'66toro

After a long delay due to family illness and extreme cold weather without a hearted garage, I finally got my new timing chain installed on my 425 '66 toronado. I'm about ready to start it so my question is should it start right up after priming the carb or should I expect to have to make any adjustments; specifically, I'm wondering if when it starts, does ignition timing generally need to be set after changing a timing chain?,,,

oldcutlass

It may start right up if the timing is close, and yes you will need to retime and probably adjust the carb.

droldsmorland

Why not take the opportunity to tune it? Dial-in the timing and A/F mixture. Check the carb to intake torque, Look at the plugs, wires, cap, rotor, points, vacuum lines et al. Is the carb ok or is it ready for a rebuild yet?

A common practice for me when busting open a cooling system/timing cover assembly is to seal everything up fill it up then PSI test it. See if it holds then final assembly & start it up.
I generally send the pump out for a rebuild too...its a case of the MAWs but you are on a roll.

Not a bad idea to run the torque sequence on the intake at this time.

'66toro

Yes, good suggestions. I had rebuilt the carb a while back, the car sits 11+ months out of the year but the quadrajet still seems to be operating as it should, smooth, no hesitation, etc. I do plan to install new wires, cap, and pertronix module soon as I get it going and hope I have no leaks,,,thanks again

RetroRanger

Do a search on here about pertronix.

some go years w no issues, some have nothing but issues.

Pertronix. 50% of the time, it works every time!

for the same money you can get an inexpensive HEI or keep the points

'66toro

Well, I got the engine started, but it ran very very rough, I took the plugs out and they were fouled, this was after only running it for 1-2 minutes, cleaned them and put them back in and it happened again, it run smooth/normal (at fast idle) for the first 30 sec. then began to run rough again; I'm stumped! I must mention that when I first tried to start the car, it cranked and cranked and would not start and, not knowing how or why, i found that the hot wire to the coil was disconnected; when i connected it, it started immediately but as i stated, ran very very rough; any suggestions?

Fun71

Did you check the ignition timing while it was running?

Also verify the plug wires are connected in the right order.

'66toro

yea, all plug wires are correct, they were not removed prior to changing the timing chain and the car run and idled fine then; I didn't check the ignition timing because it was on fast idle and I shut it off after about a minute due to the very rough idle,,,

66SportCoupe

Replace the spark plugs then trouble shoot. Might just be bad plugs. Dealt with that situation yesterday.

'66toro

Good suggestion, being a lot of fuel got dumped in when the coil was disconnected and not providing spark, my plugs got fouled pretty much,,,thanks

Dynoking

The spark plugs for sure may have fouled from the unburned gasoline. But if they were half decent to begin with they should clear up on their own. Check and set the timing to at least ballpark. Even simply turning the distributor to see if the engine smooths out is ok for now.
There is a concern of internal engine damage after timing gear failure. Bent push rods, bent valves, etc. This is where a vacuum gauge comes in to give a quick check of the engines compression. A rapid bouncing needle may mean it’s time to get out the compression gauge.
Stick with it, and keep us apprised of your progress.

Ozzie

Is there any possibility that you missed a bit when installing the chain?

'66toro

I don't think so, I was pretty diligent about making sure it was correct, thanks for your comments,,,

deadeyejedi

i know its after the fact but a member here once suggested to take a picture of the timing setup before buttoning things up .Ive done it ever since to avoid second guessing myself.