still not starting =(

[zman525]

hello, i posted before about a problem with my 1972 datsun 240z and so far it has not been solved. The car ran a year ago however she doesnt run now. It recieves plenty of fuel and what seems to be good spark. The engine will crank and then backfire unbelievably loud. I have replaced the distributor cap, rotar, plugs, and wires. I thought maybe the distributor rotar was 180* off but i couldnt get it to go on the other way leading me to believe thats not the problem. I regapped the points and rechecked the firing order and everything seems correct.. someone plz help me! =)

[Ricklandia]

Possible the distributor got turned while you were working on it? When you're cranking the motor does it sound like it's "trying" to fire at all? Backfiring out the tailpipe sounds like the ignition timing is severely retarded, causing the spark timing to ignite long after TDC, so much so that the exhaust is loading up with unburned fuel. First thing I would be doing would be to whip out the timing light and check the timing. Pronto. If you don't have one, they're not too expensive at the local parts chain stores (~$30-$35)

[zman525]

say if the timing is off how do i go about adjusting it?

[Ricklandia]

Adjusting the timing is really simple. Loosen the distributor hold down bolt slightly, just enough that you can physically turn the entire distributor housing. Turning the distributor housing clockwise or counterclockwise will either advance or retard the timing. Getting this timing correct is important. It can be done without a light, but that assumes the car is already running somewhat correctly. I'm starting to think your's might have more involved if you cant get it running at all. Is it trying to run at all?

[zman525]

WOOOT GOT IT RUNNING!!!! it was actually wrong firing order. thx for ur help though... now it just runs terrible and have to adjust some stuff

[dogma420]

replacing wires if you are replacing the dist cap makes it easy...setup the wires on the new cap without removing the old one so you have a good reference right there to look at...

[beandip]

say if the timing is off how do i go about adjusting it?

In the future , if you need to find the correct timing for the ignition . Remove the spark plug from # 1 and remove the coil wire from the dist cap . put your finger over the plug hole and have some one " tap '' the starter so it just barely turns the engine . When the piston comes up on the compression stroke you will feel the air push your finger. If you can do this and stop it in time you will be able to see the top of the piston with a flash light. You can turn the engine with a socket on the crank shaft pully nut . Then just align the rotor so it points to the spark plug wire in the dist cap that runs to the # 1 plug. From there you will need a timing light to do the rest correctly . Gary