78 cj7 quit and won't start
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78 cj7 quit and won't start
- Thread starter 96in85
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BusaDave9
Always Off-Roading Jeeper
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- 1979 Jeep CJ5 with 304 V8, T18 Transmission, Dana 20 Transfer case with TeraLow 3:1 gears, 4.88 axle gears, Detroit Locker up front and Ox Locker in back with 1 piece axle shafts, 36" SuperSwamper SX Tires, Shackle reversal, MileMarker Hydraulic winch, MSD 6A ignition.
Yes, the rotor in the distributor should turn as the engine turns. It turns because a gear on the cam turns the distributor shaft. If the cam isn't turning (check valves) then it's the timing chain.
If the vales work then it could be the gear on the bottom of the distributor shaft. Is the distributor OEM? This is a common problem with cheap HEI distributors.
If the vales work then it could be the gear on the bottom of the distributor shaft. Is the distributor OEM? This is a common problem with cheap HEI distributors.
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You need to pull it and check it.
MarkCJ7UK
Jeeper
If you can turn the rotor freely by hand and the rotor is located correctly on the shaft it is a fair bet the shaft or gear on the shaft of the distributer is faulty , , If you turn the engine over by hand by turning the crankshaft pulley and the rotor does not move it is a fair bet it could be the timimg chain broken and not turning cam shaft ,,
DO NOT USE THE STARTER MOTOR TO CRANK THE ENGINE , IF THE CHAIN IS BROKEN A PISTON MAY HIT A VALVE IF THE CAMSHAFT IS IN A POSITION COMPRESSING A VALVE .. THE PISTON WILL LIFT AND HIT THE VALVE AT THE TOP OF THE STROKE
DO NOT USE THE STARTER MOTOR TO CRANK THE ENGINE , IF THE CHAIN IS BROKEN A PISTON MAY HIT A VALVE IF THE CAMSHAFT IS IN A POSITION COMPRESSING A VALVE .. THE PISTON WILL LIFT AND HIT THE VALVE AT THE TOP OF THE STROKE
jdcaples
Old Time Jeeper
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Dana 300, SR-4, stock and rusting; I'm the fourth owner.
I had the same symptoms. A PO installed an HEI distributor with a brass gear. I sheered that soft metal when I was doing a tune up and adjusting the carb. I think a backfire did it. Now I have a steel (or some metal containing iron) in its place.
-Jon
-Jon
hdgapeach
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- Right now, only one '76 CJ5. 304 with a three speed stick. Everything else is pretty much stock 'cept for a 4" suspension lift. Came to me with a back breakin' 4" suspension lift attached to a reverse shackle setup (Reversed the reverse shackle :dung: and now she rides like a Caddy!) Also posess a few 60s & 70s Mustangs and a couple of late 70's F150s 4X4s.
Guess the 4.7 ain't a zero clearance engine then. Whew......
Push the button. I dare ya!