74 Duster 340/904 - No Starter Power?

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zig

zig

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I am putting my car back together and having problems with getting power to the starter. I have a 340/904 combo installed. I am using the original ignition and wiring that came with the stock 318. I purchased a new mini starter and a new starter relay. I rewired to the diagrams posted previously to bypass the amp gauge per madelectric.com.

As you can see in the picture, I have the main power hooked to the large stud. I am using the plug from the main harness that does get 12v when the key is engaged and not when off. So this seems to be the ignition switch wire. Also plugged in is a plug from harness that goes to the neutral safety switch on the trans. That also gets 12v when key is turned on.

I have a manual and am studying the diagrams. That seems to be the correct wires to plug in. I also have most of the wiring hooked up otherwise. Just missing little stuff like horn, a/c, accessory stuff. I have power inside the car also, but little stuff like no lights working. Just power at the fuse box. I do not have any gauges hooked up yet or any switches. One other odd thing is the ballast resistor mounted on the firewall is getting warm when the key is on along with the coil. So now I am thinking I have something else wired incorrectly.

If someone can point me in the right direction I would appreciate it. This is the first car I've torn down and swapped motors. I am close to be able to start, but I thought I would see if the starter would at least engage, but nothing... I can move the engine by hand, so it's not locked up or interference...

Thanks...
2012-07-07_14-15-12_840.jpg
 
With the key in "run" the ballast will get warm. Don't leave it on, or unhook either side while testing to disable that circuit

ONE COMMENT It is difficult to tell from the photo, but to me, the main battery and starter cables look WAY TOO SMALL. Do you know what gauge wire they are? Original battery cables should be no4 OR LARGER

You may have mis - stated, but the push-on terminal at top left of relay should NOT be hot with "key on" but rather "key twisted to start." But it appears to be yellow? which would have been originally correct So use a test light and confirm that, IE should be hot ONLY with twisted to start

When you check that, also check the other push on going to the neutral safety. IF you have power there "in start", then it's not getting a ground, and that wire, or the switch or transmission is the problem

You can check the relay, make sure you are in park or neutral.

Pull the top left "start" wire off. Jumper from that relay terminal to the battery stud. The relay should engage and the engine should crank

If not, pull the NSS wire off the bottom left terminal, and clip that terminal to ground. Again, jumper the top left terminal to battery. The engine should crank. If not,

The battery lead to the relay is too small

the relay is bad

the starter wiring is bad

The starter is bad

So now jumper across the two large exposed terminals on the relay. The starter should crank

If it does, the relay is bad

If it does not you have (for now) eliminated the relay


Now move down to the starter. Jumper across the two starter terminals. The engine should crank

If so, You have a bad relay - solenoid wire

If not, you have

A bad battery cable

A bad starter

To check the battery cable, start by putting your meter, or even a test lamp, clipped to ground, and to the battery stud on the start relay. Once again jumper across down at the starter. IF the test light goes very dim, or the voltmeter goes below 10V, You have found the area of the problem.

Now "rig" some clip leads on the starter terminals so you can access them. Use the heavier size from Radio shack, or make some out of no 14 wire OR buy yourself a "remote starter switch" and clip to the starter terminals.

OK, Now start with the battery

Stab your probes directly into the battery posts, hold down the remote switch, and read voltage. Should be above 10.5V ALL THE FOLLOWING tests are with the starter "trying to engage" with a remote starter switch

Move one probe from the post to one clamp. Above 10.5

Move second probe to remaining clamp. Above 10.5

Move ground probe to engine block. Above 10.5

Now with probe on engine block, and hot probe on the starter relay battery stud, should still be above 10.5

Now clip your "hot" probe down onto the starter battery stud. Still should be above 10.5

If all this is OK, the battery voltage and cables are OK, and you have a bad starter

NOTE You can MAKE a remote starter switch, or buy one at the parts store. You need a good heavy generic starter switch like this:

http://www.northerntool.com/images/product/images/96753_lg.jpg

Use some big wire, no 12 is good, about 4 ft long, and put some good heave alligator clips such that you can hook to the two starter terminals

You want the kind that look like these, in a fairly small size, not like would be on a battery charger

http://img3.fastenal.com/productimages/0745903.jpg

While you are at it, get some conventional alligator clips and make up two or three long no 14 clip leads about 3-4 ft long

http://www.sz-wholesaler.com/userimg/505/506sw2/alligator-clip-699.jpg

You should be able to get all this stuff at any decent auto parts store.

For "everyday" clip leads and troubleshooting, go down to Radio Shack and pick up a couple of bags of their large size alligator clip leads, a package of extra clips, and a package of their "next size down" clips. This whole deal will cost you a 20, but it is WORTH having for chasing gremlins.

I assume you already have a light and meter
 
The yellow wire has been addressed, should only be hot with key in start position.

The wire from the NSS should not show voltage. It should be a ground circuit only. Disconnect that terminal, and ground the relay tab directly to the batt neg. See if that gets the starter live. If it does that may be your issue. Engine ground wires attached?

You can jumper the large post where the battery leads attach to the relay and the squarish terminal post/wire to the starter. If you jump that the starter should crank. If you have a remote start button, attach to those two terminals.
 
Being a 74 model with original wiring the seatbelt interlock is most likely culprit.
Buckle the seatbelt and try to start it.
 
Thanks for the quick replies. I was out there messing around again. I noticed the instructions that came with the starter relay state to attach ground to bottom prong. I grounded the relay and now have the starter working. I am one step closer to starting the engine...

I am going to go through the wiring again to make sure. I have a few extra wires here and there, need to follow my manual and see where they all go.

The battery cables are brand new reproductions and are the same size as the originals. I do have the battery cable wired as it was before. The only thing I changed was eliminating the amp meter and wiring the alternator directly to the starter relay per some previous discussions.

I've got plenty more wiring for electric fan and other gauges..

I am happy it is coming along... Need to have it ready for the Woodward dream cruise...
 
If you grounded the bottom prong and it started with your key, you likely need a new NSS in the trans or it needs adjusting.

Make sure the trans is in p or n. Check the center pin for ground to the case when in P/N. If it doesn't have continuity, there's your issue.
 
crackedback said:
If you grounded the bottom prong and it started with your key, you likely need a new NSS in the trans or it needs adjusting.

Make sure the trans is in p or n. Check the center pin for ground to the case when in P/N. If it doesn't have continuity, there's your issue.
Click to expand...

Yup
 
Check continuity of the wire from the NSS to starter relay. Seen more than one that insulation looked OK, but, the wire inside was corroded/broken.

If you do have the seat belt interlock system, bypass it with a jumper wire where it plugs in under the seats.
 
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