Greetings!
I'm having trouble diagnosing a starting issue.With the cold weather and no garage and an intermittent issue running tests has been hard.

1983 240d automatic
starter may be original, can't tell?

The car starts normally most of the time. When it doesn't, I always hear the solenoid click, there doesn't seem to be a weather/temp/ usage pattern to when it fails.

It always starts if I short together the large (+) bolt on the solenoid to the small (+) lead on the solenoid. If I short the 2 large bolts it just sparks.

Sometimes it starts if I wiggle the gearshift, however, since I hear the solenoid clicking whenever it's in P or N and not the other gears i think the NSS is working OK. I think I'm just reengaging the solenoid when I do this. Backup lights are fine.

I tried bypassing the NSS by jumping the headlamp switch (+) terminal to the purple white pin under dash (to starter sol.) still just a click. I think that rules out the Ignition switch too? Wiggling the Ig Sw doesn't help.

Sometimes rolling the car a few feet then trying to start it again gets it to start. but that didn't help today.

Had battery / charging system / starter circuit test from Advance Auto (for what it's worth) all checked fine. Of course it was starting that day anyways. Battery is 8 months old.

I've cleaned (with battery terminal cleaner) and tightened chassis to engine ground strap. Batt (-) and chassis terminals and Batt (+) terminal.

With Voltmeter 12v from battery, 10v at solenoid (+) terminal when key in start position. This with analogue meter though so not sure of accuracy.

Having hard time tightening alternator belt (worn out tensioner)but it's not terrible.

So I would just put in a new starter and hope for the best but I'm concerned that since it always starts from the screwdriver trick as stated above.... that It might be something else

Any suggestions for a next step, anything I've missed or need to re-check?

Thanks!
Sean

Think its time for a new starter, go get a 300d turbo starter and put it on...

On my dart, I had this issue....when the starter was going...if I sorted it at the solenoid it would turn over....limped it along doing that for a bit...

__________________

In Michigan, I often find the throw shaft corroded.
How the starting system works | How a Car Works
Disassemble the starter.
Remove the Bendix, clean - lubricate the shaft and re-assemble.

You may also have a ground or switch issue.
Ignition Cylinder Tumbler replacement; mixed diesel/gas

.

__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

https://www.boldegoist.com/

Thanks!
The solenoid was "trying" but no cranking
when you had the issues?
And new starter fixed it?

Disconnect a Negative Cable at the Battery.
See the pic.
Remove the Cable from #2

Keep the Cable end you removed away from any Ground and reconnect the Cable at the Battery.

Touch the Cable from #2 to the Starter at #3 and see if the Starter rotates. If not check the Battery to Chassis Ground and the Engine to Chassis ground and try again.
If nothing happens or it sparks alot you have some issue inside of the Starter.

If it rotates OK try having someone turn the Ignition Key on and they you touch the Cable to #3. If it cranks normally like that the contacts inside of the Solenoid are burned.

Not it is a good idea to wear some Leather Gloves and Eye protection.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

12v at the battery at rest is too low. Should be 13v + ! The cheepie harbor freight meters give a good DC voltage read.

Obviously your alternator tension needs help. That is the 1st thing to do. Hate to see you replace a starter for a loose belt which = insufficient charged battery.

__________________
1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

On second thought It was 13v at the battery at rest..... a while ago with cheapy meter.
Already checked the Battery to Chassis Ground and the Engine to Chassis ground. Cleaned contacts and 0 ohms between them.
Will tighten alternator when I can get to it.
Was Diesel 911's suggestion the same as shorting #2 & #3 together? This produced sparks but no rotation.
Shorting #2 & #1 always gets it started for me.
If I understand it, and I may not. #2 to #3 puts battery (+) right on the starter.
And #2 & #1 puts battery (+) right on the solenoid.

Thanks for the responses

Shorting #1 and #2 is the same as using a Jumper Wire from the Batter to #1. If the Starter always works like that I would be thinking that you have some problem where the Circuit going from the Solenoid to the Ignition Switch is not getting Electricty to the Solenoid or there is some resistance restricting the current flow in that circuit.

I numberd the pic the same as the other pic there is no #1 because you cannot see that in the Pic.
When the Solenoid pulls back the Plate bridges #1 and #2 contacts connecting the Battery to the part of the Starter that rotates the Starter.

Over time it is not uncommon for the Contacts to burn.

Attached Thumbnails

 

__________________
84 300D, 82 Volvo 244Gl Diesel

I just took off air filter So I can see the starter.
It's warm and sunny Which helps!
The red wire coming in to #1 uses a
Crimp blade style connector which had play
In it and exposed to elements.
I tightened and cleaned this and it starts
Right up after multiple no starts.
This makes sense as every time I touched this
Connector with a screwdriver it starts right
Up.
But I guess since I was getting a click
From the solenoid it was the loose connection
Causing a resistance so solenoid not engaging
All the way?
I hope this is it, I'll be thrilled.
Gonna work on the alternator and see
How it goes.
Thanks !

A simple lose connection.

.

__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

https://www.boldegoist.com/