Intermittent starting problem

[Steeveedee]

Originally Posted by VetteVet

Well maybe:
If you jumped the ignition switch when it was in an intermittent phase and not working and then it worked when you jumped the switch, I'd agree. I'm thinking that's the case. Otherwise there's the possibility that it might be the neutral start switch not closed by the position of the gear selector, or the connection between the purple wires in the firewall block behind the fuse block.

It might be worthwhile to wait until the no start happens again and then jump to the ignition side of the neutral start switch. Don't bump the shift lever and if the starter turns it confirms that the key switch is bad. If not jiggle the shift lever and see if the starter turns then.

It is quite common for the NSS to get out of adjustment or wear down where it won't close the circuit between the purple wires.

Yup. Good diagnostic tip! I personally do not like to replace parts until the problem is properly diagnosed. I worked as a mechanic for many years, and the customers take a dim view of this, since they are paying for parts that didn't need to be replaced. The people who do this are called "parts changers", and are the bane of mechanics and their customers, world wide. Back in the day, if the coil got replaced unnecessarily, it was kind of bad. Now, when each electronic component costs something like a month's mortgage or rent, it is especially important to get it right.

[dzbowtie]

I know this thread is a couple months old at this point, but just to recap:

at times, the starter does not want to turn over, almost like a dead battery. the red brake light in the dash will come on.

I tested with a jumper wire, the power wire and ignition wire at the starter...the starter will turn over.

when I would attempt to start the truck with the key, I could hear a click but nothing happens. almost like the starter is stuck.

at this point, I used the jumper wire on the back side of the ignition, which the same happens. I could hear a click, but no turning of the starter.

I hooked a push button to the starter with alligator clips, bumped it over 1 time.

from there, I could start the truck with the key. almost like the starter was stuck, but once bumped over with the push buttom, the key ignition worked.

vettevet, help me out here!!!

thank you

[davepl]

Sounds like I already covered this exact problem in my manifesto about the Purple Wire.

Your solenoid circuit has too much resistance in it. Bad switch, neutral safety, or far more likely, a bad splice in the purple wire.

[dzbowtie]

Dave,

Would this explain why, when this happens, I can put jumper cables in from another vehicle and she fired right up with no issue every time?

If the purple wire is the culprit, is there anything I can do to help until the wire can be replaced?

Thanks again

[cleszkie]

Originally Posted by dzbowtie

If the purple wire is the culprit, is there anything I can do to help until the wire can be replaced?

Thanks again

Install a Ford solenoid LOL.

[leftybass209]

New parts don't necessarily equal good parts. Getting a "click" sound (from any component that doesn't function) simply means there's not enough current supplied to operate it efficiently, or the component is broken.

The current issue can be caused by either a resistance that's too high, or not enough current from the battery.

High resistance can be caused by bad connections, old wiring, brittle wiring which may be broken under the conduit, corrosion which may not be seen, especially if it's crept under the conduit. It can also be caused by a mechanical fault. If you have anything worn in the engine, or the starter, it increases mechanical resistance which puts a larger strain on the battery, increasing the amperage to start the vehicle.

A good battery is 12.65+ volts DC. A battery that reads even 12.40 volts, is only 75% charged. However, that is only the voltage provided, not the current. The battery must be load tested to find out if it truly is good. A proper load test should be done to half the CCA of a battery 2 times for 15 seconds each. Wait 30 seconds for the battery to recover, and the battery should read 9.6 volts or higher. Walk your local auto parts guys through the process as they probably don't know the proper way, because they load test dead batteries all the time without properly charging them, then incorrectly tell the customer the battery tested bad.

You can do a voltage drop test on your battery cables as well.

1. Disable the ignition or fuel system on the truck. Fuel is better because it doesn't flood the cylinders, but harder unless you have an electric fuel pump in which case, remove the fuse and start the truck until it dies.

2. Connect one lead of the voltmeter to the starter motor battery terminal and the other end to the positive battery terminal.

3. crank the engine and observe the reading while cranking. (disregard the first higher reading.) The reading should be less than 0.20 volts (200 millivolts)

4. If accessible, test the voltage drop across the "B" and "M" terminals of the starter solenoid with the engine cranking. The voltage drop should be less than 0.20 volts (200 millivolts).

This test can be done from the batt. terminal to the connection on the cable. From one end of the cable to the other end of the cable, or from the batt. terminal to the S. terminal on the starter. Each test tells you the resistance of that particular connection.
This test is only to check if the cables and connections are okay. A starter amperage draw test can determine if the starter motor is at fault, but requires a current draw tester such as a VAT 40/60 or the newer fancy Snap-on machines.

An 8 cylinder with typical compression should draw somewhere around 185-250 amps (normally less than 150 amps) at room temp.

