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  #1  
Old 07-24-2006, 11:46 AM
Tabor
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Car Won't Start When Hot: Starter Doesn't Turn - Not The Starter

I posted this thread a while ago: Car Won't Start When Hot: Starter Doesn't Turn. I have since replaced the starter. It was not the starter.

The problem has now gotten much worse. More often than not, the car won't start. I have discovered that placing the ignition key in the on position and running positive power from the battery to the starter (solenoid) will start the car.

So, I think it comes down to one of three things: wiring, ignition switch, and the neutral safety switch in the transmission.

I am pointing my finger at the neutral safety switch (NSS).

Which wires connect to the NSS? That is, laying no the ground, looking at the transmission, how do I identify the NSS?

TIA

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  #2  
Old 07-24-2006, 12:15 PM
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its on the side of the transmission...looks like this

[IMG]http://www.***************/secure/PartImages/0005454906.jpg[/IMG]

I had mine break a while ago...the car wouldnt start...yet if i put the key in..turned it on...popped the hood and jumpered the start it would start...

that sounds like your culprit..i believe its on the driver's side of the trans...the shifter linkage runs though it....

to remove...rotate white clip..pull plug...remove linkage from nss...unmount nss..and there u go

hope this helps


kris
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  #3  
Old 07-24-2006, 12:20 PM
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Crawling around underneath, neutral safety and reverse lights combo switch will be the electrical hookup on driver's side. Degreasing, unplugging and replugging it might help. Also try working the tranny through the gears, sometimes the car might start in N but not P. And try wiggling the shifter in P or N while turning the key.

The fact that this problem has gradually gotten worse instead of just suddenly dying could indicate slow mechanical failure of the NS switch, i agree with you that's probly the place to start.

And turning the key makes electrics come on and glow plugs heat up, correct? This should indicate the key switch is okay.
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Old 07-24-2006, 12:29 PM
Tabor
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Quote:
Originally Posted by 240DieselDog
Crawling around underneath, neutral safety and reverse lights combo switch will be the electrical hookup on driver's side. Degreasing, unplugging and replugging it might help. Also try working the tranny through the gears, sometimes the car might start in N but not P. And try wiggling the shifter in P or N while turning the key.
This would explain why the guy at the part store could find the NSS but not the reverse light switch. I ordered the NSS one minute ago. The reverse lights have never worked on this tranny, I have a used NSS, but a new NSS+reverse light switch was only $31.

Quote:
Originally Posted by 240DieselDog
The fact that this problem has gradually gotten worse instead of just suddenly dying could indicate slow mechanical failure of the NS switch, i agree with you that's probly the place to start.

And turning the key makes electrics come on and glow plugs heat up, correct? This should indicate the key switch is okay.
Every idication I have says the ignition switch is fine (glow plug light, etc). However, running the shifter through the gears has NEVER helped. I will see if the NSS fixes it. If not, I will attack the ignition switch.
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Old 07-24-2006, 12:54 PM
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You need a "HARD START" relay. With the car being 28 years young, the wiring, ignition switch gets resistance and/or poor contacts. The relay takes the load off of the ignition switch. Try the NSS but if it still doesn't start hot, let me know. The relay is easy to do and total cost is about $20-$25. Chris
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Old 07-24-2006, 01:03 PM
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Quote:
Originally Posted by Motorhead
You need a "HARD START" relay. With the car being 28 years young, the wiring, ignition switch gets resistance and/or poor contacts. The relay takes the load off of the ignition switch. Try the NSS but if it still doesn't start hot, let me know. The relay is easy to do and total cost is about $20-$25. Chris
I'm interested in this hard start relay. Can you tell me more? What exactly is it -- relay inbetween ignition switch and starter? I have an 85 SD with similar NSS problems and regularly jumper it off the nice black box with 4 wires they put under the hood. Starter seems to crank better. I believe this is there for mechanics to turn the engine easily and various things. I want to wire one of these to my 1981 300D NA that does not have one. Is it pretty simple? 1 wire to starter to box, another wire from battery to box . Then just jumper them when i need to?
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  #7  
Old 07-24-2006, 01:07 PM
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How's your ground? There's a huge but short ground strap that goes from under the head of the screw that holds on the starter to a solid point on the body. Without this strap clean and tight, all other efforts will be largely futile.
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  #8  
Old 07-24-2006, 01:38 PM
Tabor
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Quote:
Originally Posted by Pete Burton
How's your ground? There's a huge but short ground strap that goes from under the head of the screw that holds on the starter to a solid point on the body. Without this strap clean and tight, all other efforts will be largely futile.
It is fine. In fact, it is the first thing I checked.

However, if it were the ground, I doubt it would start when jumpered.
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Old 07-24-2006, 03:51 PM
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OK, then how about the cable to the starter? You've probably checked this too, but I've had several difficult to find electrical problems in my wrenching days, and more often than not, there was a failure somewhere in a large cable that I had checked several times, but not carefully enough.
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  #10  
Old 07-24-2006, 11:16 PM
Tabor
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Update

I believe it was the connection to the NSS. After replacing the NSS I suddenly had reverse lights, but still no start. So, I took the connector off and carefully examined it. One of the female connections was WAY too sloppy. I tightened it down with some pliers and now everything is back to normal AND I have reverse lights!
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  #11  
Old 07-25-2006, 09:21 AM
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Try starting it after pulling the brown vacuum line off the shut down switch on the rear of the IP, that would eliminate the ignition switch.

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