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914-8 |
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#1
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
The engine and trans were out for restoration work, of course, the wiring was all disconnected. Small block Chevy.
The engine and trans are back in the car now, but the starter won't turn and the fuel pump won't pump. Here's a diagram of the setup: (IMG:http://img.photobucket.com/albums/v520/bak535/Picture168.jpg) Here's a pic of the alternator before I took the car apart: (IMG:http://img.photobucket.com/albums/v520/bak535/Picture031.jpg) (It seems odd that the red wire comes out of the white 2 wire connector on the alternator, then attachs to the post on the outside of the alternator. Why would they do that? Why wouldn't that connection just be made internally?) Here's the situation: 1. All the general electrical works - all exterior lights, wipers, interior lights, gauges, turn signals, etc. 2. But the starter won't turn over. I measured 12.6 volts at the starter, from the battery. When I turn the ignition switch to "on," I get 12V at the yellow wire connection on the starter. So it should turn over, right? But it doesn't. When I try to ground the 2 connections at the starter (the stub where the yellow wire connects and the 12V connection), I get sparks, but no turnover on the starter. Does this end my analysis? Bad starter? Seems odd, because it was fine when I took it off the car. And it is the IHI starter that I understand rarely fails. 3. The other thing is the fuel pump, which is a Mallory. Normally, when the key is in the accessory position, I can hear the fuel pump running. Now it is not running. The odd thing is when I turn the key to the accessory position, the pump is getting voltage! I put a test light on it, and it turns on when I turn the ignition sw to accessory. But the pump is not pumping. Seems too coincidental that the starter AND the fuel pump have now died. 4. The car has an ammeter gauge in it. From what I recall, the gauge never really moved off of the "0" position in normal operation of the car. I don't think I ever saw it move, other than a tiny bit in one direction of another. With the car at rest, it reads 0. When I put the key in the accessory position, it moves slightly, like it always did. But when I try to start the car, the gauge pegs all the way to the right, which reads something like " -30 " (negative 30). It never did that before. This is a major clue, which I cannot interpret, because I'm not exactly sure what an ammeter gauge does, or what that reading means. I did have the wiring apart, and I could have miswired something when I put it back together, although I was pretty careful, with pictures, markers, diagrams, etc. I've tried starting the car while the battery is jumped to a running car, with the same results. Any ideas? |
John |
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#2
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member? what's a member? ![]() ![]() ![]() ![]() Group: Members Posts: 3,393 Joined: 30-January 04 From: Evansville, IN (SIRPCA) Member No.: 1,615 Region Association: None ![]() |
Try tapping on the starter. It sounds like it is stuck to me. You did get the trans ground strap reinstalled?
Check your grounds. Don't know about the fuel pump yet..... |
Tom |
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#3
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None ![]() |
914-8
The yellow wire should only have voltage when you turn the key to start. Sounds like some thing got mixed up here. That yellow wire is the wire that tells the solenoid to close and make the starter contacts so the starter motor will turn over. That solenoid does double duty, it throws out the starter shaft and gear to engage the flywheel and at the same time makes contact between the batt post on the solenoid and the motor post on the solenoid allowing the starter motor to spin, turning over the engine. Hope this will help. Tom |
Crazyhippy |
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#4
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Insert witty comment here... ![]() ![]() ![]() Group: Members Posts: 1,659 Joined: 28-July 05 From: Home of the Coyotes, AZ Member No.: 4,493 Region Association: None ![]() |
Use a test light instead of a Voltmeter... Make sure there is some current @ the starter (check both the big red and the small yellow which should be only w/ the key in the start position).