Having said all this, I wouldn't suspect any of it is your problem. The start system on a classic vehicle is notoriously easy to work on. There are only 4 components and their associated wiring. Battery --> Ignition Switch --> NSS --> Starter solenoid. You've addressed the components, but the wiring is still old. I'd rewire it. All the parts to keep the wiring original can be found through various vendors.

It's also possible to do voltage drops on ANY of the wiring between any of the components. Higher volts or millivolts simply means increased resistance under load. It's such an underrated test but extremely effective.

Regarding Ford Solenoids. They are usually band-aids to existing problems. The GM starter system IS just as reliable as the Ford starting system. However, the Ford solenoid is usually implemented when people don't understand electrical systems, jump online or talk to a friend who suggests they pick up a "cure all" Ford style solenoid. They work, plain and simple. However, to use an instance that most people understand:

if I told you to wrap a leaky radiator hose with tape and it'd save you from having to replace the hose (supposing the tape would in fact cure it), would you Band-Aid it or correctly replace the hose?

[davepl]

Originally Posted by dzbowtie

Dave,

Would this explain why, when this happens, I can put jumper cables in from another vehicle and she fired right up with no issue every time?

If the purple wire is the culprit, is there anything I can do to help until the wire can be replaced?

Thanks again

I don't remember... I think jump-starting helped when it happened to me. It makes sense that it might bring up the cranking voltage enough that it can overcome a marginal solenoid circuit.

Basically, if you can start it by "hot wiring" the solenoid pole on the starter, then you know the starter and everything else is good, so it must be the circuit. So if you can start it with a screwdriver or jumper lead, that's a pretty good indication.

This happened to me 30+ years ago when I was 17. I had no idea what caused it, but for some reason turning the motor over by hand with the fan would sometimes help. Pouring water on the starter would help. Eventually we figured out the screwdriver trick and my passengers all got good at it.

Not sure how I finally figured it out. Ultimately the cause was a poor quality splice where I had tried to install an ammeter or kill switch or something. But about 3 years later my brother had a similar problem and the shop replaced a ton of parts, without luck, only to find out it was the same thing (purple wire!). So it's kinda stuck with me.

[dzbowtie]

thank you all for the help. i went the route with the remote solenoid. while i was rewiring everything, i had forgotten that i had a length of extra purple wire (approx 12 in) that was tucked into the wire channel at the top of the fire wall. this gave me plenty to work with as i rerouted it to the new solenoid, even trimming some off. i drove the truck around all day with no fail, firing right up each time.

[VetteVet]

Originally Posted by dzbowtie

thank you all for the help. i went the route with the remote solenoid. while i was rewiring everything, i had forgotten that i had a length of extra purple wire (approx 12 in) that was tucked into the wire channel at the top of the fire wall. this gave me plenty to work with as i rerouted it to the new solenoid, even trimming some off. i drove the truck around all day with no fail, firing right up each time.

There's a saying that "nothing succeeds like success".

Here's a solution for you naysayers to the Ford solenoid, Use a 30 amp Bosch relay which costs less than the ford solenoid.

Remember to disconnect the negative battery cable before doing any electrical work on your vehicle.




Take the purple wire off the solenoid and connect it to the 86 terminal on the relay. If you mount the relay close enough to the starter you may not have to extend the purple wire. Also the wire from the battery positive post can be run from the starter cable on the solenoid to terminal 30 on the relay. Then all that's needed is to run the purple wire from terminal 87 on the relay, over to the solenoid S terminal, and ground the 85 terminal on the relay.

You can't get any more current to the solenoid than this.
The relay only needs 1 amp to energize whereas the Ford solenoid needs 3 to 5 amps. Plus you won't have the purists griping about the Ford solenoid,

[MattyBs71]

DZbowtie - Have been dealing with this same issue for a few years it seems. Same exact issue. Replaced the ignition switch worked ok for awhile then same problem. Ended up wiring in a push button starter so key could be turned on and hit push button and it would fire everytime.... key intermittently no go no click nothing but power to everything but no crank. Well guess what happened? One day I go to leave for lunch break and smoke starts coming up out from under my dash, stop the truck in parking lot real quick turn key off and disconnect battery..... guess what's wrong? The plug that goes into the back of the ignition switch, it was worn inside and had corrosion and started melting. Replaced that plug and ignition switch again and no more problems. Soldered the connections traced the purple wire to make sure no cuts or breaks. Not one issue so far so good. The plug on back of ignition switch was my root cause I believe.

[davepl]

Originally Posted by MattyBs71

The plug on back of ignition switch was my root cause I believe.

Guess what wire goes through there? The purple wire.

I should go register PurpleWire.com :-)