I seem to be having glow plug troubles. I have been having trouble with starting the car for two days now...It is very cold so I have been thinking it was a low battery issue...but now I think the source of the problem is the glow plug system.

I have been charging batteries for two days now as well as I brought one battery in overnight to thaw out and recharge. According to the guage on the battery charger the batteries are taking a charge.

I just finished installing the thawed out and fully recharged battery but did not get the car started... Since last using the car my glow plug light stays on for a long time compared to normal. I get the car turning over...but not as fast as it should with a fully recharged battery and only after one glow cycle.
On this final try I took off my mit and bravely touched the end of the front two glow plugs on the nut that attaches the wiring to the glow plug....and not a bit of heat could be felt.

Is there something that could be creating a major short and not allowing this fully recharged battery to turn the engine over fast enough to start?

I was under the impression that the glow light on the dash would not come on if there was a glow plug problem? I have that glow light on the dash coming on albeit for a longer period than I am used to?

I kinda thought that the glow plugs would stay on for longer if it was cold out...but if they are on a timer than maybe that is the problem....where is the timer?

I feel silly thinking that somehow the glow plugs know the temperature of the engine block if it is cold out....I guess it would need some sort of temperature sensor feedback system. Glad to know of this timer. Thanks.

The later W123 models use ambient air temp to control how long the light remains illuminated and how long the glow cycle lasts.

On the five cylinder engines, it is possible to have one bad glow plug (as long as it's not cylinder #1) go undetected by the fault detection sytem.

1980 300TD
1985 300TD
1979 300D
Which one is having the no start issue?
Does the 1979 have Loop/Filiment type Glow Plugs; if so the troubles hooting process different.

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84 300D, 82 Volvo 244Gl Diesel

Sorry, should have included the car with the problems.... it is the usually faithful 85 300TD.
So the fault detection system you describe....would that be the glow light on the dash? I wonder if that explains the unusual amount of time for the glow light staying on? So a glow plug other than the number 1 (front of engine) could be faulty leaving me with the dash light still coming on?

So for example: If the #2 glow plug was faulty would that render 3,4, & 5 not working...but because the #1 glow plug is still good then my glow light on the dash is working giving me the false impression of good glow plugs. That would explain why the car won't fire. It is only using 1 glow plug to start in -43c.

I was just talking with a buddy over ther phone and he thinks my putting a finger on the wire side of the plug to be most unreliable as the temperature outside is too cold to be useful. He thinks that I won't feel heat on the outside of the block since the metal from the block will absorb the heat before it gets to the outside of the engine. It is -43C outside right now so I am tending to agree with him.

It is really cold and dark right now. I froze my left ear three times today....I am thawing out my body to go and take the battery out for the night. I would sure like to test the glow plugs before I take the battery out for the fourth time. I would also like to check this relay/timer thing. I have taken the bolts off it and found it to be on the inside front ds fenderwell just behind the headlight ......took the bolts off to have a good look at the fuse...it seems fine. I have to work outside and fingers freeze quickly. there must be a quick way to test these plugs and relay.

On a 1985 model, the glow plugs are wired in parallel. One plug failing has no affect on any other plug.

If the fault detection system is working properly, the light remaining illuminated guarantees at least four operating plugs.

Agreed.

Can you quantify "a long time?"

A common failure mode for the GP controller is short cycling. You might want to measure the amount of time the relay remains closed. With the engine off, you can easily hear it "clunk" when it opens.

Pull of the harness for the glow plugs at the relay and do a resistance test through the harness using an ohmeter. Report back.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I assume the temperature is between zero and negative 40°.

There is a glow circuit coolant temperature sensor = colder glows longer.

IGNORE the glow light !!!

Try double glowing:
#1. Glow until you hear the relay CLUNK.
#2. Glow again until the relay CLUNKS.
#3. Turn off key, quickly turn the key back on and crank the engine.

For fastest engine COLD cranking speed use synthetic 0W-40 or 5W-40 engine oil...


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__________________
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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
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Hello, Thanks for moving this to a new thread....I was working on the car last night while posting and it was starting to get long winded with my problems....I was feeling bad for the o/p and was wishing that I would have started my own thread so thanks again vstech for moving this.

In post number four I stated the temp was -43c and this morning it is not much warmer. I am starting to get desperate to have this car running as it is my only transportation right now.

