Glow plug wiring RD28T

[Ludde]

Hi guys,

Im trying to help my father with some hot starting issues on his 1998 GU. I think the engine is called RD28T. It's a inline 6, 2.8L Turbo Diesel with the intercooler mounted above the valve cover.

However, we have tried with the cover on the pump, and that made the car run a lot better, but did'nt help when it comes to the hot starting issues.

Today we checked some more, and it seems like the relay for the glow plugs doesnt connect from time to time when the engine is hot. I've been seaching this site and as far as I understand it this engine has a dual glow system? The problem is that I only found one glow relay... Could it be a dual system with only one relay? But my biggest question is if anyone has a wiring diagram for the glow system on this engine? I tried to search for it, but could'nt find what I was looking for.

Is someone could help me with this or point me in the right direction it would be great!

And sorry for my bad english, Im a stupid Swede...

Best Regards,
Ludde

[Yendor]

Hi Ludde,

Welcome to the forum, you will need to go over to the introductions section and post an intro about yourself, it's just something we request of all new members.

I don't think your hot starting problem will be caused by the glow plugs, here is the info you requested.

Cheers Rodney

[Ludde]

Thank you!

Introduction written! Was to fast to search for help, so I missed that part of the forum...

It sounds a little strange to me to that the glow plugs would cause the problem. But we gave it a little shower with "start gas" (I dont know if that's the correct word in english) and on that it starts perfectly and continues to run well. So to me it seems like the thing that is missing in the starting moment is the heat from the plugs as it runs really nice and smooth on the diesel after the "start gas" is gone. We also made some tests with the engine cold, and it seems like the relay does'nt connect every time, even tho the indicator for the glowing is lid up in the dash.

Edit: Could open the pics, just computer issues....

Cheers Ludde

[Petit caillou]

Hello Ludde,

Normally you have two kinds of candles on the warm-RD28T, is that your patrol smoke when starting the engine.

You must provide sound if your relay switches after preheating

- Insert the key
- Contact (indicator lights glow a few seconds and then goes off)
- Relay slap in the engine compartment,
- Start.

Regards
Petit caillou.

[Ludde]

One question about a manual switch for the glowing...

If we cut the LG/B cable between the ECM and the glow relay and install a switch that gives the relay ground, instead of recieveing the ground from the ECM, will this cause any other issues?
If I just leave the ECM-end of the LG/B cable "hanging".

I know the manual switch would be able to make the glow plugs getting current even with the ignition off, but will we have any other problems? I red something about that the tacho would'nt work if you throw the glow controller away, but I guess this is in cases where you have a separate glow controller and you don't recive the ground to the glow relay from the ECM?

[Yendor]

One question about a manual switch for the glowing...

If we cut the LG/B cable between the ECM and the glow relay and install a switch that gives the relay ground, instead of recieveing the ground from the ECM, will this cause any other issues?
As far as I can see it shouldn't cause any other problems doing this.



I know the manual switch would be able to make the glow plugs getting current even with the ignition off, but will we have any other problems? I red something about that the tacho would'nt work if you throw the glow controller away, but I guess this is in cases where you have a separate glow controller and you don't recive the ground to the glow relay from the ECM?


It's only the 2.8 GQs that the tacho works through the glow plug controller, the 2.8 GUs have a totally different system, the glow plugs are controlled by the engine ECM.

I would make sure you use a good quality momentary push button switch and that the wire you run from the relay to the switch is well insulated and has no chance of shorting to ground.

You can also change the switching side of the relay from battery to ignition (pin 1 at the relay)

[Ludde]

The manual switch sovled the starting issues, thanks guys!

We are thinking about changing the glow plug since we saw that it is the stock plugs from 1998 that is still mounted. The problem is when the guys in the part store uses the chassienumber to get the spec. for the plugs the computer says that it is the dual stage plugs like in the GQ that is mounted. But it is'nt, it's the 11v as the engine is a RD28ETi (GU).

Anyone know either the Nissan part no for these plugs, or part no for some aftermarket plugs like Bosch, Beru or NGK?