1. Welcome to PlowSite. Notice a fresh look and new features? It’s now easier to share photos and videos, find popular topics fast, and enjoy expanded user profiles. If you have any questions, click HELP at the top or bottom of any page, or send an email to help@plowsite.com. We welcome your feedback.

    Dismiss Notice

Relay or what?

Discussion in 'Chevy Trucks' started by mike bisbano, Jan 24, 2002.

  1. mike bisbano

    mike bisbano Junior Member
    Messages: 7

    :confused: I overheated the 400 small block in my 85 k20 the other day while plowing, stalled it, then thought I'd fried the sterter, attempting to restart. So I put a new starter in today, but no dice. It won't spin, won't even click. Battery is brandy new, so is the alternator. The starter is definately hooked up correctly, and there is plenty of juice going to the starter too. (I did the screwdriver to the terminals trick, it spun the starter, but the solenoid didn't kick in). What's up? Is it the ignition switch, or os there a relay somewhere? I looked at Chucks schematic, and it shows a block on the firewall, does that have a relay? The horn blows, the lights light, key won't start the truck!! Any ideas?
  2. 75

    75 PlowSite.com Addict
    Messages: 1,382

    Mike, one quick idea comes to mind: follow the wires from the starter up toward the cab and that terminal block you mentioned. Look for a fusible link in the wire, it will look like a small cylinder (about the same diameter but a bit shorter than a AAA battery) and see if it or the adjoining wire insulation looks charred, blistered etc. If it does, the link may need to be replaced, try running a temporary wire and bypassing it to see if that takes care of the problem. If it does, you'll need to replace the fusible link which is a matter of cutting it out and splicing a new one into the wire.
  3. John DiMartino

    John DiMartino PlowSite.com Veteran
    Messages: 2,154

    No relay,just a soleniod on the starter motor,you should be able to jump the battery lug,to the small lug that's your start wire,this should engage the starter motor,if it engages,and still doesnt spin over,you may have seized the engine,if it spins,you need to check the neutral safety switch,or clutch switch,if its a stick.You may have a broken wire ,or bad ignition switch too.If if its really driving you nuts,maybe you have a freind who can help,and who knows more than you.I decent mechanic could get it running,and diagnosed in under 10 minutes,so long as it isnt seized up.400 SB's are great engines,but they do not take to overheating very good,so if it got real hot,its likely toasted.