My 1984 Chevy 1/2 ton 4x4 will not start after the engine gets hot. It is a
5.7 liter. The starter will not crank the engine. I have replaced the starter (twice), alternator and battery to no avail. Can someone help me solve this problem?
First thing to do is check the timing. Too far advanced will make a hot engine not start. Check the initial, running & if all else fails the cam (ie make sure your timing marks on cam and crank line up with not chain slop). Charles
Ignition timing has nothing to do with how fast or slow a starter cranks when the engine is hot or cold. Your problem is likely caused by bad battery cables/connections, especially the main ground. Check all cables for corrosion and clean all contact points.
As temp increases so does resistance, so what's happening is your marginal connections are fine when cold, but don't flow enough juice when hot and the resistance is higher.
I just wanted you to know I had a 72 nova that i put headers on and it cranked slow i thought the starter was over heating,reset the timing and it started fine. Bobby
Retarding timing for easier HOT starts is a OLD Demolition Derby trick. Basically when a Engine is past XXX degrees it spins over slower then it does at ambient.
A heat soaked, weak, or dying starter compounds this problem. As does a weak battery.
Now when it comes to Old SBC's over the years timing chains can streach, heads can crack, starters lose there "ass"( or some jason puts a low torque in place of a high torque). If the timing is advanced for say 92 or 93 Octane, and the truck is running on 87 Octane, with worn parts, Retarding the timing some will help it start better.
I'm not saying it doesn't work, I'm just saying it's band-aiding a problem caused by something completely different. The ECM assumes base timing is set correctly and advances from there in closed-loop, so if the base has been bumped down a few degrees it's going to be running less advance once started, causing decreased performance and fuel economy.
All he needs to do is clean/replace the battery cables and connections and he'll be good to go, with the timing set correctly.
It's a 1984 1/2 ton. That means CCC & CST Distributor. The engines still can having timing advanced or retarded for fuel grades. The CCC (Computer Controlled Carburator) is known for having Choke issues.
Those engines use vaccume & Computer controlls that basically fight each other. A bad vaccume line, or someones attempt at circumventing the emmissions controlls can make them run like total crap. Charles
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