Cold starting problems today (it was about 10deg) and so I wore the battery down. I was jumping it off the truck and in the middle of cranking it just stopped. Now it wont crank at all, no click, no nada. And yes the jumper cables were hooked up right. Any thoughts on what I broke. I have to drive across the state tommorrow and I'd really rather take the benz than the truck.

79 300SD

First, get a heavy duty charger on the battery as soon as possible.

Also, try to turn on your interior lights before you crank, then when you start to crank you should see them dim, if you dont, then something is wrong with the ignition.

When you jumped it with your truck (what kind of truck??) did the starter speed up at all? How long did you let it sit before trying to start?

If the truck is a gas truck, and you didnt let it sit for a good 15-20 minutes before you tryed to start, the jump probably didnt help too much...

The truck is an old landcruiser, I hooked it up and let it idle for about 10 minutes before trying to start it, it didn't seem like it was helping before it stopped cranking. The interior lights come on but when I turn the key nothing happens.

Could I have fried something in the ignition by jumping it?

If not mistaken a landcruiser has a 24V electric
system.
But I could be mistaken.

Hopefully not, you might have fried the starter and/or
battery.

Louis.

it's not that old, an 89 FJ62, with 12v

You may have welded the starter or solenoid contacts together by cranking it with low voltage. I'm not a Toyota expert though.

It's possible you cooked the battery. Remove it, try to charge it (preferrably indoors) reinstall it and then see what happens. If you have a friend with another battery try that instead. I recently went through this with my 124 and found a cell had collapsed in the battery. By the way, check the output of the alternator when you get it running. My battery died because the brushes on the voltage regulator were worn out and the red idiot light on the dash never went on. The circuit works, the red light lights when I turn the key, it just never went on when the Vreg stopped working. A hint that the battery has a bad cell is that the voltage won't stay up or the radio won't work (they are very sensitive to a voltage drop).

__________________
LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

Jumping these engines is always a dicey proposition.

The reason is as follows:

The jumper cables clamp onto the terminals and contact the terminals at two or four points. The amount of contact area is very small.

Now, you are trying to get something like 500 amps to flow through these small contact points in order to turn the starter fast enough to start the diesel.

This normally is not successful.

I have found that I must jump the vehicle and let it charge up for 20 minutes, as you have done, with the donor vehicle at fast idle if I am going to have any hope of getting it to start.

Even with this practice, I only have about 10 seconds of cranking power before the starter speed drops off to nothing.

If you have a diesel that needs 30 seconds of cranking in very cold temperatures, you absolutely need a fully charged battery and the battery must be in very good condition.

I would encourage you to remove the battery from the M/B and charge it up indoors. You will then have a warm battery to put in the vehicle. If it will not provide at least 30 seconds of crank time at a good crank speed, replace the battery immediately.

Is the starter still not working? Possible thermal overload sensor tripped in the field windings? Just a guess...I've never had one of these apart

Its rare that a starter just stops dead...it will usually die out or atleast give you a little smoke when it bites the dust...(or smell burnt)
I'd check out your battery and cables and perhaps look at your solenoid.

Brandon

koop,

I think you have an open circuit in the battery/starter/ solonoid circuit. I doesn't take much resistance in a high current circuit to make an open circuit.

Tighten or better yet remove, clean and retighten all the terminals on the high current cables and the terminals on the solonoid and starter. Also clean the battery terminals and posts.

If you have a voltmeter, connect it across connection points when you energise the starter. The place that reads almost 12 volts is the bad connection. You can also do this across the battery post and connector.

P E H

#1. Low or bad battery.
#2. Starter is toast.

How long did you crank it, and how long between cranks???

Fifteen second maximum crank time, or you toast the starter...

Do try terminal cleaning, if you are very lucky, it might work.

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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
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Sorry to hear that,
Here is a thread I started some time back you might find useful, many opinions....
http://www.peachparts.com/shopforum/showthread.php?t=109607&highlight=battery+cranking+kill
I cranked until battery was dead twice, and had two dead starters to show for it.
Never again.
If you do get a new one, make sure to get a good warranty; these diesels seem to eat them for lunch.
I got a lifetime warranty on mine this time.
Now its just a matter of an hour under the car fighting it...

__________________
Think Alternative Energy!
300CD '80 (now gone but not forgotten...)

Yeah Ive got the lifetime warranty starter and it has come in handy on several occasions.

I agree that the problem is either the battery is graveyard dead or the starter bit the dust. Charge the battery up clean connections. posts etc and If it still wont turn over move on down to the starter(which is not a fun job )and I bet it is even more enjoyable in winter.

__________________
'85 300 Turbo Diesel- 308K

The first thing that you should do, and that no one has mentioned, is to go to Wally-World and but a $0.99 battery hydrometer. Hell, buy 5 of them. Charge your battery overnight and then test each cell. If one is low, esp. during the winter, scrap the battery. If one cell is bad the rest are not far behind and you can guarentee that the battery will leave you stranded this winter.

When the battery is out of the car, clean the battery connections, esp. the inside, clean the solenoid connections, and the engine ground connection. When you reinstall the battery connect a jumper cable to the battery cable at the solenoid and scratch it to ground. You should get a very healthy and loud spark. If not, your battery cable is NFG.

When, as, and if, you buy a new battery don't get one of 1,000+ amp jobbies. Get the one that the manual calls for. About 550-600 amps is good. The mega amp ones won't last in the heat of the summer and you are just throwing good money down the drain.

With a hot battery and power to the starter jump the solenoid and see if it will crank. If it doesn't crank your solenoid is bad. If it cranks then the problem is between the switch and the solenoid. There maybe a fuse in this circuit, I am not sure.

If you cranked for a long time I would guess that you have fried the solenoid's guts. The starting circuit doesn't really draw enough current to fry anything, but the solenoid certainly does.

Good luck

koop,

What Kip says about getting a smaller battery is ridiculous. Get the highest ampere hour and CCA battery you can. If it dies in the hot weather, that is what the warranty is for. But the batteries I've seen, almost always die in cold weather when the most power out is needed and the battery is at its weakest operating temperature.

I suggest purchasing a battery from AutoZone. Their group 49 for MB is 1000CA and has a 7 or 8 year nationwide warranty and costs about $65. The battery is made by Johnson Controls, known for making the best batteries.

Its possible you have a dead spot on the starter armature. The current to energize the pick coil of the solonoid has to pass thru the starter armature. Thus the solonoid may look bad when it is really a bad starter.

Here's a test: Make a connection from the output terminal of the solonoid to ground. You can do this with a wrench or heavy screwdriver. If the solonoid jumps in, the starter is bad. Don't keep the connection on after the solonoid jumps in, as it is now a direct short to ground. And don't jump to high if you get some sparks. Its only 12 volts so you won't get shocked. Don't touch end of shorting tool, it may be hot. This may cause the starter to operate because the jump of the solonoid may move the armature enough to move to a live spot on the commutator. But eventually you will be on the dead spot again and starter will not work.


I used to have an old Ford starter that would not run when it stopped at a certain point. That starter had a metal band covering the brushes so removing this and using a screwdriver I could turn the starter slightly and get it to work.

P E H