Thread: Help! 350 small block got hot and turned off now wont start!

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Just a thought, back in the late 60's thru 70's GM was using a nylon encased timing chain sprocket on the cam to quite the noise. They seldom lasted past 60,000 miles, when they went out it was usually as the motor rpm came down (most of the time at shut off). We used to check for wear with a timing light, if the timing wasn't steady (jumped around) at a set rpm, it usually indicated the timing gear had excessive wear. Once they jumped they would not start, we used to hold a dollar bill above the carburetor while someone cranked it, if the bill blew up away from the carb it was the timing chain.
Saw a lot of these fail, and we got real good at changing timing chain sets..

You can get a good idea if that timing chain has issues by rocking the engine back and forth while watching the rotor button. Easier by far with plugs removed.

If you can rock the engine back and forth and the rotor doesn't move, It's got a lot of slack.

Will check tomarrow. Rpm gauge isnt registering at all. Even disconnected it but still no start. This sucks

I typed out a pretty well complete system to follow along with numerous issues I saw in his pics but the site mal functioned as I clicked reply---------
In a more abbreviated form------move the fuel line out of between the water pump and front of block, while hoses are disconnected, pump fuel into a 2 liter pop bottle to check for debries in fuel, amount of fuel ( if any) and also this (fuel pump action) will tell you if timing chain is still working(altho it may have jumped some teeth)---fix the ground wires and battery cables, take Teflon tape off carb fittings (never use Teflon tape on fuel or brake systems) Sepentine belt drive systems commonly use reverse flow water pumps, your system however needs normal rotation----
Before buying a bunch of parts-remove plugs, dist cap, compression check, while plugs are out hook up remote starter switch to solenoid, jump hot wire to dist, check for spark (plugs hooked to wires laying on metal surface) do the fuel line stuff I mentioned, turn crank with socket til #1 is coming up on compression stroke, check timing mark as piston comes to top dead center, check rotation of distributor rotor (all this will also tell status of timing chain)If good clean fuel, compression and spark while directly hotwired, you may just have issue with ignition switch in any of the 3 positions-accessory (powers fans) ign on ( distributor power) start ( accessory/ignition bypass-dist powered from starter solenoid

Will try all this. Pretty sure fuel is clean cause i have a sight type fuel filter before fuel goes into carb and fuel in there is real clean but will check timing chain first thing tomarrow morning and compression.

Hang in there and follow the above advice. It will help us narrow down the possibilities. These types of problems can and will drive you crazy, but they are almost always simple in the end.

OK so I took off cap and tried to start car rotor moves. I also put a socket on crank and with every little movement the rotor moves. I tried again to get spark for the 3rd time on the plugs with 3 different wires and again no sparks at all where the 1st test for spark also gave me no spark but the 2nd test gave me very little spark. I mean it was so weak it was barely even visible. I pulled off the coil in the cap and it does have rust stains on it in certain areas. Still no luck with the rpm gauge working. Stays on zero when trying to start the car. All other gauges are working properly. Checked fuel and its clean and it gets to the engine. . Won't really be able to replace the coil and module till at least a week n a half from now cause bills always do come first and Mallory parts aren't exactly cheap but first chance I get I'm changing them

Why are you so bent on throwing parts at it instead of qualifying exactly what you have and don't have???? You need to do some isolation of the ignition system from all the dash and tach stuff----------Hotwire jumper wire direct to ignition
Remote starter switch to turn engine
does fuel actually spray from accelerator pump nozzles
have you checked float levels
are you getting compression (check with finger in plug hole while you turn crank to # 1 cylinder and does the compression change to suction as the timing mark goes past tdc?
turn engine until rotor is pointed exactly at a cap terminal and hook a wire to that cap terminal and hold on to the end of wire while turning the ignition on and off several times----will be very slight tingle so don't worry-best to touch finger of that hand to intake manifold and only get tingle thru finger---

I wanted to add, with the plugs out - spin the motor by hand until the timing mark is at zero on the timing tab, now, slowly turn the motor in the OPPOSITE DIRECTION and make note of how many degrees you can turn the crank BEFORE the rotor turns.

6 to 8 degrees acceptable play in the timing chain, 10, 12 or more is un-acceptable. This information along with a compression test will give a good indication of the motors health inside.