank....if nothing, I do another 5 Mississippi and it always starts on the second try. But it never gets below 25 F here where I live...beyond that, the Canadians should know better on their manual count.

Edit: I think 20 seconds may be a bit too long. I seem to vaguely remember reading something about the super glow system...intermittently sending voltage to to the bar, and 20 seconds seems to be too long IIRC.

Edit: Here is the page referencing the timer to the glow plug system as it relates to Water Temp or OAT on a cold engine.

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thanks for this. Yeah, I heard that before as well that 20 seconds is too long. Do you wait to hear the click from the relay before you crank it?
 
I start counting when I hear the click from the starter relay. Yes. If it aint clicking, the count doesn’t matter. Something else is array.

If you used a Ford Sarter Relay, sand a bit of paint off of the wheel well or where you bolted it too. That is where it grounds. That could be the issue if you don’t hear a click.
 
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Did you change out the glow plugs when you went to the Wilson Switch? The typical SuperGlow system has lower voltage plugs than a manual system.
 
The voltage of the glow plugs, could be an issue... But can't really speak to it. I left the same stock glow plugs in mine, and I have not had an issue. You can confirm it was running fine/starting fine prior to the fall weather?

Just to confirm, is the starter relay, "clicking"?

After you heat the plugs for 4-5 seconds? ...You are cranking, and nothing....how many chances have you given it?

Are you sure fuel is getting to the Injector?

Edit: Is there a EGR system on that motor? If there is, probably it's better to take it off. My glow plug holes where totally disgusting & packed with tar & soot when I got my JDM motor. I used a 5.56 barrel bore brush to clean them out. May be worth a try...But first I would test the voltage on the glow rail. Second, the condition of glow plugs and clean the glow plug holes with a bore brush.
 
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The voltage of the glow plugs, could be an issue... But can't really speak to it. I left the same stock glow plugs in mine, and I have not had an issue. You can confirm it was running fine/starting fine prior to the fall weather?

Just to confirm, is the starter relay, "clicking"?

After you heat the plugs for 4-5 seconds? ...You are cranking, and nothing....how many chances have you given it?

Are you sure fuel is getting to the Injector?

Yes, it ran and started up fine yesterday at around 70 degree weather. It can hear an audible click. One thing to note though is that the click only comes after at least 10 seconds of holding the momentary switch down, then after the click, I wait another 10 seconds (20 seconds total). I give it around 3-4 tries max for fear of flooding the system
 
That is definitely weird. The moment I hit the switch, you hear "click". Again, Immediately you should hear a click.
I would suspect the switch or relay, not the glow plugs, if this is the case.

Sounds like an easy fix. From what you describe, I would start at the ground of the relay, or at the wiring at the switch in the cabin, not the glow plugs.
 
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In the normal SuperGlow system there are two Glow Plug relays: the main relay, which gives full voltage to the bus bar, and the secondary or afterglow relay which sends voltage through a resistance strap that steps down the voltage.

The main relay is used at startup and is controlled by the timer module (which also takes input from a water temperature sensor); the secondary relay (also controlled by the timer module) is meant to be on during the initial run phase of the engine while it warms up to promote a smoother running engine and (I believe) to reduce emissions.

If you setup your manual switch to engage one or the other of these relays, it’s important to know which one you used.

If you setup a completely different/new relay and wired it according the diagram provided above by @Dprio34 you would want to ensure your plugs are 10.5V, otherwise you’re likely to burn through the lower voltage plugs quickly.
 
I should mention that my experience is with a SuperGlow system in a 2H (1983 HJ47), so although there is much commonality among the various SuperGlow systems, it is possible that there are important differences between the 3L and 2H systems of which I’m unaware.
 

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