82 300D is hard to start when cold.

[Dave Billings]

My 82 300D is hard to start. The glow plug light never comes on but I do get twelve volts at the plugs until the reley shuts it off. Any ideas??

[athensbenz]

Do you know when or if the glow plugs have been changed? They don't last forever, but tend to work ok when warm but not when it's too cold.

[Dave Billings]

I don't know when they were changed, we just bought the car but that was what I was going to do next. But will the glow plug light not come on if the plugs are bad?

[tangofox007]

You need to check the resistance of each plug. 12 volts won't do any good if a plug is burned out.

The glow plug light's failure to illuminate is an indication of one or more failed glow plugs.

[kerry]

Under some circumstances, lack of a glow plug light indicates bad plugs. You need to test the resistance of each plug with an ohmeter. Digital multimeter works best. Each plug needs to be less than 1 ohm. More than that and the plug is bad. Plugs can sometimes be bad if old and ohm out adequately. Sure fire test is to remove the plug and hook them up to a battery with jumper cables and see if they glow bright and hot quickly. It's useful to have a good new plug to compare the response of the old ones.

[leathermang]

First try timing the glow plug " on" time... use 45 seconds the next time it is cold and see if that makes a difference...
This is straight out of the FSM...
Don't recycle... just leave it on that long..then hit the starter...

[Knightrider966]

Originally Posted by Dave Billings

My 82 300D is hard to start. The glow plug light never comes on but I do get twelve volts at the plugs until the reley shuts it off. Any ideas??

Take your old glow plugs out and test them by connecting them directly to the battery to see if they get red. Seeing 12 volts at the glow plug connections is not always accurate and your glow plug light will not light up if 2 or more have gone bad.

[dkveuro]

I find easiest way to check the GP system is to remove the injector hard lines and then the injectors...you need to take off the throttle bracket too.

Turn on the key and watch for all glows to turn bright red.

The rest will be obvious.

[running-snail]

dkveuro -

WOW - I'm over the hill too, but find nothing "easy" about your solution. Ohmmeter doesn't require removing the glow plug, or the injection lines and injectors - they can be tested in place.

I suppose if you don't have an ohmmeter, then I would be inclined to pull the plugs and test as Knightrider is suggesting.

Pulling the injector has to be pretty far down on the list of alternatives. You would recommend replacing with new heat shield when you pull the injectors, correct? For the cost of new heat shields I'm guessing you can pick up a cheap vom at harbor freight.

[vstech]

Originally Posted by dkveuro

I find easiest way to check the GP system is to remove the injector hard lines and then the injectors...you need to take off the throttle bracket too.

Turn on the key and watch for all glows to turn bright red.

The rest will be obvious.

.....
EASIEST? are you kidding? while this will indeed work, it will require you to carefully snap loose the injectors, because if you pull them with steady pressure, you stand a good chance of releasing your PC rings... NOT a good thing. Also, this will require new heat shields, and it will open up a MAW session. (might as well... ) so you get out the injectors, MAW have them pop tested to verify good spary and so on, you get the dirty heat shields out, and clean out the pc seats, fire up the gp's and look for the bad ones. simply change the bad ones out, oh, MAW change the good ones too, never know when they will fail. put the injectors back in and torque them to proper specs... MAW check the IP timing while it's open, heck, MAW pull the Valve cover off and check the valve clearances... new VC gasket... pretty soon the weekend is gone... does your car start now?

[tangofox007]

Originally Posted by dkveuro

I find easiest way to check the GP system is to remove the injector hard lines and then the injectors...you need to take off the throttle bracket too.

It's a lot easier to buy a ratcheting combination wrench.

[Dave Billings]

Thanks for all the help guys. I took all the glow plugs out except the one closest to the fire wall (can't figure out how to get to it) and hooked them directly to 12 volts and grounded them. None of them glowed. I Installed new glow plugs. Now the glow plug indicater lights up, stays lit for about 2 seconds, I turn the key and it starts right up. I'm a happy camper. Any ideas on how to get that one closest to the fire wall. I used a swival and a ratchet on the rest which worked great. But that one has the oil filter right in front of it.

[tangofox007]

Originally Posted by Dave Billings

Any ideas on how to get that one closest to the fire wall.

See post #11.

[toomany MBZ]

To get to the rear most GP, I loosened up some linkage, and moved that heater hose out of the way.
Worked for me, others may mention to remove the metal fuel line "rack" to gain access. I used ratcheting box ends also. Stick a rag down before you start, to catch the nut that may fall.

[dkveuro]

Originally Posted by running-snail

dkveuro -

WOW - I'm over the hill too, but find nothing "easy" about your solution. Ohmmeter doesn't require removing the glow plug, or the injection lines and injectors - they can be tested in place.....................................
Pulling the injector has to be pretty far down on the list of alternatives. , .................................................................. For the cost of new heat shields I'm guessing you can pick up a cheap vom at harbor freight.

Takes me 15 minutes to do this job including replacing the shields.

It has the benefit of allowing you to check the glows and system glow duration.

It's a snap to do a compression test then too.

I keep dozens of shields in stock.

I'm betting you can't even do #4 or #5 GP out in that time .

.