350 engine just cut out on my truck

hey, my 93 silverado just died out today on the highway with no sign. It is a stock motor 5.7. I was driving down the highway and out of nowhere there was a smal jerk/thud and it was off. wont restart. I dumped some gas into the throttlebody while turning it over, not a hint of starting.so I checked the spark and it didnt appear to have any. I went and put a new coil on it and still nothing. It doesnt sound like anything gave out internally. Coolant was low, but It was cool enough when I pulled over to pull the cap. Still has oil. completely lost. Im having it towed home now so I can check it further. Any ideas out there?

when I first pulled over it chugged a couple times like it was going to but never did. after a few attempt, just turned over.


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does the distrib rotor turn with the engine ? im thinking possible timing chain failure, although rare. see if you can grab the crank pulley and see if you can feel lots of slop in it back and forth, or if the crank gets stuck trying to turn it one way

Is the rotor turning?

If so, check for set codes, check all the fuses- including the ECM and fuel pump.

If nothing there, you might check the ignition module and pick-up.

yes, its does sound like a timing chain failure. the same thing happened to my dads 87 mighty max (haha i love that thing) at first i had thought the thing got hot and ceased up on me, but just a timing chain failure.

If it has the separate coil and HEI small cap distributor set up, chances are higher that the sensor inside the distributor or a wiring connection failed.

For a coil in cap HEI, it's probably 50/50 that the coil or the pick-up sensor died.

I'd say that if it won't fire a prime the fuel pump is probably fine, but that was my first assumption till you got to the part of priming and no start and checking for a spark that isn't there.

Bogie

thanks. I did notice that the chain isnt broken, but It appears to have slipped. The rotor does still turn though when cranking the motor. When I set the dist at #1 cyl, the the tdc notch on the ballancer is like 1/3 rotation away from the timing tab. But it doesnt have spark either. I just replaced the module waiting for someone to help test it. I took a plug wire of and put a fresh plug in it to see if it`ll spark. I cant see why that wouldnt work. Isnt it weird that went out the same time the chain slipped?

I'm not sure how far that distance is (1/3), but if your timing chain jumped a few teeth, you may have bent some valves as well.

damn yea, I didnt even think of that Hope not. 1/3= ~120 degrees. Its prob actually about 100 degrees off. well, If I did thats an excuse to get new valves, springs, seals, lifters and a good cam I guess to be optimistic about it. might be better off just getting some new (used) heads in good shape with new lifters and a cam with chain set. I suppose a leakdown should figure that out?

that, or you could check out some of the valve stems for any valves that may be stuck, the latter being the 'easiest', I guess. Anyways, sounds like a tear down, if the balancer is really 1/3 off. I initially thought electrical, but the balancer being off doesn't sound too promising.

it was electrical. I changed the module and put it together and have spark. Next Ill check the valves. Thanks for all the help, Ill post the turnout.

Are you sure it is up on 1 and not 6. That would be 180 out.
It is probably loaded up from all the cranking, try holding it to the floor while cranking. This accomplishs 2 things, lets more air into to engine and shuts the fuel off so you wont flood it more.

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