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more electric stuff........


Guest chef tim
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Guest kelowna kid

Load testing battery is always a good idea but I doubt you have a shorted cell if you have 12ish volts(not running)Fully charged battery will be close to 12.5 volts.

Fully charged battery w/one shorted cell about 10.4, 2 shorted cells 8.3 etc.

More likely to be damaged by overcharging if anything-check water level before

charging.

18 volts running is way too much and your XT6 alt. definitely needs a reg.

bajavwsoobnut`s added relay is probably the easiest method of fixing your

starting problem but if you don`t want to go that route do what the

doctor said and measure voltage at solenoid terminal when car refuses to

start

Measuring voltage w/solenoid wire disconnected is of minimal value though

(this will show only complete opens not high resistance-no current flow=

no voltage drop)

Measure available solenoid voltage when car refuses to start by putting

meter + lead on solenoid terminal and - on battery - or starter case/bolt

Should be close to 12 if engine not cranking

You can do this alone by extending your meter leads

If voltage tests low start looking for voltage drops in the control circuit

I don`t have a wiring diagram of your car so I can`t direct you to the

exact locations and wire colors but in general:

When car refuses to start

put voltmeter around various parts of circuit in order

eg. start w/meter + on battery + and meter - on + feed to ign. sw.

turn key and note voltmeter reading,if greater than about 0.1V

then there is high resistance between battery and switch

Continue by checking ign sw contact voltage drop-put meter +

on + feed to sw. and - on sw. solenoid terminal (again about 0.1v

allowable)

Thirdly put meter + on sw. solenoid terminal and - on starter solenoid

terminal- you guessed it,about 0.1v allowable

If any of the drops are excessive you`ve found the bad section of

the circuit.The voltage drops added together should equal voltage

missing from the starter solenoid terminal in the first test

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Guest Cougar4

Tim,

 

You should also check the black fuse link in the box by the battery. This link is what supplies the path for current to most of the items on the dash. I think it also connects the aternators output to the battery. From your symtoms it sounds like you have a bad connection. This is a fairly common problem so look for a burned wire connector or loose connection. If you don't have power to the numerious relays, which this link feeds, you will not get voltage to the starter solenoid to close it when you turn the key along with other things not working. Glen

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Guest chef tim

I went to Advance Auto this morning and had them test the battery. It was bad. Good news is that I bought a three year free replacement battery....COOL!!!! The alternator is still acting the same, so I've pulled it and am going to have it checked/rebuilt. I just don't want to eat up another battery with 18 volts. so far so good, Tim

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Guest chef tim

Had the alt tested, 100amps 14 volts. Put it back on the car, same over charge after 2400rpm. Checked voltage at battery, 18ish, the only thing that didn't check out was the one of the small leads on the "T" connector, but I have to go to work so I don't have time to trace it everything else is good ie fusable links etc. more to come, Tim "the non-electric tool man"

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First the alt. Check voltages on all 3 wires going to alt. Ign on, eng off) Big one should have same voltage as the batt. On the plug with 2 wires, one should read same as the battery voltage. The other wire on the plug will be less. (Should be less) The one on the plug that's at batt voltage does just that, runs to the battery, maybe through a fuse or fuse link, but it should be the same voltage. The second wire in the plug should be less than battery voltage because it runs through the alt/charge idiot light. The light is a slight resistance, thus the reduced voltage. This wire would be dead with the ign switch off. If you have no voltage on this wire with switch on, The bulb in the dash may be burned out. The other 2 wires to alt are always hot. Sometimes, if one of these regulation wires (ones in the plug) don't do what they're supposed to, you get the same results as a bad voltage regulator. (That's built into the alt)

On your first alt, you reved up and it started charging. 18v, is too high. You may have cooked your battery. Charge over night and have tested after it's been off the charger for an hour or three. The alt was putting out, but deffinately non regulated. That is either the wires as mentioned, a bad regulator or both. Sometimes on a good alt and regulator assy, the higher RPM will create enough field current to get it excited and it will begin to charge. (But out of control.) The second alt is not charging at all, that might not be bad either. If it had been setting, there may be no residual magnetism left and the revs may not kick it in. Then we're back to the wires.

Starting. I'm keeping this one short. May be some good suggestions already on the long wire, bad solenoid contacts etc. If you can get any crank with the key switch at all, sounds as if the wiring is in tact. If it cranks up by jumping the soleniod, power's getting to the starter and should be OK. If the battery is cooked, you may only be delivering 6,8, 10, <12 volts to the starter when trying to crank. Drop the volts and the amps go up. Increases in amps can be hard on motors, contacts, wires etc. Also, if cranking volts is low, you would have less volts to suck in the soleniod.

If interested, E-mail me at dalem1@hotmail.com. I could call you or you call me. I'll look at my wire schematics, see if I missed some wiring details, but hope this helps. Nothing wrong with taking bat and alts to have them tested. If all's known good, it won't work right if the wire siganls don't get where their supposed to or the way it's supposed to. (OH, if it doesn't crank at all with the key, a jumper wire into the plug for the park/neutral switch should be enough. I know, the wires are long, but they handled it before, they still should. If volts (batt low) the amps go up and these long neut wire have to work harder.

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Guest kelowna kid

Sounds like you found the problem.Pretty sure both of the T connector wires

should be at charging voltage w/engine running

Backprobe each of them in turn w/voltmeter - lead while + lead is connected

to large Batt. terminal and engine at 2400 rpm

Any significant votage is bad.T connector connections at alt. must be good of course

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I guess I was thinking checking the plug voltages with the plug unplugged. When Hooked up, key on, eng off, the one wire would still read batt voltage. The second wire would almost appear to be a ground wire (-). Turning on the ign switch feeds + to one side of the idiot light. This wire apperaing as a ground at the alt W/O eng running is why the light lights. Once started and charging properly, this wire becomes + and at very near batt voltage, thus, idiot light goes out. (+ on both sides of good idiot light bulb will not light.)

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Guest Bill Putney

Good work, Tim! Now, you know there's likely a connection problem to the alternator (maybe that T-connector, like you said) in addition to the separate starter problem that you can now start getting a better handle on.

 

Now, don't things feel a little less fuzzy and overwhelming (less unknowns in the equation)?

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Guest chef tim

you sound just like that therapist I had to go to when I was a kid...LOL :) And yes your right, I suppose I'll have to work through this electrophobia. Thanks and I'll update tomorrow, Tim

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