Mechanical Question......

Yeah me too, for sure the pre cup 3408 had to be the last, but I'm not sure they used them in trucks. All the v-8 I seen were direct injected. Course they were mostly gone by time I came of age

 

465 check the fusible link on the firewall. Love computers, they have no job controlling a truck engine. I'm old school.

 

I had it on my old '69 Freightliner, NTC 335 Cummins and had a decompressor as well. A kid could walk by with an ice cream cone and that thing wouldn't start.

 

OK let's start with a couple questions - what do you mean when you said "push the start button and everything seems to go low"?

Do you mean that the volt meter goes down, or do you mean that it sort of cranks but doesn't want to?

Do you have someone looking at the headlights when you push the starter button on?

From what I can figure out, one of two problems are possible, the first one is that you don't have the starter hooked up right or the wire from the starter button is on the wrong terminal (another possible problem could be that there is a missing jumper on the solenoid).

The other problem is that the positive cable is bad to begin with and needs to be replaced.

 

Ummmm nope got em a much newer THERMO KING!!
Just Sayin

 

Our Straight trucks still have them.

 

i forgot the 1st 3406s were precup engines, i think they were 365 horse. if i remember rite some were converted to direct injection and rated at 375 horse.

 

A loose battery cable or corrosion on the batteries is probably the simplest fix that would cause this.