Hello hot rodders, name is Ron, I have a sbc400 that won't start, just cranks and slowly starts to crank as if the battery is dead, I recently replaced the head gaskets on the car along with other gaskets, pulled the distributor and nothing, starter, alternator ,battery and spark plugs also replaced, I've tried putting the car at TDC and nothing, just cranks and won't start, I'm stuck and have no idea what else to do, any help or ideas would be greatly appreciated. My car was running fine and then slowly started to drag, a big white cloud shot out before I parked it and started to work on it, and so now I'm here.
You should be at least getting some type of clue that the engine is hitting on some cylinders and igniting the fuel mixture. First thing to check, since you did not mention it, is if you have spark. Then fuel.
There is fuel and spark, twice I had the car running for at least 10-15 seconds and it shut off Sent from my SM-N910V using The H.A.M.B. mobile app
An engine will run if it has spark, air and fuel at the right time. Start with the basics. Pull a plug wire off and attach it to a spare spark plug and ground the plug to the engine and turn the key to crank it. If there is a spark at the plug you can assume there is spark to the rest of the cylinders. Next look into the carb and work the throttle linkage. You should see gas squirting into the carb throat. If you see gas then assume the timing is off. Align the timing mark on the harmonic balancer with TDC on the timing tab. Either #1 or #6 piston will be at TDC and ready to fire. Remove the distributor cap and see if the rotor is pointing to either spark plug wire. You had to have removed the distributor to replace the parts so my guess would be the timing is off.
does it (when you are turning the key) go...ruut ruut ruut if and when you pull the cap( and you can pull it at ANYTIME) the firing order is 18436572 ... my guess is you'RE not far off (because you said it did start and run 10/15 seconds) and IF the wires are on correctly big if the rotor should be close to any terminal the 1/6 up or timing mark on the tab is the easiest for most... (turn the distributor clockwise about an inch or inch-n- a half) if it ran those 10/15 seconds it's PROBABLY not out the usual 180* issue that is common.
When I turn the key it does that, ruut ruut, my battery is charged and it kills it when I'm cranking the engine Sent from my SM-N910V using The H.A.M.B. mobile app
(turn the distributor clockwise about an inch or inch-n- a half) being OUT of time, advanced to far, makes it do that, ruut ruut ruut, and it draws more battery juice out of the battery, if you can SAFELY leave the battery charger hooked up during your WORK EFFORTS assuming you HAVE a battery charger, do so.
and when you say "my battery is charged and it kills it when I'm cranking the engine" can be terminals not clean-n- TIGHT...
It sounds like your piston rings have gone bad and you have lost compression. i may be wrong but you should check that cause it can happen over time and slowly lose power. and smoke coming out the exhausts last time it ran sounds like oil leaking through the rings.
It's a timing issue or you have the plug wires wrong. You have fuel and spark because it fired briefly. You just don't have it pointed in the right direction. I remember many years ago that after a rebuild on a 283 I couldn't get it to fire at all. Had my brother in law come by and he pulled the distributor out and dropped it back in and the bitch fired right up. We made sure we had compression on number 1 and dropped the dist. back in and we were done.
I just recently got a old 283 running too and had the same firing on a couple cylinders sometimes, and it was the condenser was bad. But assuming that he has fuel air and the timing is correct and the camshaft is not flat i think it is compression and probably worn out rings if not a warped head from over heating. Sent from my LGLS740 using The H.A.M.B. mobile app
A good battery should crank it long enough to completely burn up the starter. Don't crank it more than a few seconds - if it's not starting it won't magically start. They only magically not start. did you adjust the valves correctly? Do a compression test to verify mechanical correctness and soundness. Double check that it's in the correct position. #1 up tdc on compression ( both valves closed) and set the distributor again. It's easy to get it wrong when your frustrated. Just as easy to get it right when you're thinking clearly. Double check the firing order. What did you do to it after this?
Get it at top dead center. Take off the distributor cap. Note the position of the rotor-1:00, 3:00, etc. Put the cap back on and plug the #1 sprark plug wire in the distributor that matches up to where the rotor was pointing. Then going clockwise, plug in wires 8,4,3,6,5,7,2. Then double check the firing order and crank away.
Back up a bit. The spark in free air needs to be bright and fat and snappy blueish-white. Red/orange/yellow, is no good, it won't be able to jump the gap when under compression. You didn't ask, but starters are not rated for continuous duty, and will get smoked easily. This will save you money, consider a well tuned engine starts in a split second, if it doesn't continuous grinding on the starter will play hell on the solenoid and battery too. If by chance it eventually does start the alternator will be slammed trying to charge up a dead battery. It really is a lesson in how a simple small problem can snowball. Rule of thumb is 10 minutes rest after 10 seconds of cranking. Not trying to beat up on anyone just save them some aggravation and expense.
