I had another thread where I had installed a new dizzy last summer, and found that slowly it had backed off or turned to the point where the base timing was 4* ATDC. I found this out as suspected the new dizzy may have had a bad ignition pick up coil. I installed the old dizzy and put it in exactly as the old one came out. I was always under the assumption with a SBC you could only install the dizzy two ways, one correct and the other 180* out.

Anyway after getting the vehicle running perfect today I happily drove to the gas station to fill up. I got home and decided to put the new dizzy that I took out (thinking it was just a timing issue and not a bad pickup coil), I got it installed but it seemed off a couple of teeth from the position the other one came out. I verified this because the only way I could get it to start is buy turning the dizzy so that the ICM was facing the drivers side, it was almost facing the firewall. Now I can't get it to start?

One thing I hear when turning the dizzy with the key on is the fuel pump prime....what causes that...cam position sensor.

So it looks like I have to pull the #1 plug out and to find TDC, I put the balance mark back to 0 and dropped the dizzy back in with the rotor facing towards #1, but I still can't get the car to fire up...turns over and back fires...which makes me think it is 180* out again.

 

Distributor can be installed many ways depending on where you want the #1 plug wire to be.

Pull the #1 plug and bar the engine over until you know you are on #1 compression stroke. Some tissue in the spark plug hole works well as it will get blown out on compression stroke. Now manually bar the engine over while looking at the timing pointer. When the line on the balancer lines up with zero degrees, you should be very close to TDC. Without a degree wheel, a piston stop and a bunch of time, you'll never know if it's exactly on TDC. OEM timing marks are never 100 percent accurate.

Once you determine the timing is at TDC, rotate the balancer until the line on the balancer is where you want your base timing to be. If base timing is 12* BTDC, the line on the balancer should be at the 12* mark. At this point the engine is now ready to have the distributor installed.

Remove the distributor cap and drop in the distributor until the rotor is pointing roughly where the #1 plug wire is. You may need to use a flat tip screwdriver to turn the oil pump drive to drop the distributor into place. Now remove the rotor so you can see under it. You will see the magnetic pickup pointers. There will be 8 of them. Rotate the distributor until they line up making sure you don't turn it too far to move the #1 plug wire position too far away. Clamp the distributor down. The engine is now timed enough that it should fire right up. Reinstall the rotor and cap and all the plug wires. 18436572 in a clockwise rotation. The engine should fire up but you will still need to use a timing light to readjust the timing due to slop and wear in the timing chain etc.

 

Thanks for the tissue trick, I was going to pull of the valve cover to see if both valves were closed. That will definitely save me some time. Just curious what causes the fuel pump to prime if the key is on and I rotate the distributor?

 

I took out #1 plug and left it hanging by a thread so I could hear it hiss as I rotated the crank by hand, saved me from pulling the valve cover to find TDC. As I suspected the rotor was pointing at 8 instead of 1. As it came up I placed the timing mark at 6* BTDC, dropped the distributor back in place (meshed right in all the way to the oil pump), buttoned it up, and it fired first turn of the key. Put my timing light on it and it was at 2* BTDC, adjusted to 6* and all is good. It really idles best at 8* but I left it at 6* with the ESC disconnected. Reconnected and test drove, seams to be good with the old distributor with new cap, rotor, and ICM. The new distributor I purchased at Autozone last summer still looks brand new and no signs of wear, the pick up coil must have shorted out or something as it definitely was causing the misfire issue i was trying to chase down. Luckily it has a lifetime warranty so I will take it back and get another one to keep as a spare, or refund.

Thanks!

 

Davis unified distributors are a good replacement as well as acdelco. You never know what your going to get with China and Mexico parts but not much available on the market for that distributor.
autozone if Cardone not real good quality.

 

good to know, I will just ask for a refund and then buy a more reliable unit. I didn't realize the Cardone was such trash, the actual distributor looks really good, but the electrical components are not. Frustrating.

 

The ECM received a distributor reference pulse (DRP) and enabled the fuel pump.

RBob.

 

Thanks, does it receive the pulse from the cam position sensor? something must be picking it up because with the key on I can twist the dizzy clock wise and counter clock wise and could hear the fuel rail prime each time. My pressure doesn't hold on the rail, I'm assuming that whomever replaced the fuel pump used a pump without a check valve. So it primes each time to 45-50 then bleeds down. Car other wise starts, idles, and runs fine.

 

No cam sensor on that engine. It is a distributor reference pulse, which is basically a crankshaft position sensor. When you spin the housing that is the same as if the engine was turning/running. As that causes the internal shaft to spin.

RBob.

 

Thanks!