Pics: Inside a glow plug relay - PeachParts Mercedes-Benz Forum

JamesDean · #1 01-16-2010, 01:59 AM

Hello everyone,

I dont think I ever recall seeing any pics of what was inside a glow plug relay box so as I've decided to snap a few pics for anyone who's interested in taking a look:

This box is part number: 001 545 98 32
It is for a 5-cyl 617

This one came out of my green SD as part of a diagnostic and was replaced with a known working one from my gold SD.

After fixing the issue with the green SD, I've tried to reinstall this one into my gold SD.

It appears to be dead. No cluster light. No voltage at glow plugs.

Correction: It works, just needed some cleaning on the terminals.

Diesel911 · #2 01-16-2010, 03:01 AM

Thanks.

pawoSD · #3 01-16-2010, 11:54 AM

I took one apart a couple months ago that was malfunctioning (staying on)....nothing looked wrong physically, but I did not waste much time on it as I had a good used one on the shelf.

okyoureabeast · #4 01-16-2010, 12:02 PM

What I love most about my car is the fact that the radio is probably the most advanced electronic gadget in the car.

I love how you can follow solder paths on the board. Try doing that with a modern computer!

TnBob · #5 01-16-2010, 04:15 PM

An emery board cut down the center to make it much thinner is a great tool to clean those contacts with too. The thinner the better as long as the contacts dont tear it.

When your thru sanding the contacts a quick wipe with rubbing alcohol is a good thing to do to insure everything is smooth and clean.

Codifex Maximus · #6 01-16-2010, 04:38 PM

Back when I used to run a Video Game arcade, we'd use a dollar bill to clean contacts for joysticks and buttons. Very low abrasion and high utility as far as cleaning electrical contacts. Might be useful for the final buff.

#7 01-16-2010, 05:32 PM

Quote:

Originally Posted by Codifex Maximus

Back when I used to run a Video Game arcade, we'd use a dollar bill to clean contacts for joysticks and buttons. Very low abrasion and high utility as far as cleaning electrical contacts. Might be useful for the final buff.

Also useful for cleaning valves on musical instruments, rolling papers are good too.

charmalu · #8 01-16-2010, 06:57 PM

with the advancements in electronics today, the new relays should have
smaller components and/or less of them to do the same job.

the printed circuit board, looks like some we used when I worked for
Sylvania back in 68.

Charlie

scottmcphee · #9 01-17-2010, 01:58 AM

The biggest advancement nowadays would be to get rid of those in-line current sensing coils, and have Hall-effect type current sensors just mounted next to the high-amp lines. And, there would be one per glow plug, none of this "first one" or "last one" or "something in between" guessing game.

tangofox007 · #10 01-17-2010, 11:42 AM

Quote:

Originally Posted by scottmcphee

The biggest advancement nowadays would be to get rid of those in-line current sensing coils, and have Hall-effect type current sensors just mounted next to the high-amp lines. And, there would be one per glow plug, none of this "first one" or "last one" or "something in between" guessing game.

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

Mark DiSilvestro · #11 01-17-2010, 12:58 PM

Quote:

Originally Posted by tangofox007

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

JamesDean · #12 01-17-2010, 01:38 PM

Quote:

Originally Posted by Mark DiSilvestro

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

0015459832 (300TD)
0015459732 (240D)

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

Mark DiSilvestro · #13 01-17-2010, 01:57 PM

Quote:

Originally Posted by JamesDean

0015459832 (300TD)
0015459732 (240D)

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

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

300SD81 · #14 01-17-2010, 02:45 PM

Quote:

Originally Posted by JamesDean

0015459832 (300TD)
0015459732 (240D)

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

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...

Mark DiSilvestro · #15 01-17-2010, 09:29 PM

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