Hi There,

I had some grief registering, but all good now.

I swapped an OM603 into my 92 Sierra 4x4, using an adapter plate to the stock 700r4, retaining the GM running gear, ecm etc.

The truck is on the road and working fairly well, though I do need to put a diesel torque converter into it as the stall speed is too high.

My current question is about the glow plugs. I initially had them wired to a push button, this was slightly annoying. So then I just used the stock relay using the default 30 second timer, but I did not hook up the starter wire (that shuts them off when you turn the engine over). This worked great as I am in Canada and it’s hovering around zero. But it seems I have killed four of the six glow plugs, I assume they were old but I wasn’t having starting issues initially after the swap. What I am getting at is, what is an acceptable amount of time to run the stock glow plugs for? Is 30 seconds too long? I would prefer to have them run for a bit after the engine is started for better cold starting.

Any help is appreciated

The amount of glow time is directly related to water jacket temperature. From memory at minus 30 the glow time is 20 seconds, after glow about 90 seconds but at 8 volts the glow was 12 volts. That's from 92 602 so should be about the same. At 0 degs C glow time is around 10 seconds after glow 30 seconds. The after glow is to reduce smoking.

Where in Canada are you?

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92 e300d2.5t
01 e320
05 cdi
85 chev c10

Sorry I forgot to mention the engine is out of an 1987 300 TD.

I did not hook up the Mercedes ecm as I did not think it was required and I was under the assumption that the glow plug relay was default 30 seconds and only interrupted when you bumped the starter? Is this not correct? If so I would add the ecm.

I am located in Revelstoke BC!

The GP relay operates on its own no need for the ECU. The temperature sensor is located on the front passenger side close to bottom of the valve cover just beside the chain tensioner. That should feed directly into the relay not having it connected will default to the max time duration. That is assuming it is the original relay?

__________________
92 e300d2.5t
01 e320
05 cdi
85 chev c10

I know exactly what sensor you are referring to. Thank you so much for that advice! I assume it is advisable to still hook up the wire to the starter to turn off the GP's when the starter is energized?

I did order all new glow plugs and it is pretty obvious I had GP issues from day one, but I was not familiar with this engine and I imagine cold starting will drastically improve.

Thank you again and will update after the new GP's are installed

To clarify the wiring on my GP relay. The four prong plug to be specific. I have two wires not hooked up at the moment. A black wires and a purple wire. I believe the purple wire is intended for starter? The black is for the temperature sensor? Please see pic. What is the black sheathed wire with the male single prong in the second picture for?

Please keep in mind I did not pull this motor/wiring harness, just made it work and I am improving it as needed.

Attached Thumbnails

   

Cheers

Attached Files

24071900.pdf (60.1 KB, 34 views)

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92 e300d2.5t
01 e320
05 cdi
85 chev c10