1972 220D - New Battery, new glow plugs, won't turn over

[kbee]

So after replacing the primer pump a couple weeks ago, my 220D started sounding like the battery was dying when I started it, and after a few hard starts it stopped starting at all. I had it towed to a shop, where they replaced the battery and then replaced the old loop type glow plugs with a new kit. I was surprised that the glow plugs needed replacing because the pre-glow coil had been getting red, and the plugs were definitely getting hot. But I never checked the voltage so I thought maybe the mechanic was right.

I picked the car up a couple days ago and it seemed fine, but there was a leak around the primer pump. I brought it back to the shop, they fixed the leak, it seemed fine all yesterday but then last night it was harder to start than it should be. And now this morning it won't turn over at all - it sounds like the battery is completely dead! I haven't done anything silly like leaving the lights on all night. Now I'm thinking the glow plugs were not the issue and I spent all that $ replacing them for nothing

Of course it's Saturday and all the MB shops are closed. Thought I'd see if anyone on here had ideas about what might be going on. It definitely sounds electrical to me, but I'm no expert. It was raining yesterday, maybe something is getting wet that shouldn't be?

[amt230]

Although no one responded to this, I am having a very similar situation, and wondering if this might be an issue with the rain.

I recently had a new starter put in and replaced all the glow plugs on my 220d. Now tonight when I went to start it, I got a glow, but when I pull the knob all the way out, there was just a clicking noise, but it wouldn't actually turn over.

Seems electrical? Any recommendations? I can't believe how much of a headache it has been trying to get this thing to start reliably. Ugh.

[79Mercy]

Is the battery fully charged?

If so check all the connection on the battery and check the ground cable which goes from the body to the bell housing. Also check both connections are the starter.

If all is fine, you have a bad starter. I honestly think its bad, but check those things i mentioned just be safe, on rare occasion it could be one of those things.

What kind of starter was installed?

[Shortsguy1]

So I am no expert, but it sounds like it has nothing to do with the glow plugs, and everything to do with the starter or battery. If your GP indicator on the dash glowed for you, then the GP circuit is connected and the other GPs were probably glowing as well. Regardless of whether they glow or not, the starter should turn over the engine. So if you poke around here on the forum, you will find directions on how to engage the starter directly by jumping or shorting the connections. I don't recall exactly how. But it will test if your starter is still working. And then check the voltage at the battery to see if it is okay. I am guessing that your battery is simply dead, which could be due to it being old or due to your alternator not charging it correctly.

Regarding the first poster, yes, I would guess he replaced his GPs for no reason. They have really no connection to an engine not being able to turn over (assuming they aren't running your battery down).

[newtodiesel]

Maybe when you go back ask if they have not thrown out your old glow plugs if you can have them back. Then if you want you can test them yourself to see if they are bad. Ask for all of your old parts back, most everything can be rebuilt.
Especially the alternator and starter (I think the starter can be rebuilt, but for sure the alt can be).

[ScooterABC]

Check the voltage of the battery when the car is off. Then check the voltage of the battery when the car is on. It should be about 2 volts higher. Is your generator/alternator charging the battery? That's what comes to my mind...

[amt230]

Thanks all. Haven't gotten the chance to yet, because of work, but I'm going to start by jumping it. When I returned to the car later to try to turn on, it wasn't even doing the clicking any more, and the dash lights seemed dim, so I think this is a battery issue.

I JUST had a new starter AND alternator (less recently, but in last two years) put in, so if it is either of those, it will be very frustrating. To be clear, I replaced the plugs separate from this issue, but was just noting it wasn't them.

There should be an addendum to the "these cars run forever" comment - "they'll run forever, if you can get them started."

Assuming it is a battery issue, I don't understand why its drained. I'll have to look into that, and potentially replace, I suppose.

[801mbz]

AZ will charge and test battery for free. To test for a drain on the battery take off the ground and put a volt meter on battery ground to ground wire if it reads high you have a drain to find. Un plug alt. pull fuses. I had a clock do it to me.

