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Old 12-17-2016, 05:42 PM   #1
bhayes1
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No juice to starter

Real quick...

I just swapped motors in my truck and I'm trying to start it for the first time and nothing...

I've got a wire coming from the main harness off the hot side of the battery that is hot when the key is on and I don't recall where it went. No juice to the coil at this point. I know this has got to be the culprit but I can't for the life of me remember where it went.
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Old 12-17-2016, 05:50 PM   #2
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Re: No juice to starter

Very small gauge wire
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Old 12-17-2016, 07:59 PM   #3
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Re: No juice to starter

it goes to a stand off block on the pass fender where there is another wire affixed if thats the wire you're talking about....
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Old 12-17-2016, 08:59 PM   #4
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Re: No juice to starter

A few more pieces to the puzzle:

The red wire is the one I am speaking about in my original post. It has a female spade terminal which you think it would be a dead give away on where it goes. Again, it is hot when the key is in run and cold when the key is off and currently my test light is showing no power to the hot side of the coil when the key is in run.

Don't recall what the blue wire and yellow wires are either? It is coming from the same group of wires that stater wires are in.

I've got two starter wires. I am fairly confident the starter is wired correctly. It is a high torque mini starter so I have the large terminal hooked directly to the hot side of the battery. I've got one of the smaller wires to the small terminal and the other gets taped up and goes unused.

It all worked when I pulled it...
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Old 12-18-2016, 11:58 AM   #5
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Re: No juice to starter

Bueler
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Old 12-18-2016, 04:33 PM   #6
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Re: No juice to starter

I suspect with the deep freeze across much of the U.S., and it being Christmas, you're likely to get few responses.

My material is not available at the moment, so I'll give you my $0.02 without those aids.

But, looking at your pictures, it seems your engine room wiring has been "modified".

So, no power to the starter nor to the coil? Let's take this one step at a time.

1. The engine has a large gauge wire connecting it to the negative terminal on the battery?

2. The starter solenoid has a large gauge wire connected to the positive terminal on the battery?

3. The starter solenoid has a small gauge wire connected to the "start" position of the ignition switch? Keep in mind, on the stock starter, there were at least two small terminals. One goes to the coil during starting. (We'll not worry about that terminal at the moment, just make sure you connect the correct terminal to the "start" position on the ignition switch.)

That should get the starter cranking. The next set is to set up the coil.

4. The coil "negative" should be connected to the points, or points equivalent in the distributor. If your distributor has an electronic points replacement module, it'll need power!

5. The coil "positive" needs to be connected to the "on" position on the ignition switch. However, with most coils, to prevent excessive current from damaging the points, some sort of ballast resistor must be used. The stock wiring had a length of resistance wire in lieu of a ballast resistor. If your resistance wire has been replaced with a conventional wire, you'll have to provide a ballast resistor unless there is no need for it.
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Old 12-18-2016, 07:46 PM   #7
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Re: No juice to starter

Magma, Thank you for the detailed response.

The entire harness has been "heavily modified" to put it nicely, unfortunately. The truck has an MSD box and electronic ignition.



Quote:
1. The engine has a large gauge wire connecting it to the negative terminal on the battery?
Yes, the engine is grounded to the battery.

Quote:
2. The starter solenoid has a large gauge wire connected to the positive terminal on the battery?
Correct.

Quote:
3. The starter solenoid has a small gauge wire connected to the "start" position of the ignition switch? Keep in mind, on the stock starter, there were at least two small terminals. One goes to the coil during starting. (We'll not worry about that terminal at the moment, just make sure you connect the correct terminal to the "start" position on the ignition switch.)
There is some grey area here, let me try and explain.

Yes, because it is an aftermarket starter it only has the main terminal for the positive battery cable and one other small terminal for the ignition start position wire.

Is there a sure way to test which wire is my ignition start position wire? I am fairly confident but would like to be 100%.

Lastly, My starter worked perfect when I pulled it out. I do not have any reason to believe that it shouldn't work now. However, in the troubleshooting process I pulled the starter inspected it and tried to take a hot battery and some jumpers to verify the motor and bendix were engaging and I couldn't make it work. Shouldn't I have been able to jumper the small terminal and larger terminal together and put a 12v battery to it and get it going out of the truck? Something there doesn't make sense to me.