Was the big white cloud oil or coolent? Why new head gaskets? Sent from my iPad using The H.A.M.B. mobile app
OK I will throw this one in because I have seen it happen. Friend was trying to start a SBC and had the same symptons. Would crank and act like the battery was getting low. I checked the dipstick and it was above full mark and smelled of gas. Plugs were fouled. Found out the caburator (Holley) was leaking down and the motor was hydro locking because of gas in the oil. Changed Carb and changed the oil and filter. Cleaned the plugs. It then turned over faster and started. (one hell of a clean engine inside) He was lucky the cylinders didn't wash down.
I didn't see this mentioned,but did you check the valve adjustment,I ran into a problem once , I had them to tight.Just a thought.
Once you have confirmed that the engine is able to start and should run set the engine 10* before TDC and set the rotor at the #1 plug position. I make a mark on the dist housing under the #1 pin position.
I have see people do this more then ounce, with hyd. flat tappet cams. Check timing as advised, and check valve adjustment. Some times one half turn after zero lash is to tight, try going a quarter turn at zero lash.
Start from scratch!! Pull all plugs ,,, ( when time to reinstall start with new ones ) Make sure to be on top dead center , Look where rotor button is poiting , # 1 can be timmed any where on cap Start yr firing order from that point !! 18436572 Put yr fingrt over #1 plug hole turn moter by hand with Breaker bar-ratchet clock wise untill you fill presser on finger , then lock & balancer, turn on till on ""0"" Aline # 1 poll on cap with rotor button, By turning cap back & forth , to adjust , Then snug tight distributor , Look @ where pointer is on ballacer 0 ( hope yr pointer is correct or close by + or ~ 3 degs. Back motor (counter clockwise)up to about 30degs then turn motor clock wise to about 8 to 10 degs on tab , snug tight distributor hold down , just enough that it won't turn when motor starts !! Remember Yr #1 poll laction !!! Hydraulic cam /lifters adjustment Readjusting yr rockers , "" back them all off "" 1 turn or so , So you can turn rocker off push rod,, Start from # 1 Then #3 then #5 then #7 Then so on 2,4,6,8' take And put breaker bar on crank bolt ( plugs out ) Rotate motor clock wise ""Exhaust #1"" with finger on Push Rod , you will start to fill push rod come up to full lift , then AJUST # 1 Intake vale , turn rocke back on top of push rod take and pull up & down on push rod and at same time turn rocker nut with a 6inch wrench / ratchet untill you fill no play in push rod to rocker arm """0"""". Then put yr wrench in the 6 o'clock position turn to 9 o'clock 1/4 turn (( for wright now)) Then turn motor with breaker bar / ratchet With yr finger on top of Exaust push rod until You fill the push rod go down & stops moving, Then move rocke on top of push rod ,Then move the push rod up and down as you tighten the the nut until no movemint on push rod felt , Put the wrench @ 6 o'clock position turn to 9 o'clock ""stop for now , "" Then go to # 3 and repeat , the # 5 & so on ,, Now all yr valves will be close adjustment for start Up , Install covers In stall yr new plugs with gap of .35-.040 then wires 18436572 Turn key on make sure you have power to coil Fix as necessary ,, Give 1 long squirt of gas ( carburetor ) PS !!! Make sure no vacuum leaks and you're off idol just a little bit !! 850-1,000 rpm's Motor should fire right up !!! Once motor fires up set your timing ( it should be set now anyway , NO timming light needed) I always run about 10° to 15° On stock SBC , But I would set it @ 10 degrees , this also depends if your pointer is correct at the balancer !!!! Once engine is running & it can start up again , shut motor off!! Remove Val covers put another quarter of a turn on all Rocker arms , (( A half a turn is this plenty total ) Does not need to be a full-turn , Air ,fuel ,spark & timing ,zoom zoom !!!!
Hydro-locking occurs as a result of enough liquid fuel or coolant accumulating on the top of the piston. As the piston approaches TDC on the compression stroke the liquid can't be compressed and everything comes to a screeching halt. Oil diluted with enough fuel could cause slow cranking due to loss of lubrication. But it seems like it would be as a result of the bearings and rings starting to fail, especially at cranking speeds. A leaking mechanical fuel pump diaphragm can also allow fuel to enter the crankcase.
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