i've got a mirrored 105 block 390c.i. and elec.ignition. i just replaced the 2 bbl manifold w/a 4bbl manifold. when i was adjusting the kickdown rod to see if that would fix my hesitation problem, i decided to look in the dizzy. with the damper sitting at 6 degrees BTC i noticed the rotor pointing at the #6 cylinder(plug wire).
before i removed the dizzy i marked inside the cap w/a felt-tip pen where the #1
sat in relation to the motor. it was 180 degrees the other way! or aiming towards the driverside rear of the motor.
when i tried to correct it,(several times), it would still end-up on the #6 cylinder. is this normal or what am i doing wrong.

FYI: cranked engine untill TDC. installed dizzy to where it sat before i upgraded to the 4bbl manifold. now when i crank, doesn't start.

is it possible that each time i tried to correct it i still managed to put it in 180 degrees off?

finally, about which direction should the diaphram on the dizzy be pointing? i.e. front/passenger, front driver, straight ahead?

almost forgot, i have two different manuals, one shows the #1 on the cap towards the right/rear of the motor. the other shows the #1 on the cap directly in front of the motor. where should it be sitting?

p.s. sorry if some of this is thread is repeating, but it's late and i'm confused.
and any help would seriously kick ash!

 

Ok, sounds like you need to step back and start from ground ZERO!

Pull #1 plug and bump motor till you feel air push your finger off plug hole. Then, make sure damper is at TDC(or real close to it). Now, it makes NO difference where the plug wires are on the cap. #1 can be anywhere you want(as long as the firing order follows correctly). So, go with where your #1 wire is on the cap, turn rotor til it lines up with it and slide dizzy into block. Install cap, #1 plug/wire and try starting again.

BTW, aim the vacuum advance anyway it has room to turn to adjust timing(usually straight forward).

Sometimes when you try to follow things that are outta wack...it's easier to start over.
It will be running before you know it!

 

Some caps are actually marked with the location of the number one plug. This is great if your dizz is installed correctly and you can run your wires from there. If your wires were out 180 degrees to compensate for a dizz out, then you will need to reroute your wires correctly when you install the dizz correct.

--Mike

 

freightrain, i did exactly as you said, and...it worked! started up without any backfiring or hesitation. and with a little adjusting, i'm back on the road! my vacuum diaphram is straight forward at TDC so now i can actually adjust my timing without bumping into something!

thank you, FTE came through for me!

 

Glad it all worked! Sometimes you just have to start at step #1.

 

Looking at an older thread...and came across this one.

My question is how do you know with total certainty that you are at #1 TDC on the compression stroke? As mentioned above...you will feel air push at your finger, but isn't it possible to pull another plug that is also TDC on the compression stroke? For example...both #1 and #??? are at TDC at the same time on the compression stroke???

Just thinking out loud...

Thanks,
biz

 

When the timing pointer is on 0 (TDC) only 2 pistons will be at the top of thier stroke. One is at the end of compression, the other is at the end of exhaust. All of the other pistons will be somewhere in between.