O.k. guys.. for those of you who know.. i need some serious help.. i have a 72 4 dr jsut rebuil the 250 6 cyl motor. everything appears to be working but she wont fire up. heres what i have found. i DO have spark , fuel, air. timeing appears to be my problem so i have checked a few things.. i set the #1 piston top dead center and dropped the dist. in with the rotor pointing to #1. cranked her over and no startup. checked under the cap and rotor is pointing 180 degrees off. pulled the distributor and reset to #1. turned her over again.. no startup. rotor is AGAIN pointing 180 degrees opposite. the firing order is correct and i AM getting spark. my question 1) what am i missing?? 2) could the distributor be bad? was working when i pulled the motor. i DO have a pertronix setup for it but i was waiting to make sure she runs first. again.... HELP!!! many thanx
did the distributor work before? you could pull off each plug and wire and see if they are sparking? how are you checking spark now? coil wire? the distributors gonna be off if you just crank it and just pull the cap.. of course its not going to be back where it is. it will sit were you left it... sorry if i'm not understanding you right. anyways if you keep cranking it will end up back at #1 then check the pistion. if its not at TDC / #1 they it is 180 off then bump it again until it gets to TDC put the distributor in right and try cranking it again.
sorry for not being clear.. each time i reset the piston to top dead center and it was off 180 degrees. didnt pull the capp off till piston was top dead center. i checked each plug wire for spark as well
correction.. i didnt realize two revolution to crank for one of cam. that explains the 180 but why doesnt she start?? im stumped. the distributor did work before. the car was running but using way too much gas and oil. i had to clean plugs every other day. thats why i tore it down and rebuilt.
right! have you checked your firing order? also are you sure the distributor is siting on the right place on #1? it also could be a tooth off but most likey not. but it doesn't hurt to check. when you say it doesn't start does it at all backfire? or does it almost start? or is it just cranking starter noise and thats it.
its jsut turning over.. not even trying to start.. just out of curiosity tho. the spark was orange from the wire to the metal. is it suppoed to be that way or is it supposed to be blue??? firing order is clockwise. 153624 . i believe that is right. have it set that ways anyways.. sitting on #1 dead on
It could be at the top of the cylinder and still not be at top dead center on the compression stroke.
Are you putting your finger in the #1 spark plug hole and verifying it is on the compression stroke when setting the dizzy? When you feel the cylinder getting compression turn your damper by hand until the timing mark is at 0 on the pointer. Your engine is now at TDC on the compression stroke. Install dizzy and point rotor directly at cylinder #1. This should be close enough to get it started but you may have to move the dizzy left or right several degrees while cranking to get it to fire.
Let me add a little detail. Now that you realized that the crank spins twice for every turn of the camshaft you can now see that the piston will be a TDC on the compression and the exhaust stroke. Are you sure you have the coil wired correctly? Distibutor goes to the negative side of the coil.
i appreciate the input guys.. when i get home from work tomorrow i will try to make sure these guides are right... to avoid the crossing wires problem.. i put the old coil and points back in. one side says bat... the other says dist.. cant confuse that... but thats nice to know when i put the new coil in tho.. i was unaware that dist went to negative side. im pretty sure i have it set on tdc on compression stroke.. but i will definitely make sure tho.. do i need to remove the dizzy before doing so? or can i just readjust after i get it to compression stroke? i am going to try all of this tommorrow..anything else i should look for?
Points suck. Setting them with a dwell meter is far more accurate. If memory serves it should be 38-42 degrees but check on that, its been a long time since I set points. You dont have to pull the dist to check TDC on the compression. Just make sure the switch is off.
update on progress so far.. i did my best to ensure that it was turning on compression stroke( kinda hard to do by yourself) but the first time i turned her over with the key. she gave to coughs then nothing. tried several times and nothing.. not even more coughs. i set the dizzy three ways to sunday and got bupkus. any ideas?
If it is coughing it is wanting to start. Orange spark should be enough to start it. Make sure the points are adjusted well. Have you actually dumped a little gas down the carb prior to trying to start? Dan
