UGHHH Truck Won't Start

[coalkickin]

I'm about ready to scrap this truck. Now the truck won't start. When I went to start it...it was making a ratt--tattt-tatt sound...I was having issues with the battery terminals...wouldn't start last week..i jiggled the terminals etc..then it started. Anyway I attached jumper cables on a whim...then I tried to turn it over. It took a few minutes but it turned over. I let it run for a minute or two then turned it off. Went to start it...same sound...I kept trying to start it and the sound trailed off, then did nothing. Lights still worked etc. I hooked the cables back up, started right up. I went for a 10 minute drive, then shut the truck off. I tried to start it up, same sound. It sounds like it is coming from the right front of the engine compartment. I am stumped. It doesn't act like a battery, but when I use jumper cables it starts. Any ideas? Alternator?

 

[fixxxer]

Bad battery cables, they corrode from the inside out. they can look good but be totally cruddy inside the insulation

 

[DeRocha]

The ratt--tattt-tatt sound indicates the starter isn't getting enough power to turn the motor over. This could be from a weak battery, poor cable contact, corroded cables. BTW it takes enormous power to activate the starter 200+amps whereas it only takes 20amps to power your high beams; as such even though the lights work it doesn't mean the battery has enough juice to engage the starter.. How old is the battery and when was it last tested?

If you're working on your vehicle its easy to kill the battery with the dome light left on for several hours..

 

[coalkickin]

Thanks guys...it is probably a combination of the battery and the cables are corroded. I got it started this morning by jiggling the cable..Started right up several times today.

 

[marragtop]

As already stated clean and tighten all cable connections. Also check the connections on the solenoid that is on the right fender/firewall. Just trace the positive battery cable to find the solenoid and make sure all connections on it are tight.