I replaced the starter and alternator. Both old. No changes in the wiring that has been on car for some time. After installing and running all seemed fine. However after a couple days. Battery was low. Charged battery . This AM went to start and battery was low again. I decided to try and jump start and after one engagement of key switch the motor turned over ( I did not try to go with a full engine start) when I released starter switch the starter continued to run.
Removed jumpers , starter stopped. Removed starter checked for bare wire on S and R wires. Added another heat wrap on S wire. Checked starter motor with switch engagement not full installed. Appears as though I have control with sw in this configuration.
However after fully installing the starter, Same result. Starter does not engage with initial power application … only after engaging the ignition sw for first time ..then the starter runs continuously and I have to remove power to stop the starter.
Confused.

 

Lets assume the car you are asking about is the 71-72 in your avitar picture with a 350 & TH350 trans????

Do you have a good VOM....volt ohm meter?
You didn't have this problem prior to the installation of the new parts...right? I hope you kept the old parts?
My guess is you have a faulty new starter. Sounds like the solenoid is bad or the starter drive fork is hanging up.

We consistently and repeatedly advise people to consider rebuilding OEM components (such as starters, alternators, and water pumps) rather than exchanging them for new aftermarket offshore junk alternatives.
Our experience indicates that remanufactured OEM parts, which are restored to original factory specifications, offer superior reliability, durability, and a precise fit compared to many new, lower-quality (china junk) aftermarket units.

Check for current draw at the battery. Then disconnect all wires at the starter and check again for a draw. No draw problem located.
Same drill for the alternator. Does the alternator housing feel warm when the engines cold? Do you have a voltage regulator on the firewall?

Measure the running voltage at the battery and report back on all of this.

 

You may have the S and R terminal wires swapped.

 

The original problem was car would barely turn over. I had not driven it for awhile. Finally got it running with charging and jump start decided to drive around and let battery charge up. Car died after about 15 minutes when I gave it almost full power. Could not get it started again and had to tow home.
72 350/350 Cutlass

Replaced starter and Alt.
Did not keep old units
Voltage Reg on firewall.
Interestingly I think the alt may have felt warm with engine cold. Although it was spinning when engine was during my start attempts.
Think I need to charge battery back up before doing tests. Batt was down to about 8 volts without jumpers

 

Stop throwing parts at it!

Before doing anything else, unhook the battery, put it on a trickle charger for at least 24 hours. Have the battery load tested. If the battery is junk, then obviously the starter will turn slow.

Reinstall the battery. If it still cranks slow, use a voltmeter to check for voltage drop. Put the POSITIVE probe of the meter on the POSITIVE post of the battery. Put the NEGATIVE probe on the meter on the POSITIVE stud of the starter. Crank the engine and read the meter while cranking. Ideally, you want a couple tenths of a volt. If it’s more, you have defective or corroded cables or a bad connection somewhere. You can check the negative cable using basically the same process. If the cables are bad, don’t cheap out on them. Get cables at least as big as the originals. Unfortunately, like everything else, cables are made cheap. Since insulation is cheaper than the copper, the cable might be the same physical size, but the copper inside is smaller.

If you still have problems, then I’d suspect the starter. It sucks that you have to go thru these added diagnostic steps, but the quality of replacement parts is questionable.

 

Your battery is 100% useless - completely dead @ 8VDC. Measure running voltage at the battery with the car running, also. ALT should be able to supply ~14.0VDC to battery.

 

EDIT: Never mind, I found it in Post #4.

We should not have to assume what car, manufacturer, model & year you are referring to. Please state manufacturer, year & model.

 

Norm, Matt, Eric. This is the prob trouble shooting in cyberspace. Good call....basics...battery condition and correct solenoid connections.
Redbud40...
Step 1, solenoid connected correctly.
Step 2, battery good or bad? Load test it.
Step 3, measure running voltage.
Do all of this, report back then we'll continue to help with more basics.

Any chance of buying back those old parts from the parts store before they ship them out for "rebuild". I'd inquire.

 

Thanks for the checklist of required items. Diagnostics has never been my strong suit.
Got the battery on a good charger awaiting the full time allotment till running further checks.
In the mean time verified that the purple wire from start switch is in fact going to the S side of the solenoid.

Also in looking at the wire diagram ,tapping the starter solenoid 12 volts directly to the horn relay is what the diagram calls for.
Allot of on line pictures appear that people have moved this wire directly to the actual battery or somewhere else for 12 volts.
What was the thinking of the original design vs just going off the actual battery?

unfortunately the components I took off are gone ….. lesson learned.

 

Sounds like a bad battery to me. Low volts will cause high amps at the solenoid contact causing it to arc and stick together. Could also be the drive is moving to far forward due to a broken or loose retainer ring on the armature shaft. Or possibly both.

 

Turns out the main culprit was most likely the battery charger I was using. It was unexpectedly going into recondition mode and actually not really doing anything. Also the 8 volt reading was from the charger. When charger was saying complete nothing was actually charged ..Finally got a descent charger and volt meter on there and started getting accurate info.
After a night of charging on the new charger 12. 6 Start it drops to 10 and running 14 .6.
Lots of great lessons learned especially the arcing of the solenoid with a low state of charge on battery.
Now on to wiring mess of the AC that I don’t really use but need to clean up the loose wires dangling around!