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115 240D starter problems

Submitted by jfields on 10 February 2007 - 5:26pm.
Have a 1975 240D that I just updated to the newer Bosch pencil type glow plugs and am having starting problems. I replaced the loop style plugs and removed the grounding strap on the first plug and am using the original starter pull switch. The kit came with a relay but I'll be damned if I can figure out how to wire it into the older system. If the car is left alone for a couple of hours it fires right up, subsequent attempts to start it fail though. When I pull the starter knob nothing happens, no clicking from the starter motor it's just dead. Battery has a full charge and is a new Bosch unit and I've checked all the grounds and they seem to be fine as well. Is it possible something is either shorting out or maybe my pull switch is going. Was there something else I need to do to insure the new glow plugs are correctly installed, did I miss a connection? Kind of at my wits end. Going to replace the + battery terminal wire tomorrow any other ideas would be a great help. The newer plugs really are great as when it does fire up it kicks in on the first pull. Used to take about three or four tries with the older loop plugs.
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Trace your electrical current

10 February 2007 - 9:10pm
Kent Bergsma

You most likely have a bad pull switch or bad starter motor (provided you have first made sure your grounds are clean and tight (including the ground cable between the engine and the body)and the wires to the starter motor are clean and tight.

To determine the culprit, you will need a voltmeter to test for 12 current at key points is the starting circuit. Have someone engage the starter switch while you check for power from switch to the starter solenoid (small wire). If you have power to the solenoid then you can rule out the pull switch. Try tapping on the starter with a long metal rod. If it immediately turns over - replace or rebuild your starter. (we have good used ones on our website).

If no power to the starter then suspect the switch. Don't just assume that is the problem. You may have a wiring problem that is preventing power from getting to the switch. We carry a new switch on our site for a very reasonable price.

Let us know how you solve your problem

Kent Bergsma

Looks like I'm getting another voltmeter...

10 February 2007 - 9:47pm
jfields
I'll check out the key points and report back, already ordered the new pull switch from you on Friday night. Even if it's not the switch I figured it would be good to have a spare. I'm sure I'd have this problem licked if it wasn't 23 degrees here during the day. Brutal on the hands.... Thanks! Joshua

Fixed it!

11 February 2007 - 1:31pm
jfields
Turns out there was a short to the starter, wires had been baked to death over the years so I replaced the toasty ones going to the starter solenoid and the positive battery cable and all was well. Did a diesel purge after that and she's running like a top. I ordered your fuse replacement kit as well, mine are looking a bit crusty. Thanks for the help!