Quote:
That should get the starter cranking. The next set is to set up the coil.
I believe I met all the above and no go so far...

Quote:
4. The coil "negative" should be connected to the points, or points equivalent in the distributor. If your distributor has an electronic points replacement module, it'll need power!
Yes electronic, and no power at the moment. (thought this is where my missing red wire would solve the problem?

Quote:
5. The coil "positive" needs to be connected to the "on" position on the ignition switch. However, with most coils, to prevent excessive current from damaging the points, some sort of ballast resistor must be used. The stock wiring had a length of resistance wire in lieu of a ballast resistor. If your resistance wire has been replaced with a conventional wire, you'll have to provide a ballast resistor unless there is no need for it.
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Old 12-18-2016, 08:07 PM   #8
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Re: No juice to starter

Have some one help You with the ignition switch, use a volt meter or 12 volt test light to check the smaller wires--that should tell you something! Constant voltage to ignition and momentary voltage to starter!
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Old 12-24-2016, 11:04 PM   #9
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Re: No juice to starter

Update -

Okay so I'm halfway to figuring out the mystery. Upon installing the (new to me) engine it has taller valve covers than the last set. Because the valve covers were taller they came in contact with with the hot terminal on the alternator (serpentine setup) and did some damage to various electrical components. It burnt a wire in my starter which is why I wasn't getting any juice. Made the simple repair and now I've got the engine turning over so that's a good sign.

From there I went on to check for power at the distributor.... Nothing. So I went inside the cab and pulled the ignition switch and it is getting power to the switch and I have power leaving the switch. Then, it started dumping down rain before I could do more testing so that is where I am at for now.

Thinking my next thing to do will check to see if I have power before and after the msd box.

If for some reason I screwed up the MSD box how hard would it be to bypass this? I have zero need for it with my current setup....

I'll keep you posted.
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Old 12-25-2016, 12:44 AM   #10
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Re: No juice to starter

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I'm coming in late here so I'll see if I can add a couple of things. If it hasn't been replaced with another color the heavy gauge Purple wire (10 or 12 gauge if I remember right) connects to the "S" terminal on the solenoid. If there is a smaller Yellow wire you may not need it with electronic ignition. The colors can be hard to see down by the starter so follow them up by the firewall to check the colors.

Is your distributor an HEI or points with some kind of aftermarket unit? I don't know anything about MSD stuff..

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Old 12-26-2016, 01:15 PM   #11
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Re: No juice to starter

Quote:
Originally Posted by bhayes1 View Post
A few more pieces to the puzzle:

The red wire is the one I am speaking about in my original post. It has a female spade terminal which you think it would be a dead give away on where it goes. Again, it is hot when the key is in run and cold when the key is off and currently my test light is showing no power to the hot side of the coil when the key is in run.

Don't recall what the blue wire and yellow wires are either? It is coming from the same group of wires that stater wires are in.

I've got two starter wires. I am fairly confident the starter is wired correctly. It is a high torque mini starter so I have the large terminal hooked directly to the hot side of the battery. I've got one of the smaller wires to the small terminal and the other gets taped up and goes unused.

It all worked when I pulled it...
The red wire might be for the ignition. Did you check to see if it has power when the key is on? The second pic shows your oil pressure switch for a light.
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Old 12-30-2016, 11:37 AM   #12
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Re: No juice to starter

Just wanted to give a conclusion to this thread and say thanks to those who helped.

As stated above, I had a bad internal connection in the starter that really made me scratch my head. I'm thinking this was because of the self inflicted short I caused (touching the hot alternator terminal to the taller valve covers).

Once I got the truck to turn over I still couldn't get my 12 volt test light to show the coil was receiving power and here is the reason:


Quote:
With a CD ignition installed it is normal NOT to see voltage at the coil with a voltmeter or test light. The only way you will be able to test the voltage at the coil will be to use a scope with a 100x probe.
This came off of the MSD site from tech support from a previous guy asking the same question.

Once I read this I went ahead and pulled a spark plug and sure enough I am getting a good spark.


It's always hard to troubleshoot when the PO has made modifications from stock, but I learned a few things about my truck. A little frustrating but I guess that is to be expected for a rookie doing a first time engine swap. Still need to button up a few things and she should be back on the road this weekend.
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