1995 Chevrolet Silverado 350 Starter and alternator problems.! Slow engine cranking, poor charging.

Last week my friend bought a Chevrolet pick up truck from a used car lot. His daily driver had gone kaput, and he needed something fast, yet practical for hauling firewood. As a screaming deal he found a 1995 Z71. The dealer agreed to throw in a used alternator and starter because the engine was turning over extremely slow, and the voltage meter inside the truck was only reading 12.5 volts.

My friend picked me up from my house and took me to the local auto parts store to get some injector cleaner. The first mistake he made that day was shutting off the truck. When we came out to return to his house, the truck refused to start. He could not get the starter to turn fast enough to start the engine. With the alternator barely charging the battery, it was only a matter of minutes before the battery was dead as well.

With the used replacement starter in the truck, we went inside and bought a $3 wrench set. SAE. The starter has two 9/16" bolts that hold it in. A 1/2" nut holding the starter power wire in place, and a 5/16" nut holding the solenoid actuator wire in place. I removed the batteries positive connection to avoid shorting out the battery during removal of the starter.

After lowering the starter I was able to reach both the main power wire and the solenoid actuator wire. After removing that , the installation was the exact opposite of removal. The final step was re attaching the batteries positive, but the positive bolt was stripped. Inside the auto parts store they had the replacement stud for about $3 more dollars. I asked my friend if the battery ground was any good.

My literal question was "Does the ground only go to the body? Is there an engine ground?"

My friend replied by stating " There is a ground wire going to the fender, and a larger wire headed down under the engine"

It was then that we moved back to the starter for a culprit.

Having the second used starter in place, we turned the engine over and it turned even slower. Instead of getting a jump start, my friend bought a 800 cold cranking amp battery, to replace the starving 750 cold cranking amp battery. Low and behold, there was no change. The truck turned over even slower yet.

Then we took the original starter in the store to have the part numbers cross referenced. The starter was correct. We had the sales representative attach the starter to their bench tester. The starter had a good current draw, right smack dab in the middle of the needed values.

Now we are convinced that the starter , most likely needed shims, as Chevrolet was notorious for using shims. We bought a $3 Shim kit and placed the shims in .040 first allowing the truck to start.

When the truck started, we headed back to his house, where I continually lowered and raised the starter again, until placing .100 inches of shims under the starter. This did pull the starter away enough to get the engine to start. To aid in the starting of the vehicle, we retarded the ignition timing. This relieved the combustion pressure against the starter allowing for an easier spin of the fly wheel.

Then we moved on to changing the faulty alternator. A very simple 15 minute task. The used alternator seemed to put out less voltage than the original leaving us no option then to put the original back on.

The next day my friend was hot and bothered. Nothing that was logical seemed to fix the problem. So he took the truck back to the car lot. The lot attendant offered to take a quick look at the truck, and decided to put a jump box on the battery. Maybe there is just not enough power to start the truck.

Initially the jump box had no effect. The lot attendant had hooked the box directly to the battery. Then for some strange reason, the two of them decided to remove the battery from the circuit, using only the jump box to start the truck. This too had no effect. Then, low and behold, it came to my friend; We were always taught not to attach directly , battery to battery; So he instructed the lot attendant to power the red with the box, and land the black on the alternator mounting bracket.

BOOM! The truck breathed instant fire. The ground strap from the transmission bell housing to the firewall was not there. We need to remember that the engine mounts are rubber and do not allow for a good contact to ground. Painted transmissions, engine blocks and accessories all hinder a good ground path.

Then he looks again. Tracing the large black wire from the battery, to the attachment bolt. The large ground went to the frame, not the engine block. He moved the large ground to the power steering bracket, and added a frame ground. The starter is working like new, and the alternator is able to put out a full charge.

It seems that the engine was changed, and the ground was never placed back on. The starter had a parts house sticker, as did the alternator. Both of these parts were replaced as well. The person who changed the engine must have gotten paranoid about crank bearings and traded that truck in. The truck is in excellent condition with low miles. Poor installation left somebody believing it was a bad buy.