The guessing game is a result, in part, of the same component being used in both four and five cylinder engines.

I've managed to grab spare glow-relays for my '82 240D and '84 300TD at my Pick-N-Pull. At least on my cars, they aren't identical. Haven't tested either spare but they were cheap enough. I suppose I could rig a push-button switch to do the job - so long as I didn't heat the plugs long enough to fry them. Anyone know the price of a new glow-relay?

Happy Motoring, Mark

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DrDKW

0015459832 (300TD)
0015459732 (240D)

They're about $100 for each of them...

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Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

Sounds reasonable, compared to some prices I've recently heard for W123 parts - like $800 for a heater-blower, or $1200 for an SLS-pump!

Happy Motoring, Mark

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DrDKW

For that price, looks like its time to build my own.. As long as the contacts are still good, replacing the electronics is a breeze...

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Ich liebe meine Autos!

1991 Mercedes-Benz 560SEL | Megasquirt MS3-Pro | 722.6 transmission w/ AMG paddles | Feind Motorsports Sway Bar | Stinger VIP Radar | AntiLaser Priority | PLX Wideband O2 | 150A Alternator | Cat Delete
1981 Mercedes-Benz 300SD | Blown engine, rebuilding someday...
1981 Mercedes-Benz 300SD | Rear ended, retired in garage.
2009 Yamaha AR230HO | Das Boot

Excessive speeding? It ain't excessive till I redline!

After two earlier unsuccessfull attempts, this evening I finally found a Hella pre-glow time-relay listed under 'body-electrical' on Fastlane - for $193.50.
It supercedes the earlier designs and replaces both W123 240 and 300 diesel glowplug relays.
This upgrade part operates the glowplugs for up to 3 minutes after engine startup and appears to require replacement glowplugs.

Happy Motoring, Mark

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DrDKW

I've had one of those in my 300D for about 5 years now, it works well. Just one word of caution, if you take lots of very short trips you may find the battery running down because the alternator has trouble keeping up with the post-glow demand while charging the battery. It's not an issue if you drive more than a few minutes after starting the car.

How did you arrive at that conclusion?

By reading the information posted by Fastlane for their Hella pre-glow time-relay.

Happy Motoring, Mark

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DrDKW

When my glow plug relay went out a few months ago, the dealer wanted $270 for one! I ended up buying a used working unit from the PickNPull for $12.

If that didn't work, I'd probably get a new one either from Pelican or possibly Walt (He carries the newer Hella type ones that glow a lot longer).

Packman

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83 240D - 4 speed manual - Manilla Beige
189K miles, Tachometer mod, cool wooden shift knob from PeachParts, CocoMats, Original factory paint, manual windows, manual sunroof. Starting to add AudioWrap to this car too!