Pencil-type plug, or the earlier type?

Pencil-type is only supposed to start at around 15 amps, and then drop below 8 amps after 10-20 seconds.

The earlier type did NOT consume 12v, so if you applied 12v to an earlier type plug, that is the behavior I would expect.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

I can definitely confirm that no purple wire=afterglow on the 617 turbo. Just curious how it's different on an N/A and why.

-Rog

My 84 300D has the pencil type glow Plugs. What I said is what I observed when I did the test.
The Glow Plugs did pull about 16 amps when they were fully hot.


If you apply 12 volts to a single filament/loop type Glow Plug it will it will quickly burn the filament/loop. I hope no one tries that.

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84 300D, 82 Volvo 244Gl Diesel

I don't believe that it results in an afterglow either but I have never tested so I don't know and is why I don't challenge people who say it does cause an after glow.


I am guessing that disconnecting the Purple Wire and cranking the Engine causes an error and that causes the Glow Plug Light to go on and people think that they are getting afterglow. But, I have no proof.


Except for the ones that pass me in traffic or might be in a parking lot I have not even seen under the hood of the non-turboed 300Ds.
What ever knowledge I have acquired about them comes from reading on this forum or in the Service Manual.

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84 300D, 82 Volvo 244Gl Diesel

No extra light, in fact the light works as normal, and they definitely glow for 30 seconds (defaults to the timer rather than being interrupted by the starter). Super easy to confirm for yourself, you just pop the connector open and the wire can be slid out (and reconnected at any time). I happen to leave mine like that, but I've contemplated wiring it to a switch on top of the relay box so there will be a winter and a summer setting.

-Rog

Have bypassed all factory fuel lines, connected fuel lines directly to a bottle of new diesel, that goes through a new primary filter to the IP. Did not replace the secondary filter yet. But have fuel making the complete circuit back to the temporary fuel tank. Car has not been licensed since 2002, so guessing engine has not been ran for a while. Still waiting on key from MB dealer

Installed new starter, a real pain, with the steering wheel locked. New starter spins engine over much faster, and engine is on the verge of starting. Idle adj cable is rusted tight, so not quite sure on where to set the idle for the first start. Will keep plugging along.

Its running!!!!!!

Engine actually sounds really good. Ran it until the thermostat opened up, do not want to run it to long until I can use the dash gauges. Hopefully the new key arrives, and works.

New key arrived today, it does not work. Looks like idiot PO tryed jimmying it with a screwdriver.

What is the best way to bust steering lock?? Bottle jack, and 2X4?? all suggestions welcome. Heading back to town now to get a push button SW, a toggle SW, and a vacuum valve.

1984 190d - lost key

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

Researched how to remove steering lock, during rainstorm. Removed instrument cluster, steering wheel, 2 13mm nuts holding steering column up, and used dremmel tool to grind off the lock pawl. Had to pry, chip wires from plug at the back of the ignition sw, since I could not turn tumbler to any other positions. Now need to figure out wires I need to wire to the toggle switch. Do not have any good schematics so need some help here. Have figured out a couple of the wires, I think

2 solid red wires 12V hot at all times?
1 V/W goes to neutral safety sw
1 R/W ??
1 R/G ??
1 G/W ??
1 R/B goes to glow plug relay?

Wiring harness also has a 2 pin connector with a Red, and a R/G wire in it, any idea where it goes???

This video should help you out if the wires came out of the switch
https://www.youtube.com/watch?v=5sIEQgM6gCQ

And here is the wiring diagram: https://www.startekinfo.com/StarTek/outside/12265/disc_2/program/ETM/81_300.pdf

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78 W116 300SD 'Desert Rose' new as of 01/26/2014
79 W116 300SD 'Stormcloud' RIP 04/11/2022

The Lock Tumbler can be drilled out and there is a pin on the steering Colum Lock that can be drilled or groud off.

On a 1982 you might be able to unscrew the Ignition Switch that is at the bottom of the Steering Colump lock and pull it out.
I am not sure when they started doing it but the by 1984 the aluminum sield on the ignition swith enclosed it more and there is a T pice inside that keeps you from easily pulling out the Ignition Switch.

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84 300D, 82 Volvo 244Gl Diesel

The Pre-glow wire is Red/Black on Terminal #1 of the glow plug relay. The purple wire is the cranking input on Terminal #2 and is tied to the starter switch.

The idea is that when the engine is cranked, the signal to the starter motor will cancel the glow plug cycle turning off the glow plugs. Lifting the purple wire will cause the glow plug relay to run for its entire timed sequence. Supposed to be 30-40 seconds, but with drifting capacitor tolerances can be as little as 5-10 seconds (I have a thread where I fixed this issue in my GP Relay). Lifting the purple wire DOES cause the GP relay to run its full timed cycle. Not good on your glowplugs though.

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Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Another old Coupe being saved ! .

Before trying to start it you should adjust the valves, it's a rare thing that some won't be tight and this causes hard starting along with a host of other maladies .

Keep us posted please .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Any proof out there for this? I haven't found any. The later cars had afterglow built in, so I'm skeptical that it wears them out significantly. I've had the same glow plugs for six years, roughly half of that with the purple wire disconnected and I have no complaints. I've seen people with a stock setup talk about replacing their glow plugs constantly, so I would be surprised if it mattered at all how long they glow. They live in a pretty harsh environment regardless.

Still, one anecdote doesn't constitute proof so I don't claim it as a fact.

-Rog