Starter Install Troubles

[903hblue]

Hey guys, lots of problems lately. After new injection pump install I killed the starter cranking away.
New starter, initially had a problem getting it all the way into the bell housing. Tried to start, starter turned but made a weird noise, like not making full contact. After wrestling it for a while finally got it installed flush.
I hook up the battery and now I can't get anything from the starter. I turn the key to the start position and there is nothing. Very frustrating after all that work.
I'm totally stumped

[Junkman]

Key to start sends current to the small wire on the solenoid and should measure full battery voltage. Measurement will be slightly less because of voltage drop caused mostly by old, dirty connections.

The positive cable should read full battery voltage at both ends.
Your neutral safety switch could also be causing a no-crank. Try starting with the trans in neutral instead of park &/or moving the shifter around.

You can bypass all switches by connecting the correct terminals that are mounted on the passenger side of the engine compartment of a 126. I can't comment on a 123.

[903hblue]

Thanks. I tried the shifter in various positions with no effect.

[903hblue]

I've checked OVP fuses, fuse #5, and obviously the connections on the start solenoid. I've been reading about "jumping" some pins on the k38 relay?
Any one have any other ideas?

[dieselbenz1]

Von Strudel I presume? Can you clip on a remote switch between the 2 starter terminals and test the starter?

[tyl604]

Jump the starter. If it is like the 126, you can do it with two screwdrivers using the wiring on the passenger side fender well. Forget which two screws you touch with the screwdrivers but it is really easy.

If that works, you may have a bad starter solenoid.

[903hblue]

Originally Posted by dieselbenz1

Von Strudel I presume? Can you clip on a remote switch between the 2 starter terminals and test the starter?

Yes, this is on the 1993 300d. You mean a volt meter?

[903hblue]

Originally Posted by tyl604

Jump the starter. If it is like the 126, you can do it with two screwdrivers using the wiring on the passenger side fender well. Forget which two screws you touch with the screwdrivers but it is really easy.

If that works, you may have a bad starter solenoid.

I got instructions on how to do this, so I will try tomorrow.

[dieselbenz1]

Originally Posted by 903hblue

Yes, this is on the 1993 300d. You mean a volt meter?

Nope a remote switch.

[Junkman]

Originally Posted by tyl604

Jump the starter. If it is like the 126, you can do it with two screwdrivers using the wiring on the passenger side fender well. Forget which two screws you touch with the screwdrivers but it is really easy.

If that works, you may have a bad starter solenoid.

I just looked in my maintenance manual. For a 123:

There are 3 wire terminals near the coolant overflow bottle on the passenger side of the engine compartment that come into a plastic junction box. Connect the left and center terminals with a heavy jumper wire or 2 screwdrivers or whatever. The engine should crank regardless of any other switches that are open ie, ignition, neutral safety switch etc.

I use these terminals with a remote start to turn the engine when adjusting the valves. Connecting the wrong terminals hasn't messed anything up on either of my SDs.

[903hblue]

Originally Posted by Junkman

I just looked in my maintenance manual. For a 123:

There are 3 wire terminals near the coolant overflow bottle on the passenger side of the engine compartment that come into a plastic junction box. Connect the left and center terminals with a heavy jumper wire or 2 screwdrivers or whatever. The engine should crank regardless of any other switches that are open ie, ignition, neutral safety switch etc.

I use these terminals with a remote start to turn the engine when adjusting the valves. Connecting the wrong terminals hasn't messed anything up on either of my SDs.

I have a w124, but thank you, this sounds interesting. You can also do the same thing on the starter itself with a screwdriver.

[Maxbumpo]

There is also a connection point for the solenoid wiring near the brake booster, accessible from top. It is a three-pin connector, from foggy memory the middle pin is the solenoid wire connection between the ignition key and the solenoid. If you apply power here and nothing happens, the solenoid is dead. If you hear a "thunk" and then nothing happens, solenoid is probably good and the starter is bad, but further diagnosis is required. If you jump the big terminals on the starter itself and it spins without engaging, the starter electric motor is good. If you jump the battery side big terminal to the small terminal on the starter solenoid and get a "thunk" but no spin _or_ get nothing, the solenoid is your problem.

[903hblue]

Thank you.
Tried to jump it using a screwdriver at the starter. I got nothing but sparks making the connection to either post.

[Junkman]

What happens when you replace the small wire to the solenoid with another wire and touch the other end to the positive battery cable? Put an in-line fuse in your test wire.

Next step would be to pull the starter and bench test it.

[tyl604]

Try the screwdriver trick on the wheel well. Per Sixto: There's a junction block ahead of the battery and false firewall. Jump the starter pins (third and fifth??) to test the starter downstream of the NSS.

Thought I had a two screwdrive pic but could not find it.