'88 C1500 - 350 TBI Crank, no start

gmthaze

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I got a '88 C1500 last year from my father in law. The first few months it drove fine (not a daily driver) but then decided to stop starting so I went looking and found a corroded battery cable and replaced it. It worked fine after this but during the winter, I didn't drive it much.

I tried to crank it last week and no start. I found the side terminal bolt was stripped and was loose, so I replaced it and tightened it right up, gave the battery a jump and let it ran. Truck started and drove for about 15 minutes no issue, I went out about an hour later and started back up. I tried to start it last night but again didn't start. It was late so I didn't diagnose more but looking for some help.

I am not very skilled with cars so not sure what to check. I think I have a bad ground since the radio whines. There is nothing on to kill the battery either.

TIA
 

Trig

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Could be a few things - most tend to recommend:

Make sure battery is good/fully charged. Any auto parts stores will do this for free if you take it into them.

Cleaning up all the electrical connections - take them apart, wire brush (die grinder if you have one) to bare metal, apply dielectric and re-fasten. Grounds, starter connections etc. I recently did this to my 97 and they were all noticeably corroded with the white powder looking stuff at a minimum.

After that you're going to need a multimeter to follow the voltage through the system to see what's not allowing the circuit to close to allow the starter to do it's thing. Start by making sure 12 V is present at the main connection to the starter solenoid (B, Always Hot), and when you crank 12 V should be at the smaller S terminal, which if present should crank the engine. Obviously if voltage is not present at those locations start backtracking the wires through the system until you do read the 12 volts identifying where the problem is.

It can get more involved as bad cables can cause resistance where the above may check out as far as voltage but that's not the whole story. Voltage present shows the pipe is open so to speak, but current is the amount of juice that can flow down that pipe. The pipe may be open but may not pass the current needed due to corrosion or some other defect. You can measure resistance with the meter from say the battery posts to any other point and see how many ohms you get, should be 4-6 I'd say. More than that you'll need to clean connections and/or replace.

If that checks out then you'll need to check readings while cranking the engine with a helper. If the above points read the voltage correctly while not cranking check voltage drop while cranking across the battery positive to solenoid always hot, negative battery to solenoid case/starter case, as well as any grounding points/straps to negative battery post. If while cranking you see more than a 0.5V difference you likely have a bad cable/connection etc.

If voltage drop is not a problem then likely your solenoid/starter is bad. You can bench test off of the truck, or an auto store can test it for you as well.

There's a bunch of youtube videos going over this process under "no crank" or similar. I'm not an expert by any means, so definitely review something else before diving in if this isn't something you're used to doing.

Good luck - as long as you take your time you'll be able to figure it out.

Chad
 

Schurkey

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I have the impression that this is not a case of "cranks but won't start"; it's a case of "won't crank". The diagnostics are entirely different between the two.

NOTE: When folks talk about "12 volts", what they really mean is "system voltage", which had better be pretty close to 12.6--12.7 volts when the engine is not running, and 14+ volts with the engine running and alternator charging.

If this really is a case of "won't crank":

FIRST, assure that the battery is fully-charged. A voltmeter should show 12.6--12.7 volts when connected across battery positive and negative terminals. If not, connect a battery charger. When the charger is first disconnected, the battery voltage may be above 12.7 volts--even above 13 volts--until the surface-charge has dissipated. That could take a couple of hours, or you could turn on the high-beam headlights for twenty seconds or so. With the surface-charge gone, you should have 12.6--12.7 volts. For the record, a slow charge for a long time (overnight) is recommended. Fast-charging is not a great idea most of the time.

Next, assure that the battery terminals are shiny silver color; and there's no corrosion on the cable ends. Lead or steel cable ends should be shiny silver colored. Brass cable ends should be bright brass colored. No matter what the cable ends are made of, delicate fuzzy green, or smooth, hard black, is no good.

Battery fully charged? Cable ends cleaned and tight? Try to start vehicle. If it starts, fine. Check charging voltage, which should be 14+. (If you don't have proper charging voltage, there's about a half-dozen possibilities.) And check battery voltage again tomorrow. And the day after that. And if the starting problems have gone away...you're done.

If the battery voltage is low after a day or two, or the vehicle still won't crank with good voltage and clean cable ends, you're gonna have to dig deeper. Since you're "not skilled with cars", that probably means taking it to a shop. As said...you can take the battery, alternator, and starter off the car and haul them to a parts-store for "free" testing, but there's two problems with that:

1. The pimply-faced kid behind the counter may not perform the test properly. He may not TRULY know how to connect the part(s) to The Machine that performs the tests. Or he may sabotage the test to sell a new part. Good parts are condemned negligently or intentionally, the parts store makes a sale, and the car doesn't get fixed because the wrong thing was replaced.

2. Even if the battery, alternator, and starter really do check out "ok", they're not testing the wire harness that connects 'em. Lots of problems hide in wires and wire connections.
 

Erik the Awful

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I found the side terminal bolt was stripped and was loose
If you have to make any kind of battery cable repair, I highly recommend making the switch to a top-post battery. Some people swear by side posts, but a couple times a week someone says that their side post came loose. The rate of failure for top posts is an order of magnitude less.
 

Frank Enstein

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Alternators are horrible battery chargers but they are GREAT battery maintainers!

Get a battery charger. It doesn't need to be expensive, it just needs to be automatic. Meaning it will turn itself off or go to a maintenance mode.

I just bought this one for myself;


but one like this will work.


It will just take longer to charge and it won't have all the extra features the top end one does.

Both of those are the newer technology chargers that are smaller, lighter, and will charge the battery faster than the old ones.

Charge the battery overnight and then do the tests.
 
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