Glow plug system not working and engine little tough to start, even here in FL. What do I need to check and where is the glow plug relay on the ‘87?

thanks
Bill

Go to dieselgiant.com and follow the troubleshooting steps that are VERY well documented. You'll need a voltmeter.

What‘s the best way to change out the glow plugs on the ‘87 300SDL, to remove the intake manifold, or work around it? If it is to remove the intake, are there any tricks I should know and are there any other jobs I should do once it’s off?

Thanks
Bill

If you remove the manifold, have extral injector line clips handy to repair any that are broken or missing.

My method of choice is to remove the cruise control actuator. Leave the manifold in place.

Sixto
87 300D

Is the light coming on? If not here is what you do, before tearing into it.

Open the hood and look behind the drivers headlight. You will see a black box in front of the ABS pump. Pull the cover off said box, the GP strip fuse is located inside. I think its an 80 amp strip fuse. They break and fail with age, since they cost almost nothing its good practice to buy a few and carry a spare in your glove box.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

When the system fails suddenly and completely, the fuse is the most likely culprit.

Yep 6 GP's don't all die at the same time.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Now why would you carry a spare of something that lasts 20 years?

Speaking of which, has anyone heard from P E H?

Sixto
87 300D

No now that you mention it. I hope he is doing allright.

He will never come to any of our GTG's, even when they are pretty close to him.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Getting power to the relay and through the fuse based on meter readings. However, the six ohm tests at the relay sockets looked bad: 10.0, 10.0, 01.6, 17.3, 11.1 and 01.7. So, assume it’s time to change out the glow plugs?

Any other opinions on whether to remove intake manifold or work around it? Also, if I work around IM, assume need to pry off linkage (not sure what it is) at both connection balls that blocks access to plugs 3-6? Do I also need to take off all injection lines which would make it easier to get to plugs 1 and 2? Any one know off hand socket size I’ll need for the plugs? Any other tips?

Thanks
Bill

Yank the intake, its not that hard.

Now is a good chance to clean it up because its going to be full of EGR tar.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I recommend removing the intake manifold. If you have not defeated EGR it will be filthy inside, a good opportunity to clean it and a good reminder of why you need to defeat EGR. Looks like you have 4 bad glow plugs, you might as well replace all six as they are only about $10 each for your car.

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

Get a stiff small toilet or pipe brush, and a cheap container that is large enough to sumerge the manifold in. Throw a few gallons of kerosene or B100 in and let it soak, use the brush to remove the crud.

Than use a plate to block the EGR for testing.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

X2

Jeremy is right on. Clean the crossover, intake, etc and disable the EGR.

__________________
1987 300TD 309, xxx 2.8.2014 10,000 mile OCI


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