As the title says. I just picked up this 1983 240d. It was in a flood (maybe up to the bottom/top of the seat, not sure honestly) about 3 years ago. Other than that I believe it has been sitting for the past 14 years, and was running perfectly when parked. 176k miles. Extensive service records. I believe it was well taken care of, but who knows I may be wrong. Here is what I've done in an attempt to start it.

-Flush engine/new oil+filter (no water)
-New fuel filters
-Running fuel supply into a separate tank w/ clean new diesel and some injector cleaner
-New coolant
-New battery
-Cleaned air filter housing
-Trans fluid is clean
-Checked fuses




Here's what happened. Upon first turning the key, the glow plug light was working. When it went off, I turned the key and the engine was turning over smoothly. Cycled the key a little to just let the plugs warm up. Tried again, car sounded like it fired once or twice, then nothing. Soon after, the glow plug light went out, and I noticed the glow plug relay was so hot it couldn't be touched. Now I can't get the light to come on. Fuse didn't blow. I removed / disassembled the relay, and found it was rusty and had moisture in it. Tested, im getting power at the relay, but the plugs get no power anymore. Maybe it's bad?

I pulled all 4 glow plugs, when tested, they get red hot on the tip within 6-8 seconds. Cleaned them, installed, and hooked up leads to the end of each, running them to the battery in order to bypass the relay for now.

They are getting hot, but the engine still won't even fire.

It's like 20 or so degrees Fahrenheit here.

Should I spray WD-40 in the intake?

Thanks in advance. Trying to decide if I want the car as a parts car for my w123 300d, or keep and drive it. It's light ivory/palomino, very clean interior. Wish it was a 300d :/

When I change my fuel filters, I have to turn over my starter for more than a minute and do it in 20 second intervals with a few minutes between each interval so the starter doesn't overheat. (I have a '98 e300). That is to get enough fuel into the system. I suspect you have to do the same.

Are you using a block heater? You may need one to start an '83 diesel in 20 degree temperatures that hasn't been started in 15 years. At 20 degrees you are getting into a temperature area where some people routinely use block heaters on older diesels.

If you are not using a block heater, I suspect you would be best off to wait until the temperature has been above 50 degrees before you try to start the car again. Wait until the second day so the temperature of the motor rises.

There are lots of people who know more about '83 240s than I do. Give some of them time to weigh in before you do much more.

If the engine has an acrid white-ish vapour out the exhaust when cranking, that will be raw diesel vapour, so would rule out the fuel system being gummed up at least. In that case you need heat to get it going as mentioned above

__________________
1978 300D, 373,000km 617.912, 711.113 5 speed, 7.5mm superpump, HX30W turbo...many, many years in the making....
1977 280> 300D - 500,000km+ (to be sold...)
1984 240TD>300TD 121,000 miles, *gone*
1977 250 parts car
1988 Toyota Corona 2.0D *gone*
1975 FJ45>HJ45
1981 200>240D (to be sold...)
1999 Hyundai Lantra 1.6 *gone*
1980s Lansing Bagnall FOER 5.2 Forklift (the Mk2 engine hoist)
2001 Holden Rodeo 4JB1T 2WD

I didn't hear anything of you trying to bleed it to get the air out. Crack one injector line at a time and purge the air and then go from there. Don't crank it too long. 30 seconds and 3 minute break each time.

Never spray anything in the intake while the glow box is working. If you ever get desperate to fire an engine up then at least remove the 80 amp fuse from the glow box.

You should take the advice from Jake12tech and make sure the fuel lines are purged of air. Don't create more problems by burning the starter motor. Open the fuel lines at the injectors just enough to relieve the pressure while you have someone turn the engine over a couple times.

When fuel squirts out around the nuts on a line move to the next. If the engine doesn't fire after bleeding the secondary filter and lines then start looking for places where air might be sucked into the fuel lines.

Let us know how this goes.

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84 300SD
85 380SE
83 528e
95 318ic

Sounds like the glow plug relay died on you. The heat was from the points having a bad connection internally. Time for a new relay.

In the meantime, remove the fuse from the GP relay just to be safe and try using WD-40 to start it, OR just wait until you get a replacement GP relay... At 20˚ I wouldn't expect it to be very easy to start without some preheating.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

Will try cracking the lines later, didn't think of that.

So no WD40 with the glow plugs red hot? Will it destroy them? I've fully disconnected the relay, so i could take it inside and disassemble.

I just have wires ran from the glow plug to the battery now, and just touched the wire to the battery when needed.

Absolutely amazing. A modern car would be toast in this situation due to the electronics down in the floor board level.

Remember you need fuel, air, and compression for the engine to run. The diesel cycle relies on the heat of compression to bring the air in the cylinder above the auto ignition temperature of finely atomized diesel fuel. When the engine is cold it needs a little help with building warmth on startup, so that’s why you need the glow plugs.

