My 81 300SD does not want to start no matter what. We had a freeze last night, it's currently 44F, warm to some here on the list, but cold to us. But my diesel simply wont start up. It cranks and cranks and cranks up, but never turns over. And the temperature will hit 30F tonight, so it will get only worse. I know a diesel should start without effort in those temps, but mine won't. I have no block heater since we're in Houston. I want to know how to start a diesel in cold weather, and I think it could also be the battery, I don't know. Any help will be greatly appreciated.
-Joe

__________________
'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

Might try squirting a little plain old gasoline into the intake. My last 220D didn't like cold weather at all, and I had to do this on below freezing days. (Works like using starting fluid in a gas engine)
You may have water in your fuel that froze up in the fuel system somewhere too. May need some additive in your fuel tank for that.

__________________
past MB rides:
'68 220D
'68 220D(another one)
'67 230
'84 SD
Current rides:
'06 Lexus RX330
'93 Ford F-250
'96 Corvette
'99 Polaris 700 RMK sled
2011 Polaris Assault
'86 Yamaha TT350(good 'ol thumper)

How many miles are on your engine? Since you have the 617 engine, when was the last time you had the valves adjusted, this will play into the enigne's ability to crank over. 44F degs. should not prevent the engine from firing over. When I had my '80 SD, she didn't like it when the the temps got down to the low 30's. It has been said that an engine with low compression will be hard to start when the temps get low. Being that the engine in that car had almost 300,000 miles, I chalked it up to that. However I had a block heater at my disposal to help it out.
Also, what weight oil are you using?
Another trick you can do is when the glowplug light goes out, wait another 10 secs. or so, then crank it over. Have you checked the strength of your glowplugs? They shouldn't read anything more than .5 ohms. Anything higher, to infinity (an open) is not good.

__________________
1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member

I've determined it is the battery. After going through its history, I realised it experienced these problems before due to a low battery. The temperature decrease was so big in such a short time it could have affected the battery. So I'm going to get the battery recharged, and see if that really is the problem.
-Joe

__________________
'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

Also, when I tried to start it up earlier today, after I took the key out, I noticed a humming noise coming from the circled object. What is it? Vaccum pump? Fuel pump? It's a shame, I don't even know what it is, but I know you can help me out here.
-Joe

Attached Thumbnails

 

__________________
'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

The vacuum pump for the door locks is located in there.

__________________
2001 Dodge Ram 2500 Cummins Turbo Diesel - 4x4, auto, 3.54 gears, long bed
-------------------------------------
'92 300D 2.5 Turbodiesel - sold
'83 300D Turbodiesel - 4 speed manual/2.88 diff - sold
'87 300D Turbodiesel - sold
'82 300D Turbodiesel - sold

Mine would not start a few months ago. Thru this forum
I found that the glow plug relay fuse was bad. Its on the
driver's side towards the front and about the size of a ciggarette
box, and the lid comes off and there is a strip fuse inside.
Fixed me right up.

Sorry to here that it is cold in houston

It is colder here in chicago.

Check the fuse. Check the glow plugs with on ohm meter.

But before all of that allow the glow plugs to warm up.

Turn the key and wait a good 15 seconds and then start the car. The glow plugs stay on after the light goes out in the dash.

THat will make a big difference in how she starts up.

good luck

bob c

Well technically you did not freeze last night, It got down to 35 last night at the airport. Out lying areas who knows. But 35 is cold for a Houston car.
Your problem will be the condition of your glowplugs. I would suggest taking them out. Testing them and reaming the glow plug holes. Replace any that are bad. When you can, adust your valves.
Untill you can do that try to put a lightbulb in the engine compartment over night. A 100 or 120 watt bulb on top of the engine. Better yet under the car touching the oil pan to warm the oil. Of course not touching anything that could melt. will help a little in the morning. You need to add heat to the block so that the diesel can ignite in the morning. A ceramic heater will also help.
A block heater would be the best for you, Do you have one installed? Open the hood and look near the front of the radiator on the passenger side of the car. Do you have a plug that looks like a 3 pronged lamp plug, then you have a block heater, plug int in.
If not fixing the glowplugs is you best bet.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

H-Boy,

See if the overhead cabin light dims slightly when you turn the key switch to the start position. If it doesn't dim, the problem is in the GP relay or wiring in the GP circuit.

If the light dims, wait longer before you crank the engine with the starter. The GP stay on about 40 seconds even though the dash light goes out but are turned off as soon as the starter is energized. So its better to do short crank cycles, reheating the GP between each cycle than one long crank.

P E H

Ok, I've just read your posts, and this is what I did before I read them. Just for a test, I turned the lights on, and tried to start, and the lights went out completly until I released the key from the ignition position back into the "glow" position. I'm thinking it could be the battery, since it drains the lights to just to try to start up. I just saw your post to wait 40 seconds after the GP light goes off to start. I waited about a minute earlier today with no start. So I think it is the battery. I'm thinking it is someway connected to my inoperable tail light. It has a possible short in it, and that could have somehow drained the battery. I had a problem that drained my battery a few months ago when the rear domelight would not go off. It was an electrical problem. I'll have to see in the morning.
-Joe

__________________
'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

Check the water level in the battery and trickle charge it overnight.

If it hums for more than a few seconds when you lock or unlock the doors, then that explains the weak battery.

__________________
Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References

H-Boy,

Waiting a minute is too long. By that time thg GP have been off for about 20 seconds and are no lnger glowing red hot.

P E H

There is something wrong with that vacuum pump. About 11 years ago when I was about 5 or 6, the door locks stopped working automatically, and for some reason, my dad didnt get it fixed. It needs a new vacuum pump I think, and it cost an arm and a leg to fix back in 92. I don't know how much it costs now. It might be cheaper, or more expensive. So all the doors are locked and unlocked manually and the trunk is opened by key. The pump only made noise when I stopped trying to crank to engine, and went off about 10 seconds later, but it never came on when locking and unlocking the doors. I don't remember hearing it when turning the engine off when the battery was working though.
-Joe

__________________
'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.