new alternator now won't start.

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Mattstaff

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HEY YALL, I need some help. I recently purchased a 1984 K10 with a 305 automatic trans. I've only ever owned or worked on 2000's and Newer trucks so all this is new to me. The truck ran pretty decent when I got it but didn't have a alternator belt so it was just running off a new battery the previous own had out in. today I decided to throw a belt on it and started it up and the belt and alternator had a pretty bad squick or screech coming from it but everything was running alright so I cleaned up and let it sit and run for awhile. (Its currently 15 degrees out in Minnesota so I wanted to let it warm up). I went inside for a-little bit and when I came back out side the truck was dead and the battery was dead to so I figured that the alternator was shot and a threw in a new one from the store and charge the battery. And now the truck turns over all day long but won't fire even with starting fluid. I don't even know where to start on something like this so im looking for all the help I can get.
 

SirRobyn0

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HEY YALL, I need some help. I recently purchased a 1984 K10 with a 305 automatic trans. I've only ever owned or worked on 2000's and Newer trucks so all this is new to me. The truck ran pretty decent when I got it but didn't have a alternator belt so it was just running off a new battery the previous own had out in. today I decided to throw a belt on it and started it up and the belt and alternator had a pretty bad squick or screech coming from it but everything was running alright so I cleaned up and let it sit and run for awhile. (Its currently 15 degrees out in Minnesota so I wanted to let it warm up). I went inside for a-little bit and when I came back out side the truck was dead and the battery was dead to so I figured that the alternator was shot and a threw in a new one from the store and charge the battery. And now the truck turns over all day long but won't fire even with starting fluid. I don't even know where to start on something like this so im looking for all the help I can get.
Well the principles of the combustion engine on newer rigs are the same as the older ones, if you think of it like that maybe it won't seem so strange. So what does an engine need to run, fuel, spark and air right? If it won't fire on ether then it's got fuel, unless it's severely flooded fuel is not the issue, and it's got air, so it must be a spark issue right?

I assume you know how to check for spark right? Easiest way is a spark tester, but if you don't have one just pull a plug wire off a spark plug, put a spare spark plug in the end of it and ground it out. Preferably have a partner crank it over, or get it grounded out somewhere you can see it while your cranking it.

If you confirm no spark make sure the + wire is plugged into the ignition cap, assuming it is, pull the cap off the distributor and see what kind of shape the cap and rotor is in. If that all looks good most likely the coil or ignition module is bad and there is not a really good way for you to test them, so probably best to replace them both as they are likely 40 years old.

Hopefully this helps.
 

Rusty Nail

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Wow old thread, I wanna play!

Bought it with a bad alternator that had no belt...rather than all that crap you were talkin about , I bet the alternator siezed up and threw the belt.
I bet half my total that the alternator ground wire was severed at that bracket.
He could have lost the fender ground OR the constant hot to distributor fusible link on the firewall but whatever.

Any of those seem like a better place to start looking than under the distributor cap but whatever.
Not a spark issue.
Voltage path.

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82sbshortbed

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Maybe this?
 

Ontheboulder

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check your fuses,when the alternator died it may have taken a fuse with it!
 

Ricko1966

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I'm thinking when he went to get the alternator @mtnmankev s aliens stole his camshaft for their space ship.
 

mtnmankev

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Let's leave my space aliens out of this for the time being, they have been rather well behaved lately, at least around here.
IF the OP is still around, I suggest major troubleshooting and testing of all things electrical on his truck.
And @RustyNail I will beg to differ on the Castrol ... I have been running GTX for MANY years and have never had an issue from the quality of oil.
 

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