The reason for cracking the nuts on the injectors to release the trapped air is you are trying to open a spring loaded valve in the injector. If the pressure pulse from the injection pump hits an air pocket in the line it will just bounce off the air pocket and won’t be able to push the valve open in the injector to inject fuel into the cylinder.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

I believe someone on the market has a bypass setup built for the relay of the 79 and earlier mb diesels gp systems .If one gp was out in this earlier setup all the others behind it would not get the current ( SERIES WIRED), the reason for the old looped gps.The pencil style plug system (PARELLEL WIRED)which you have ,just a bad relay in your case, could benefit from this kit WITHOUT THE GPS ,a mounted push button which you can have setup anywhere in the dash area gives you any amount of time you think is needed to glow .Something like $100.Im currently helping an individual with a long time sitter.A 79 300cd.Alot of fuel issues in this case,one suggestion in priming is to wipe all the lines dry at their hoseclamp areas first before starting for a prime. This allows a look for any leaks.Once this has been establish you want to crack all hard lines at the injection pump, once you get fuel here retighten all lines then crack at the injectors and repeat process.Once you have fuel at the injectors by turning the motor over prime your thumb pump up 30 to 50 times ,if you see fuel moving you can tighten up the injector line connection .Its now ready to test fire with some glow plug due dilagence you have already performed .Good look ,I like to see some of these victory stories ,so many get sent down to a yard with no care.

Note OP has an 83 240 D which is the parallel wired system. His relay got shorted out by the flood waters. If he replaces the relay he ought to be just fine.

Good point about the primer pump. Note that the original, white knob, primer pump unscrews to unlock the plunger to pump it up. This pump is notorious for leaking and you may have to replace it, since you will end up just pumping more air into the system if it’s leaking. There is a Bosch replacement for that pump, that is just a big black rubber cylinder that screws into the same hole. This one you just press down on the rubber cylinder to pump the primer. In either case there is a distinct difference in sound once the injection pump is primed. What it is actually doing is forcing extra fuel through the pump and pushing the air and excess fuel down the return line on the back side of the injection pump back to the fuel tank.

Note that this is separate and distinct from the need to purge the injection lines as I mentioned previously.

For education of the OP, the older engines had series wired glow plugs, and instead of an automatic relay that was triggered by turning the key to II position, you pulled out a large heavy knob (known as the “gorilla knob”) and instead of a standard pilot light, there was an extra element in a cage in the dashboard (known as the “salt shaker”) that glowed red.

The newer system (like in your car) has a big relay that is controlled by turning the key to position II. When the light goes off, the timer has determined that you have glowed long enough (based on an ambient temperature sensor in the relay, later models have a temperature sensor in the head). This is your cue to attempt a start.

Note also the 1983 240D has an EGR valve controller box behind the kick plate in the passenger footwell. I would check this out and make sure it’s not shorted out either.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

I agree with jay bob and the other fellow who said your relay is probably fried. If you're getting fuel and compression you should also be able to pull start it.

I don't see any problem with spraying wd 40 in with the glow plugs acting. Its just like diesel fuel.

But to me it sounds like the relay.

I had a car which flooded up to the intake and most of the stuff worked afterword. It was a gasser though so no glow relay.

Don't forget to change your diff lube. Its vented so can fill with water.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Thanks again guys. Going to crack the lines and see if i can get fuel. I will say, when i turn the engine over, or pump the primer pump, i can see fuel being pulled in, along with fuel returning back into my makeshift tank. Even though fuel is making it all the way through the system, could i still have air in the system?

So today i manually hooked up the glow plugs to the battery. All four of them were hot (let it sit for about a minute) Turned the key- nothing. Still just turning over. Not the slightest sign of firing. I even sprayed WD 40 in the intake- still absolutely nothing. Not even trying to fire. and it has warmed up to like 50+ degrees.

Im stumped. I can watch fuel coming back out of the return line into my bottle, i dont see any serious leaks (other than one leaky fuel return line, only noticed when pumping the primer). Primer pump actually looks better than my 300d primer pump.

Did you bleed the system after replacing the fuel filters? Does it have the original white bleeder pump or has it been replaced with the black plunger? If it is the original white one, it could be sucking air into the system. If you have not already adjusted the valves, you will need to do that . If they are tight, that will keep it from starting. It sounds like your GP relay needs to be replaced for sure. If it it cold, and you did get the glow plugs working manually, you will need to crank it until it either starts, or the battery runs dead. The starters on these are built and designed for long cranking times and it will not hurt it. If all else fails, I have had diesels that have sat for many many years that I ended up having to pull start the first time to wake it up then it started on its own after that.

Yes, do that before driving. Pull starting is the way to go, starters are slow (and expensive).

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1985 300TD 1981 Scirocco 1.6D conv 1986 Golf 1.6D 2003 Golf TDI

Uh, no. The immediate danger is that if ether/wd40/starting fluid encounters a hot glow plug it can ignite instantly. Depending on the location of the piston at that moment, it may try to rotate backwards halfway through a combustion cycle, resulting in a bent rod or even a broken crank. Use a little too much, and it can cause an explosion in the intake with personal injury as a potential outcome - essentially turning your intake manifold into a pipe bomb.

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1998 E300 turbodiesel

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