i have a 75 k5 blazer rock crawler, it has sit for 5-6 yrs but last summer i took it out ones and broke a brake line so this week i started working on getting it going again and been trying to get rid of all the rust and am getting brakes soon but has been funny it wont allways turn over i have to try i copple of times, yester day after i and moved it i went to go start it again to move it and it would not start it dose nothing eny help on where to start trying to fix this broblem??? thanks

 

All battery connections (at the battery and the other end of the cable) clean & tight?

Have you tested for power at the starter on the large wire as well as the smaller wire while cranking? Compared the voltage at the starter during cranking attempts with the voltage at the battery while cranking?

 

all connection at both ends are clean and tight dont have a way to compair the volages (most of my tools are at my dads towing yard locked up from when we moved out of are shop) i have power to every thing but when i turn my key evrything stops working but the brake light stays on idk much about wireing but i think its in my stiring wheel or a fuse or somthing but i dont know what to do first

 

It is possible that your ignition switch isn't adjusted properly. The ignition switch is on top of the column near where the column meets the dash. The ignition cylinder, when turned with the key in it, moves a rod which moves the ignition switch.

Beyond that, you are going to have to get a multimeter and start testing for voltage where you know it should be.

 

thanks ill look at that if that dont work ill wait untill my dad gets home and see if he knows his truck as well as i think he dose.

 

You may have a corroded connector internal to the starter solenoid. Remove the negative terminal from the battery and then remove the starter. You can then easily remove the solenoid from the starter and carefully disassemble it. The LARGE bolt used for the + battery cable can be removed...rotate it 180 degrees and reinstall it. Put everything back together, reconnect the negative battery terminal and that should cure any cranking problems.
This presumes that the battery has a good charge and as swartlkk says, check your ignition switch.
Best of luck!

 

bang on the starter and see if she cranks after / also check your crank fuse in the fuse box GL