I will be going out to test the resistance of the glow plugs... soon as I am done typing

Just wondering exactly why to ignore the glow plug light? Is it not a reliable display of glow plug function?

I had problems last winter with number 1 & 2 glow plugs and it was easy to determine something was not functioning with the glow plugs as the light on the dash did not come on with the key turned to the glow function detent. I took two plugs from a spare motor and everything has been fine since.... glow light came back on.

I am wondering if maybe the other 3 plugs have gone bad. It started fine up until it got really cold, like three days ago.

I am also wondering if because the glow light is staying on for so long... is that indicating a bad relay/timer and could that be causing a massive drain on my fully charged batteries?...leaving the glow light on and functioning as if normal.

After glowing once with a fresh and warm battery I was experiencing the speed of the motor cranking over to be very slow, almost as if the battery was near dead. I tried the other freshly recharged battery and the same thing happened. I am thinking I have a massive electrical short.

Is there anyway that the glow plugs themselves would be responsible for a short like this that I described or would the relay be dumping all my battery charge? I took all the fuses out to rule out an accesory drain.

I have 5w 40 synthetic oil in the motor.

The reason it won't start is because the motor is not turning over fast enough. I know that...It could also be that it is because the glow plugs are'nt working either.... so I have no heat in the cylinders.

My battery is going dead almost as soon as I hook it up and try starting it with one glow function....I barely have enough juice to repeat it a second time and that is with two good batteries. One is less than a year old (interstate mega tron mtp-93 and the other is 5 years old (A/C Delco ACD49-60). According to the guage on the charger they have been fully charged. I am pretty sure that the batteries are good...I can't see having 2 bad batteries at the same time behaving the same way.


I feel it is something in the glow plug circuit dumping the charge from the batteries to the point they have barely enough juice left to turn the engine over fast enough.

Is that possible? I do have a spare glow plug relay/timer somewhere. I could also steal glow plugs from the 1980 300TD as it still has 15w-40 oil in it and is going nowhere anyways with that stuff in it in this weather.

going back in the deep freeze and will post results of ohm test of glow plugs.

... -43C!!! wow.
I don't think ANY diesel fuel will flow that cold even with serious antigel mixed in... most are only good down to -40F/C ...
in those temps, you'd need a fuel tank heater, block heater, and insulated fuel lines to run...

as far as the batteries, I'm sure they are toast.
a charger can only tell you how much the batteries are drawing. then cannot measure the capacity or cel condition...
you also could have a bad starter, but if it's cranking over, it's likely ok.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

also, the glow light on these cars is only an indicator of possible glow conditions... it is not reliable at telling if the glows are on or working, and it will go out LONG before the glow plugs do even when everything is working perfectly.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

with those temps, I'd get battery heaters, and pull the carpet and the tank partition and install a magnetic heater directly on the fuel tank. possibly TWO heaters! and close the trunk!

but you've got a wagon I guess from reading your sig line... the tank is UNDER the car on those... so no protection from the elements at all...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Can you post a video with sound of your starter? I can tell by the sound if your starter is spinning fast enough or not, that could nail it down to the starter or battery. Synthetic oil I assume?

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I assume you don't have a working block heater?

Get three of these.

Attach two on the oil pan, and the third to the passenger side cylinder block with power, for two hours.

Then try to start it.

magnet block heaters.
https://www.google.com/search?q=magnet+block+heater&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-USfficial&client=firefox-a

What you need is a glue on oil pan heater pad.
https://www.google.com/search?q=oil+pan+heater+pad&oe=utf-8&rls=org.mozilla:en-USfficial&client=firefox-a&um=1&ie=UTF-8&hl=en&tbm=isch&source=og&sa=N&tab=wi&ei=ln8YT8zbL8HLgQfusaiiCw&biw=1280&bih=803&sei=7H8YT7D7Jen40gHO49W7Cw

.

I agree with John. At -43 you need a block heater, huge dose of antigel and magnetic heaters on the fuel tank--which is easy to do on the TD. I'd also consider magnetic heaters on the engine oil pan. If not, I'd just let it run all night to avoid starting headaches. You could spring for a Webasto.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

At -43° you need two gallons of kerosene per tank of fuel, to prevent jelling - improve starting.


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