Hi. I've got a 73 f100 that i swapped a 302 and 4 speed into. The engine cranks over fine it just doesn't want to start and run. i know it has good spark and compression and I've found top dead center and have got the timing pretty close I think. Also i know its firing because the engine has backfired from the exhaust and out the carb and it doesn't need starting fluid to make it do that. yet when i took the plug out it smelled of gas but it wasnt black or tarnished at all, but it does have spark. it's like it wants to start it just can't. for a carb I have a Holley model 4160 on a Ford intake off of a 1968 289 and it uses a point ignition system with all new points, dist., coil, plugs and wires. I'm out of ideas and i cant find the problem any help would be great. Thanks.

 

I'd bet you are 180 degrees off on your distributor. double check that the motor is on top dead center on compression stroke (both valves shut) then see if you are close to #1 on the distributor

 

X2, it happens to the best of us.

 

There are 2 different firing orders on 302s depending on the year. I've put the plug wires on wrong and had the same experience.

 

Good spark? Strong fat whitish-blue spark? Lots of bad condensers being manufactured these days. Try an old school original Autolite or Echlin.

Backfire through carb is some sort of timing error, crossfire or firing order. TDC on compression #1 cylinder pointer should align with 0° mark on damper. Not unheard of for old dampers, the weight will slip off axis from the basket, the rubber sandwich between them deteriorates. This will bugger the marks and make timing marks useless.

 

posting just to see Tedster9 invisible post

 

^^ This is what I was wondering too. Check rotor and damper at TDC.

 

at least I've seen other people having the same problem when you post

 

Thanks! ....

 

It sounds like an ignition problem. Think back about what has been done since the engine last ran properly. If the distributor was removed I agree with the 180 degree out analysis. If the condenser was changed, check it out. New doesn't necessarily mean "good". As has been said there exists junk on the market that can cause premature aging to the owner/mechanic.
Try to verify performance of each component independently. Also, it is possible for the ring on the damper to "slip". You can check this by establishing TDC through piston movement. Best wishes. Let us know your progress.

 

do you know what the timing differences are? the engine came out of a 74 truck tho it could have been swapped in that truck for all i know.

also i dont think im 180 out I've checked that a few times but i will again for giggles. i also have a new condenser ill throw on and check. The spark seems to be good. one thing i am wondering is i have a ballest resistor which is 1.6 ohms wired in right before the coil, wondering if that's too much? thank you all for the replys its really helpful.

 

Stolen from utube...

289 1-5-4-2-6-3-7-8
302 (Pre-82) 1-5-4-2-6-3-7-8
5.0 1-5-4-2-6-3-7-8
5.0 HO 1-3-7-2-6-5-4-8
5.0 Truck 1-5-4-2-6-3-7-8
351 1-3-7-2-6-5-4-8

 

yes my firing order is correct but i do wonder, im using a 4 barrel intake off of a 68 289, is there any difference in that from a 302?

 

also when i took the egine apart i dont think i paid too much attention to which sides the heads went on but im sure they are the same and everything bolted up the same. is there a difference

 

If you are getting nothing try the cap 180 degrees rotated. If that doesn't work then try removing the ballast resistor. Lastly, double check your firing order.

You may also want to try getting the timing mark to line up, connecting a timing light, and then rotating the distributor back and forth to make it flash. Set it with the flash happening when you rotate the distributor clockwise. This will get you closest to the right spot.

- boingk