I have a mild build sbc motor in my 54. It has a mild cam headers edelbrock intake and a holley double pumper carb. around 400 hp. I didn't build the motor, and the car is new for me so I haven't had the time to get into figuring out every component yet. last weekend I was driving down the road and the car gave a small back fire and shut down. I went to fire her up and after I tryed to crank her over a few times the starter began to bog down. then the starter would not turn her over. I have a new battery and she is charging. The starter almost sounds like the timing is advanced to much to me. I am on the side of the road and I am thinking it's an ignition problem, may be an electrical problem and the guy who sold me the car says it did the same thing to him. the gas gage is not calibrated correctly. What he did is put some gas into her and she fired right up. Sure enough as soon as I primed the carb the starter began to turn over the motor. After cranking her over a few times she starts to pick up gas and fires up. Could any one explain to me what gas has to do with the starter being able to turn over the motor? I never owned a car with a hotter cam than stock. I'am thinking thats where i am getting confused. thanks tom
maybe the starter was just hot from cranking..and by the time you got some fuel back in the tank , the starter had a chance to cool back down.. its not a good thing to do to your starter or battery to crank and crank and crank an engine..if it dont fire off in 3 trys..somethin aint right and cranking it to the point of running your battery dead isnt going to fix it. nice lookin 54
lack of gas has nothing to do with whether the car cranks or not. adding gas did not cause the starter to start working again.
i did not crank the motor very much. I am some what of a back yard mechanic. I have rebuild a few motors. i have a clue of what i'am doing. i have started many motors and never had this kinda problem. i probally cranked her 5 or 6 times for a total duration of 5 seconds each time. then the starter would not turn the motor over more than 1 revolution. i tried to start her just before i primed her and she would just about turn over. than as soon as i added gas it turned over. it got stronger as i turned the key to crank the motor until it picked up enough gas to fire. i was under the impression that the fuel and the starting system were totally independant. it makes no sense to me. also she has no choke set up. you have go under the hood and adjust the choke several times to start her. its a pain. the reason i mention this is i crank her over more than i did on the side of the road just to get her running when i first fire her up and have not had this kinda problem in the past. this is my first motor with a hotter than stock cam and a double pumper. it sounded like the compression was bogging her down or the timing was advanced to much. but when she got some gas it started right up. am i just connecting the two events together with out any merit? I was told the motor produces around 400 hp. i never dynoed her but a crate motor, mild cam, edelbrock intake, headers, 3 " exhaust, double pumper carb. not sure of the heads. sounds like the set up could produce 400 hp. is their any way the absence of gas would cause the motor to bog down? could the timing be advanced to much but the addition of gas cause the motor turn over easier? i'am shooting for any explanation. or am i tripping. tom
Blown head gasket maybe? Water in the cylinders would make it hard to turn over, extra fuel gives it enough urge to spin? Try whipping the plugs out and see how it turns over and if there's any water spray for the plug holes.
The starter has a thermal circuit breaker, like a real electric motor has. Or there is a broken field wire connection that is doing the same thing as a breaker. I got a starter on a SBC that does the same thing. but everytime I think I should take it off and take it apart, it starts fine. BTW, nice car there. Take of the front plate, NJ says you don't need it with the QQ's. Frank
Only thing i can think of is might have something to do with high compression. The starter has a hard time turning over the engine but when theres fuel added, even alittle, its enough to spark off the fuel to push down the piston and make the engine turn over easier. Im just guessing.
thanks for the replies. i'll check the plugs. but i would think water in the cylinders would show white smoke at some point. your point about when the car gets gas it might be enough to overcome the water in the cylinder is the same thought i had. but instead of water i was thinking the timing or compression was the culprit. i am also liking the bad wire or weak starter theory. i was going to check the starter any way. when cranking the motor it makes a loud screech. Almost like it isn't shimmed correctly. i'll go over that when i get a chance. funny thing is the shop who installed the new motor specializes in auto electric. thanks for confirming my thoughts about fuel and starting systems not effecting each other. i thought i was loosing my mind. i didn't know if lopy cams were a different animal than stock motors. and thanks for the nice words about the car. i said i would never buy another finished car but this one was different. she won a top award at the national show, wheels of the world, back in 85 in washington dc.. its an old school rod all the way. the origional builder spent 20 + years building her. it shows. every day i spend playing with her i find a new detail that the origional builder did. i picked the car up in baltimore a few years ago for my brother in law and found the car was sitting on shag carpet in a storage unit. My only problem with the car is keeping up with the polishing. shes a trailer queen and i am a driver kind of guy. thanks tom
chevy stack, you replied when i was posting. thats exactly what i was thinking. how would i confirm your/my theory? tom
Starter has more resistance when hot, motor has a little more compression and will be harder to start hot, especially when the timing is advanced too far. Once it starts getting a little gas, it would be like Chevyshack said.
cvstl thats exactly how the motor sounds. I usually set my timing with a vacuum gage. the higher the vacuum the more dialed in the timing gets. it seems to work on older high mileage motors. just make sure it starts without bogging down. This is a new crate motor. is that a good way to set the timing on a new motor that has a mild cam? what other methods of setting the timing are recommended? if setting the timing to a mark is recommended. what would that setting be? thanks tom
Assuming that you don't know what the cam specs are exactly...... use a timing light, plug your vac advance, and start with 10*-12* advance. If if bogs on acceleration you can creep up on an initial advance that works from there.
I would take a reading on the battery. When everything is right it cranks. I think it is on its last legs. As to the fuel, my guess is the the carb is leaking down overnight and has to replenish itself. Two different problems. Maybe.
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