Glow Plug and Water Pump Question('87 300 SDL) - PeachParts Mercedes-Benz Forum

Turbopugsleylx · #1 01-12-2008, 04:34 AM

Hey guys, what does it mean when the glow plug light doesn't come on the dash prior to starting it? The glow plugs are already warm?

Also on the 300SDL '87 which is my car whats the typical life on the water pumps before they go out on them? I just got stranded cause the alternator going out, and I don't want it to happen again!

Pugs

Turbopugsleylx · #2 01-12-2008, 12:02 PM

bump

probear · #3 01-12-2008, 12:18 PM

When you say the glow plug light doesn't come on, are you meaning all the time?
Mine always comes on. The first thing to check are the glow plugs. If the #1 plug is out, the light will not come on, and if any 2 of the remaining 5 are out, then the light will not come on either. You can check the resistance from the glow plug relay located in the front left of the engine compartment. The plug is numbered and it's quick and easy to eliminate that as a problem. You should get .7 +/- Ohm on each plug.
The next thing to check is the fuse in the same relay. Some will just develop a hair line break and at a glance, it looks OK, but will not work.

#4 01-12-2008, 01:05 PM

Is there something wrong if you hardly ever have to wait the glow plug light? You just turn the switch on entry and it fires right off.

Turbopugsleylx · #5 01-12-2008, 01:13 PM

thats has happened as well good question...

grindMARC · #6 01-14-2008, 05:03 PM

Quote:

Originally Posted by probear

When you say the glow plug light doesn't come on, are you meaning all the time?
Mine always comes on. The first thing to check are the glow plugs. If the #1 plug is out, the light will not come on, and if any 2 of the remaining 5 are out, then the light will not come on either. You can check the resistance from the glow plug relay located in the front left of the engine compartment. The plug is numbered and it's quick and easy to eliminate that as a problem. You should get .7 +/- Ohm on each plug.
The next thing to check is the fuse in the same relay. Some will just develop a hair line break and at a glance, it looks OK, but will not work.

My #1 plug is testing infinity for ohms (toast). The rest check out fine. When you say that the glow plug light will not come on if #1 is not working -- does that mean that the glow cycle is not happening at all? And that I should avoid starting the car until I get this plug replaced?