-The top right pin in the Glow Plug Relay, what glow plug number does it go to?

- It reads as an open on the ohm meter. Rest are below one.

- Should I replace all or can I wait until Spring? I live in Philly.

- Car is 1987 300 SDL


Thanks

I believe there are tiny little numbers imprinted on the relay plug, next to each hole, that say what number plug. If only one is bad, you can just replace that one. I did just the No. 5 last year and did fine all winter. I had a couple go bad a month ago and just replaced all the rest since I needed to do the intake gasket anyway.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

- Thanks. I tried reading the numbers but, were too small for me!

I have it written down at home on the GP number relative to the holes on the big connector. But I am at work.

If it is the top right pin then it is either 1, 2 or 5, 6 cylinder. You can measure the resistance directly at the GP using a long probe. Just use a insulated metal wire to probe at the GP nut. I normally only change out the burnt one.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

- Thanks. Could you also check at home for the number.

- Looks like a difficult replacment job unless you take a whole lot of stuff off.

I'll check when I get home ... I'm pretty sure it'd be the same on a 124 as 126. Just to clarify, when you say top right, you mean when looking at the face of the plug, not the back, correct? I won't be home until after midnight, and it's a little dark/cold to do it in the parking lot at work.
It's a bit of a pain, lots of skinned knuckles. I probably should have written down the combination of wobbles/extensions I used, but it's different for each plug. You can do it with the intake in place ... I've got small hands which helped, I guess. You will need a deep drive 13mm socket for the plug. When you go to put the new plug in, start it by hand, not with the wrench ... I was able to fit my hand in there to do so but if you can't, use a bit of rubber hose over the back of the plug to snake it in there and gently start it. Then you can put the wrench concoction on to tighten it up.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

- Thanks, no rush.

- Standing on the driver side looking at the Relay with the cover off it is the furthest pin on the right from you.

- It has the black plastic locator for the cover next to it.

- Attaching an image.

Attached Thumbnails

 

Sounds like #1. I just replaced #4 this afternoon. Pretty easy considering. All I had to do was pop the upper throttle linkage. The front 3 are a bear with the manifold in place.

Looking at the pins in the relay with 'x' as the locating post:

x
1 2
3 4
5 6

You can't see the numbers on the connector? I can see them in the picture you posted. Man, I hope you're not younger than me

Sixto
87 300D

- Thanks. I am 71.

X
- 1 2
3 4
5 6

- Again X being the location post the open pin is #2. (Top right)

- I assume the glow plugs in the engine are numbered starting with #1 on extreme right?

On the engine, #1 is closest to the radiator, #6 is closest to the cabin.

Sixto
87 300D

Derick,

Just to be clear, you are measuring resistance between the hole (connector) in the plug (not the pin on the relay) and a good ground point, right? You keep using the term "pin" but the pins are on the relay (male), the female connector is in the plug. The wires to each of the six glow plugs run from the female connectors in the plugs. If you are measuring at the pin on the relay, you are doing it wrong.

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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 am measuring the resistance between the hole and a ground. (The feamale part of the connector)

- I used the pins as a reference as to their numbering.

- Thanks.

Sixto

- I guess the manifold has to come off to replace #2?

Thanks Derick

Just to be sure, touch a probe to the electrode of the #2 plug and check the resistance. Discount a bad wire before you remove the manifold. Of course, if it's a bad wire you'll have to remove the manifold to replace it :/

You might have the right tools and 5 knuckles on each finger to get to the plug without pulling the manifold. Certainly try first. If the manifold has to come off, consider replacing all the glow plugs. I've heard good things about Bosch, okay things about Beru, not so good things about Autolite.

Sixto
87 300D

- Thanks. I will definitely measure the resistance at the glow plug.