GLow Plug Relay

[stugots1982]

Hey everyone,

Wondering if anyone may have a line on a glow plug relay? The one that sits above the air can under the driver. Its not the super fast type with 2 relays, its the slower type with the single relay. I had an issue a few weeks back with a bit of a "fire" in my glow plug relay bypass switch and now im not getting any clicks what so ever from the relay. When I had the issue I was still getting the original first click but I believe I may have banged the relay a little hard when checking things out and removing the bypass or there may have been some residual damage that caused the relay to stick when everything cooled down after the mad rush of current.

Cheers

Stu

[FalcoColumbarius]

So not stock?

[Growlerbearnz]

Falco has a point: your van would have originally had the super quick two-stage glow plugs. Usually when people convert to manual control they leave both relays in place- but it sounds like you're down to one.

Factory part number is MD074991, but they're CD$100 from Amayama. Since it's already been modified, I'd fit a generic relay.

Generic glow plug relays aren't difficult to find. https://www.google.com/webhp?sourceid=c ... g+solenoid

[stugots1982]

interesting because when I was doing research on my glow plug system on here there seemed to be 2 different fits for the glow plug system according to the guy with the mystery machine. He said some had the super quick and others didn't( those only had the one relay). There doesn't seem to be a spot where the previous one would have been fitted. It looks like original fit with just the one relay. ill see what I can find for generic relays I guess. Cheers
Stu

[stugots1982]

OK so pardon my ignorance but am I able to fit any generic glow plug relay? I assume they all work the same since a glow plug is fairly simple and you just want them to come on and turn off before they burn up or do I need to be concerned with specifics regarding on time and what not? Since they all seem to have all the same basic connections I assume so? Cheers

[Growlerbearnz]

What's the chassis number of your Delica? P25W and P35W from 1989 up to 1994(ish) should have the super-quick glow system. P25/35V had the single stage, as did anything after 1994(ish). It's possible low-spec P25/35W had the single-stage glow plugs too. Looking up your chassis number would help.

Can you take a picture of the firewall where the glow plug relay is? It's tricky to get to, I know, being tucked up behind the air filter. For reference, a super-quick system looks like this:

CRW_1754.jpg (45.45 KiB) Viewed 11579 times

(1=glow plug relay, 2=other glow plug relay, 3=starter motor relay, ?=dropping resistor)

Am I correct in reading that you have a glow plug bypass/manual switch *and* the original ECU? It's possible that your ECU no longer functions correctly; I can imagine a couple of ways of wiring up the manual switch that would fry the ECU. And that's without an electrical fire to mess things up.

I'd try applying 12V directly to the coil terminal of your existing relay (terminals B or E in the picture above) and see if they click.

At the risk of invoking Murphy's Law, any glow plug relay will work. I say this because our engines are quite small and the glow plugs relatively weak, and almost any other diesel engine glow plug will be rated to run more cylinders at a higher power. A relay that's too big shouldn't do any harm.

[stugots1982]

Yeah ive been up in there after my little fire. That is not the set up I have. Currently I have a 1991 Super Exceed. Im not too sure where to find the chasis number, is it in the VIN? Here is what I have at the moment. ( I added the pic but its not popping up) The "bypass" was wired to the HOT terminal on the relay, then up to the switch in the cab. Then on the other side of the switch the wire ran back into the relay and spliced into the green wire I assume that runs to the glow plugs so that when the switch is made the glow plugs are getting voltage. After the smoke got let out of the wire the relay I noticed was still giving me the initial first click, its been a while and I don't recall getting a second click after the heat, nor do I particularly remember one prior to this either. I assume however the relay was working or possibly not and that's why the bypass was installed. Regardless, I know it was giving me the first click right after this. Now I don't hear any click at all.

[stugots1982]

Im thinking at this point, possibly just replacing with a generic glow plug relay should solve my issue? As for the ECU I wasn't actually able to see it in the pillar but im not sure how high up it was

[Growlerbearnz]

Ok, I see what they've done. It's a fairly standard setup. When power is applied to the thin green wire it turns the relay on. Power then flows out the cold side (the other large black/red stripe wire) to the glow plugs. It looks like the wire to the manual switch has rubbed through and shorted out somewhere. If you just remove the blue connector and the burnt wire you should be back to standard.

Try unplugging the green wire from its spade terminal on the relay, and applying 12V to the spade. (while the relay is bolted to the firewall). That should make the relay click- if it doesn't click, you need a new relay. If it clicks, then the fault is in the power supply to the green wire.

Still interesting that yours is a '91 super exceed with the single-stage glow plugs. The brackets are all there for the rest of the system, but they don't seem to have been ever used. Unusual. Chassis number is under a plastic cover by the drivers seat:

Identification004.jpg (43.16 KiB) Viewed 11572 times

[stugots1982]

Yea ok that's pretty much bang on what happened. So where would the small green wire originate? at the ECU? Thanks for all your time. Ill try feeding the 12v to the relay when I get a chance in the next few days.

[Growlerbearnz]

You've got it. The ECU powers the green wire. Usually.

The blue scotchlok connector is evil, BTW. They're quick and easy, but they damage the insulation and create a fatigue point on the wire. If you remove the connector It's a good idea to wrap the green wire in a bit of insulating tape. If you need to tap into the green wire again, consider a proper twisted and soldered joint.

[stugots1982]

yea i totally figured that when i seen the connector that was used for the splice. not to mention that area is essentially open to the outside.

[jelbon]

I bypassed my entire system by using 11 volt glow plugs, a ford starter relay and a momentary switch on the dash to energize the relay.
Wired direct from the battery through a 50 amp circuit breaker with 10 gauge wire to the relay and glow plugs and 16 guage wire from the relay to momentary switch.
Just hit the momentary switch for 10 seconds and then hit the starter.
Works fine.

[stugots1982]

that sounds similar to what i had in the van when i got it. if all else fails i can reinstall another bypass switch myself.

[stugots1982]

so now that my fuel issues are beyond my abilities it is going to cca next week. on that note back to another issue. my glow system. now that the weather is getting cooler my older issue is starting to become an issie ive tested my relay and its toast. im just wondering if anyone knows the current draw of the glow system on the relay. ive found a relay from lordco for 80 bucks but im also looking st CT and they jave 40amp relays for under 10 bucks just not sure if 40 amps will be enough. Anyone have a clue what the draw is?