Can run a temporary jumper wire direct from the battery to the spade where the yellow wire hooks up, to check if the starter is good. Then the fuel pump... again use a test light and check that there is juice to it... Beyond that, double check all the connections, and the ground points. BJH |
SLITS |
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#5
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"This Utah shit is HARSH!" ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None ![]() ![]() |
2. But the starter won't turn over. I measured 12.6 volts at the starter, from the battery. When I turn the ignition switch to "on," I get 12V at the yellow wire connection on the starter. So it should turn over, right? But it doesn't. When I try to ground the 2 connections at the starter (the stub where the yellow wire connects and the 12V connection), I get sparks, but no turnover on the starter. Does this end my analysis? Bad starter? Seems odd, because it was fine when I took it off the car. And it is the IHI starter that I understand rarely fails. 3. The other thing is the fuel pump, which is a Mallory. Normally, when the key is in the accessory position, I can hear the fuel pump running. Now it is not running. The odd thing is when I turn the key to the accessory position, the pump is getting voltage! I put a test light on it, and it turns on when I turn the ignition sw to accessory. But the pump is not pumping. Seems too coincidental that the starter AND the fuel pump have now died. 4. The car has an ammeter gauge in it. From what I recall, the gauge never really moved off of the "0" position in normal operation of the car. I don't think I ever saw it move, other than a tiny bit in one direction of another. With the car at rest, it reads 0. When I put the key in the accessory position, it moves slightly, like it always did. But when I try to start the car, the gauge pegs all the way to the right, which reads something like " -30 " (negative 30). Any ideas? The motor on the starter could be burned out. Jumping the two LARGE terminals should make the starter motor run (but won't extend the bendix drive) assuming you have a good ground. The motors and solenoids DO GO BAD. The -30 on the amp meter is an indication of direct short ... it should have fried your wiring. The short could be in your starter. Check your positive leads to the starter and fuel pump for grounding. |
914-8 |
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#6
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
914-8 The yellow wire should only have voltage when you turn the key to start. Sounds like some thing got mixed up here. That yellow wire is the wire that tells the solenoid to close and make the starter contacts so the starter motor will turn over. That solenoid does double duty, it throws out the starter shaft and gear to engage the flywheel and at the same time makes contact between the batt post on the solenoid and the motor post on the solenoid allowing the starter motor to spin, turning over the engine. Hope this will help. Tom Yes, testing with a test light, I can see that the yellow wire connection on the starter is only getting 12V while the key is in the start/cranking position. So the yellow wire is working properly. |
914-8 |
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#7
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
Use a test light instead of a Voltmeter... Make sure there is some current @ the starter (check both the big red and the small yellow which should be only w/ the key in the start position). Can run a temporary jumper wire direct from the battery to the spade where the yellow wire hooks up, to check if the starter is good. Then the fuel pump... again use a test light and check that there is juice to it... Beyond that, double check all the connections, and the ground points. BJH Tried with a test light. Getting constant current at the starter at the big red connection (connects directly to the + post on the battery), and current at the yellow wire only when the key is in the start position. |
914-8 |
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#8
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
The motor on the starter could be burned out. Jumping the two LARGE terminals should make the starter motor run (but won't extend the bendix drive) assuming you have a good ground. The motors and solenoids DO GO BAD. The -30 on the amp meter is an indication of direct short ... it should have fried your wiring. The short could be in your starter. Check your positive leads to the starter and fuel pump for grounding. I suppose the starter motor could be burned out - although it was working fine when I took it off the car to begin the project a month ago, and it has been doing nothing but sitting inside the house for a month. Jumping the two large terminals - I'm not sure which ones you're talking about. You mean the one that connects directly to the battery, and the one under the bottom round blue cover in this picture: (IMG:http://i16.ebayimg.com/01/i/08/91/ae/36_1.JPG) -30 being a direct short - hmmm, that doesn't sound good. No fried wiring that I can see anywhere. On the IMI starter like in the picture, there are only 2 connections, like in my hand drawn diagram above, correct? |
SLITS |
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#9
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"This Utah shit is HARSH!" ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None ![]() ![]() |
Ok, the purple lead from the solenoid to the body of the starter is your motor power.
There are normally three poles on the starter assembly: 1.) A biggun from the battery to the solenoid. 2.) A biggun from the solenoid to the body of the starter (motor power) 3.) A spade or screw terminal on the solenoid to accept switched power from the key. Jumping 1 & 3 causes the bendix drive to jump out an engage the flywheel and turn the motor. Jumping #2 & #3 sends power directly to the starter motor windings and causes the starter motor to spin only without engaging the flywheel. Actually, to test the starter motor .... pull it off the car ..... hook it to a battery charger (or battery) .... + lead to the solenoid where the battery would normally connect and - lead to the starter housing. Jumping the big pole and spade terminal on the solenoid should cause the bendix to extend and the motor to whir. If it doesn't, the starter is bad (internally shorted or grounded). Oh, BTW and alternator must be "excited" to make voltage. As I remember, the field? coils are "excited" by a connection between the battery and the alternator. On the 4 cylinder, this is accomplished by a lead from the battery to the battery connector on the starter solenoid which another wire (with ring terminal) runs to the B+ pole on the alternator (this is part of the /4 alternator harness). |
914-8 |
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#10
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
Here's some more pics of the starter setup.
