keimini

I have a 1985 300d. The last 300 I had was an 83 and the glow plug light stayed on for about 8-10 sec. It would not start well unless I let the light go out before cranking.

Well this new one. lol. will start just like a gas car without any glowplug time at all. if I do let the light turn on and off by its self then the light only stays on for about 3 seconds.

The car is very low on power when cold untill the turbo kicks in or untill it warms up. By the way what is warmed up for this car. the last one ran at the mark above 80 c. this one runs at 80 c or less.

Thanks for your input
Keith

240D 3.0T

Glowplugs should last 2-10 years.

The car should run at or slightly above 80*C. If its less then change your thermostat and temperature sensor/sender in the head.

keimini

Thanks for the info. What I should have asked is how long is the light supposed to stay on for. or

How long are the glow plugs supposed to glow for prior to starting the car?

Thanks.
Keith

240D 3.0T

The light turns on for 2-5 seconds depending on how warm the engine/air is and the glowplugs will keep working for 30 seconds or until the starter is used. The light is only a suggestion, not how long they are actually glowing.

Polar Bear

If one of them is bad sometimes the glow plug light will not illuminate at all. I think it has to be #1, but I can't recall it has been so long.

whoover

I had an '83 SD with the same engine, I think. It was a while ago, but I don't think they even had a light in the W126. They just told you to wait a few seconds.

Last time I was in Europe I rented a modern turbo-diesel. You don't even pause for a second. It's exactly like starting a gas engine. And the grunt is unbelievable.

Polar Bear

It'd be nice if they had them here in the W221!

tanktube67

All depends on the engine temperature; if your glow plugs are old you may want to cycle it two times, if the plugs are old install new ones.

tanktube67

low power when engine is cold, it could be the engine is not burning the fuel correctly is normal on old cars

Berde

W126s they have a light, as mine takes about two seconds. I always wait for the light to turn off since I was told it will take life away form the glow plugs.

Last time I was in Europe I rented a modern turbo-diesel (A class) and not only was it fast but gave me like 48 MPG. Wife and I went from Frankfurt to Baumholder to Paris and back with three fill ups. Is about the size of a Pontiac Vibe/Toyota Matrix, but MPG and torque way better...It was a good looking model too, looked like a mini R class.

mike-81-240D

Yuck R class

240D 3.0T

You were lied to.

nebojsa33

glow plug light was intermittent, now it is out, last week i had to turn the key about 2 or 3 times and it would show the glow plug light, now it doesn't anymore,
i checked for power on the glow-plugs, they all receive power ( i used a probe light) for about 10 seconds, then the power is gone, could that mean the plugs are actually still working and only my light is broken or has a loose contact?

any suggestions are appreciated
thanks

300Dman

The Glow Plugs themselves are most often the problem. The Relay will still give Voltge to a bad Glow Plug. When you use a Test Light you create a separate circuit so the light lights up.

If you live in the US; Harbor Freight sells inexpensive Volt/Ohm Meters (Multimeters).
Go to the Diesel Giant site where he has a pictorial on how to check your Glow Plugs with the Meter.
http://www.dieselgiant.com/glowplugrepair.htm

Another issue is that Carbon build up around the Glow Plugs allows some of the heat to be transfered into the Cylinder head instead of heating up the Air in the Cylinder like it is supposed to.
If you remove any Glow Plugs you should Ream or use an alternative method to clean the Glow plug holes so that the new Glow Plugs will last longer.

My recommendation to go to the Diesel Giant site does not extend to buying stuff from him; as I think he is a little overpriced on most of what he sells.

nebojsa33

thanks for the links, doesn't sound so hard to do, and i have all the tools,

my car is converted to veggie fuel as well, so it will be a little harder to get to the plugs since there are a lot of things in the way, but i will give it a shot...

thanks
nebojsa

240D 3.0T

Good excuse to remove the junk and stop abusing your engine.

dega

mine, got 5 years long life