Ignition Issues

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Conner

Member
Joined
Feb 19, 2024
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Location
Michigan
My Car
72
Hey guys, my 72 has a 460 that I just installed a single carb high rise on and can't seem to get timing right for it to start. New dist, coil, etc. My balancer had no marks on it so I marked what I believe to be my TDC, stabbed dist making sure correct firing order etc. Caught fire at the carb so I assumed I was 180 out, now it still won't start but is backfiring out of the exhaust rather than blowing up my carb, why is that? Could someone go through a step by step so I can make sure I've done it all correctly for initial start? I have timing tape to put on but don't want to install it until I know my tdc is correct. 23yo and still learning a lot about these old beasts, basically my first time ACTUALLY doing timing etc from scratch. TIA!
 
Ok, I think you need to start over, at square one. If you’re really interested in doing it by the book, you need to pull the passenger valve cover so you can verify the #1 cylinder is on the comptpression stroke and at TDC so you can also verify the timing marks. Once you’ve done that, you can pull and restab the distributor, pointing at #1, and then go back to where you left off. Just my 2 cents.
 
I agree with Steve, it sounds like your timing is still wrong. Make sure you know exactly where TDC on the compression stroke is and start from there. Although Ive been 180 out of the distributor before and never had a fire at the carb, so make sure you don't have anything else wrong.
 
It seems odd that you can’t see any timing marks in your balancer. Maybe hard to see because of paint or dirt. Pull the number 1 spark plug and bump the starter until you hear air forced out, then check your balancer. You should see some marks on your balancer.
 
Disconnect the coil wire. Pull the number 1 spark plug. I cover the hole with my thumb and bump the starter...DO NOT PUT YOUR FINGER IN THE HOLE. You can feel the compression. Pull the distributer cap and look at where the rotor is pointing. It should be at number 1 or close. Pretty much what Steve said without pulling the valve cover. If you pull the valve cover might as well check the "valve lash" while you are there. Good luck.
 
Thanks for the advice guys. I'm DEFINITELY at TDC- rotor points to #1 on cap when the tdc mark i made on balancer lines up with pressure output from #1 spark plug hole...firing order is correct, counterclockwise for ford...what else could it be? What about advance on dist etc? Maybe I'm doing something wrong there? Not sure at this point.
 
Was it running before this update? Do you know what cam is in it. Aftermarket Cams can sometimes have a different firing order. If it was running before this did you verify firing order prior to removing wires and distributor?
 
What method did you use to determine that you are at TDC?
Double check the firing order: 1-5-4-2-6-3-7-8 counterclockwise. The big block (385 series) firing order is different that the 351C and W and EFI small blocks.

Point ignition? Make sure the condenser is installed correctly and functioning and the little breaker plate ground strap is installed in the distributor.

I agree with cjstaci, seems odd there's no timing marks on the balancer. There's just a few of them located at the back edge of the balancer.

Another possibility, the timing chain/gears are badly worn and have jumped teeth, making the camshaft way out of time.
 
Was it running before this update? Do you know what cam is in it. Aftermarket Cams can sometimes have a different firing order. If it was running before this did you verify firing order prior to removing wires and distributor?
Hi, I got it to run once but it idled VERY high, I think I messed with dist and now it's back to not starting... Not sure what cam, assume factory. I verified firing order.
 
What method did you use to determine that you are at TDC?
Double check the firing order: 1-5-4-2-6-3-7-8 counterclockwise. The big block (385 series) firing order is different that the 351C and W and EFI small blocks.

Point ignition? Make sure the condenser is installed correctly and functioning and the little breaker plate ground strap is installed in the distributor.

I agree with cjstaci, seems odd there's no timing marks on the balancer. There's just a few of them located at the back edge of the balancer.

Another possibility, the timing chain/gears are badly worn and have jumped teeth, making the camshaft way out of time.
Rotor points to #1 on cap when the tdc mark i made on balancer lines up with pressure output from #1 spark plug hole. Firing order is correct..counterclockwise. I'm sure there were marks at one time, but they've been faded or scratched off, who knows.
 
The tools I use are (1) a piston stop and (2) a piston whistle. The first will help you find exactly where TDC is, no matter what the timing pointer and timing marks say. And the second will help you make sure you're on the compression stroke.

Then, make sure you have the correct firing order, and going the correct direction around the distributor. Make sure the vacuum advance is disconnected, and the port is capped off at the carb.

For the issue you initially described, backfiring out the exhaust, I have experienced that when I had my timing about 15 degrees too early. It ran, but it backfired.
 
Another possibility is that the outer ring on the balancer has slipped around, due to the rubber between the ring and hub drying out and disintegrating.
The timing marks are usually just etched into the metal, not just painted on. The etched marks can be difficult to see, and usually need to be highlighted with paint to be able to easily see them with a timing light.
To accurately determine TDC requires using a tool to stop the piston before it reaches TDC, then turn the crankshaft in the opposite direction until the piston again stops. TDC is halfway between the two stopped positions.
 
I feel your pain, I have been doing this for years and I had issues trying to get my 460 running last year that had me pulling what's left of my hair out...

As was suggested by somebody else, I would pull all the plugs and make sure they are not fuel fouled. While they are out, pop the passenger VC off and bar the engine over and watch the valves on #1 to confirm you are on the compression stroke. When the intake valve closes you can put your finger over the spark plug hole and ballpark when it is at TDC and try get a good look at the balancer for marks. If you can't see any timing marks make one that you can easily see. I try and get the distributor stabbed in with some advance, so the rotor would be ahead of #1 tower on the cap, this should give you a close enough amount of initial advance to get it started. If it does start, I would rotate the engine over to where you can see the mark you made easily and verify that there are no marks that are painted over/ filled with crap/ rusted off etc. Note what also has been said above- if the balancer is old the outer may have slipped and that's why the marks aren't in the right spot.

If you really don't have any marks the best way to add new ones or put a tape on (the tape must be for the correct balancer OD!) is to use a piston stop. Otherwise you won't know true TDC, only a good estimate.

Oh and convince yourself that you've got good strong spark and fuel also!

Good luck!
 
Ford distributors have several teeth on them, not tang and groove (180 out) like some GMs. So you can be 1 to several teeth off and it will still go in. The no marks on the damper is very strange. I've never seen that on this vintage Ford V8. I hope you get it sorted out. Chuck
 
I know you’re getting lots of advice and it can be depressing when you think you’re got it close and get no love back from tje motor.

So, more advice if you may. Pull all of the plugs. Put a charger on the battery. Attach number one plug to its lead. Connect the t8ming light to number one. Point it at the balancer. While not completely required, have a dark garage or low light so the flash will be easy to see on the balancer. Have someone turn the engine over as you put your hand by the #1 open spark plug hole to see if the puff of air corresponds to the spark and flash moment. After days of my 429SCJ giving me no start fits, countless distributor fiddles, I discovered my slipped harmonic balancer this way.

I hope the cause is apparent soon. Good luck.
 
Well, I got it to fire by guestimating 10ish BTDC. After about 10 seconds of running my carb blew off (was not bolted down) bad backfire through carb. Any ideas? Still timing issues? Fuel mixture or something with carb? What do you guys set yours at for initial start? Keep in mind this is a 460 bb. TIA!
 
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