(IMG:http://img.photobucket.com/albums/v520/bak535/Picture170.jpg) Here's the only 2 wire connections. The black wire on top goes directly to the + post on the battery. The bottom wire is the yellow from the ignition switch. Not a lot to miswire here! (IMG:http://img.photobucket.com/albums/v520/bak535/Picture174.jpg) I did manage to fix, though! John had it right with the first post. I tapped on the starter a few times with a hammer, and it cranked right up! The hammer - such an underrated automotive tool. Thanks everyone! (IMG:style_emoticons/default/aktion035.gif) |
Crazyhippy |
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#11
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Insert witty comment here... ![]() ![]() ![]() Group: Members Posts: 1,659 Joined: 28-July 05 From: Home of the Coyotes, AZ Member No.: 4,493 Region Association: None ![]() |
How about the fuel pump?
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914-8 |
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#12
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
How about the fuel pump? Sheesh, don't I get a few minutes to bask in the glory of the starting starter! (IMG:style_emoticons/default/biggrin.gif) The starter had me most worried, because of it's connection with various other systems, and because I hate not knowing what's wrong or how it is going to be resolved (I get fixated on it) so I'm relieved to have that fixed. The fuel pump is just 2 wires, 12V in and a ground. So I know if it's getting 12V but not pumping, it has to be something internal in the pump, and the worst case scenario is I just buy a new one. It's 12 years old . . . so it's done it's time. Although I think it has the same problem the starter had. After sitting off the car for a month, it's frozen up a bit inside somewhere. I'm wondering if maybe I can take it apart, clean it out, and put it back together. Here's the pump. (IMG:http://img.photobucket.com/albums/v520/bak535/Picture175.jpg) |
914-8 |
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#13
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
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Crazyhippy |
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#14
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Insert witty comment here... ![]() ![]() ![]() Group: Members Posts: 1,659 Joined: 28-July 05 From: Home of the Coyotes, AZ Member No.: 4,493 Region Association: None ![]() |
Get a hammer.... (serious)
tap tap here, a tap tap there.... |
SLITS |
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#15
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"This Utah shit is HARSH!" ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None ![]() ![]() |
Maxwell's Silver Hammer will fix anything!
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BMITCHELL |
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#16
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Member ![]() ![]() Group: Members Posts: 328 Joined: 28-February 05 From: Moorpark, CA Member No.: 3,681 ![]() |
Remember to take your hammer with you if you don't change the starter. They have been known to develope a flat spot on the armature.
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John |
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#17
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member? what's a member? ![]() ![]() ![]() ![]() Group: Members Posts: 3,393 Joined: 30-January 04 From: Evansville, IN (SIRPCA) Member No.: 1,615 Region Association: None ![]() |
Remember to take your hammer with you if you don't change the starter. They have been known to develope a flat spot on the armature. This is true, but hopefully it was just a stuck bendix or solenoid from sitting. When they get a flat (or dead) spot you hear the bendix pop out (clunk) but no spinning. Please use a soft face hammer when tapping on motor housings.... Check the amp draw on the fuel pump to make sure it is really drawing a bunch of amps. If it does draw lots of amps, it's stuck. If not, it's probably a bad connection somewhere. Good luck to you. just my $0.02 |
914-8 |
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#18
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Senior Member ![]() ![]() ![]() Group: Members Posts: 802 Joined: 23-January 06 From: Cal Member No.: 5,461 Region Association: None ![]() |
I bench tested the fuel pump, yeah, it's drawing a ton of amps, so something's going on inside.
The Magic Hammer didn't fix it. I'll probably just replace it, given that it's 12 years old and unlike with a starter, a pump failure on the road means "no go." Plus it's easier. And a shiny new pump will match my other shiny new stuff. |
spoon |
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#19
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Newbie ![]() Group: Members Posts: 1 Joined: 24-February 07 From: Monterey, CA Member No.: 7,559 ![]() |
Where is the fuel pump relay located on a '72 914 1.7L?
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