[amt230]

Thanks for all your help! So, it was a combination of issues relating to the battery. After trying to jump with a buddy's car, he just put the battery from his Benz diesel in and it started up. So, I bought a new battery (haven't gotten a new one since I bought the car 3 years ago, so it was likely overdue, if not the actual problem).

The next morning trying to start for the second time after a full night's rest, the battery was clearly having a little trouble. So, I figured it was draining. Based on 801mbz's advice, I tested voltage through the unhooked ground on the battery (I'm still learning how to utilize a multimeter, so this advice was helpful). Sure enough, it was reading 12 volts. I took out the clock (which I had recently repaired and reinstalled) and it dropped to about 0.4 - which I assume is healthy.

So, all my efforts to repair the clock, and now it's draining my battery when installed. Thanks for all your help finding this issue. But, I'm at a complete loss of how to fix it????

Anyone else ever have their clock draining their battery? 801mbz, how did you fix?

Thanks!

[katja]

Interesting...I've not heard of that little clock drawing enough of a load to kill a battery. My car usually sits for a week or two between uses and I haven't had any problems with battery drain, though this week it's on a trickle charger because it has been sitting for almost a month and the battery is over 5 years old.

My radio has a clock built in, and one of my future projects is to replace the dash clock with a VDO tachometer driven by one of those magnetic pickups that you stick to the alternator. It looks possible in theory but I haven't bought the parts yet.

[amt230]

I may have figured it out...

Because I've been working through rehabbing the clock myself, instead of pulling the dash each time to properly mount it to the instrument board using the nuts, I've just inserted in from the front and it holds in place and makes contact with the power source.

While reading up on how to bench test the clock, I realized that I couldn't find the ground on it. As it turns out, one of the two mounting bolts is actually the ground. I realized this when I was poking around on the instrument panel. One of the holes through which you put the mounting bolts of the clock is lined with metal that flares out on the back side of the board. That flared out piece connects to the circuit board, and when the mounting nut is in place it completes the ground.

This is still a theory in some respects, since I've lost those little hand nuts that hold the clock in place to try it out. Anyone have extras? I don't know whether the specific ones are necessary or if any old nut will work. Think this is too crazy to be the problem?

[amt230]

Well, in the meantime, my neutral safety switch became enough of an issue that I needed to replace it. But, I am still working through the potential battery drain. My impression is that it is definitely the clock, but the way this is working out is confusing.

When I put my multimeter in line with the disconnected negative terminal on the battery, I read about 12 volts with the door open or another light enabled. When I put the clock in and the clock running, it reads 0.4 volts (which my understanding is okay). But, if I insert the clock and it isn't wound (and doesn't get enough power across the multimeter's lines to rewind it), the multimeter reads 12 volts. If I just connect the battery quickly to wind the clock the multimeter drops back to 0.4 volts.

So, it appears that if my clock stops it will start draining the battery. This doesn't make any sense to me.

Also, is there another method (amps?) to measure battery drain? I can't seem to get that to work on my Klein tools multimeter. Any help appreciated. Thanks!

[Mike D]

That's how the clock works in the older Benz. It isn't like a "standard" electric motor which is under a load constantly. Power is only used to "wind" the clock, the mechanical portion takes over, the spring winds down, the clock "re-winds" and the process continues.

This is a very simplified explanation of the actual process. If you wire the clock remotely and sit it on a bench you can hear the "click" as it resets.

[TnBob]

Your fully charged battery should run your clock for 3 or 4 months at least.

The symptoms you describe sound much like my 82 - 300D Glow plug relay issue.
The light goes out but a bad GP relay will continue drawing on the system.

A quick check is to pop the cover and measure the voltage on the 4 pin connector that doesnt go to the actual glow plugs. IF you get ~12vdc at any pin while the car is at rest your GP relay is bad. JY's or at least my best local one charges $2.

[meltedpanda]

you have a short somewhere else, or a drain
Tnbobs ideas are good ones, you can also test across the fuses to see which ones are active with the key off and work back. Some should be most should not