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Been quite a while since I have been into a Packard engine. I am having carburetor problems. Engine dies when I try to give it a hard throttle. Rebuilt the carb and still the same problem. Checked everything. Replaced the points and check the timing. The timing was advanced to where the timing mark wasn't even visible. Set the timing where it is suppose to be,
The vacuum gauge only measures 15 at idle and states above the mark "Late Timing". Now since we have retarded the timing from before, I am wondering why it was set at a more advanced timing? The engine has been overhauled and taken apart. Does this engine have a timing chain or is it fastened securely to the crankshaft where the timing mark cannot get off. Unless someone replace the vibration damper with a different one, but I would doubt that. Can I put a compression gauge on #1 cylinder to see if the timing mark matches TDC when there is max compression? The service manual does not give an easy way to check this. Hope you can help. Lee

Ross did an excellent video on setting up the timing, so give that a look and see if that helps.

youtube.com/watch?v=XiY11rwjQ6A

Wes

Yes a good presentation. However have a question and not sure you can answer it. Without going through of getting #1 cylinder on TDC and checking timing mark and setting distributor in the right position etc. I am wondering if the plug wires could be in the right firing order but in the perhaps the wrong holes in the distributor cap. If this would be the case, could the engine still run if set on the timing marks? It would be of course either much to early or too late as indicated on my vacuum gauge. But could it be on the right timing marks and still run? I guess that is my question without checking out #1 cyl TDC and timing mark and position of the rotor firing on #1 cylinder. Yes I am a little rusty as everyone else, but hope there is someone out there who is up on this stuff.

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Lee (auto.nut), how about the distributor shaft play?

Distributor is in good shape.

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No- unless the timing is way out of spec. The timing marks are related to crankshaft position relative to #1 TDC. The rotor has to to be firing on #1 as it is near TDC, or the engine wouldn't run.

Believe me, I understand your frustration!

Getting #1 on TDC isn't too rough- it only requires two turns of the crank at most.

If the car is running, you have fuel, air, spark, and timing close enough- everything else at this point is fine tuning!

Edit- your engine has a timing chain. I would start with checking compression on all cylinders, with the choke and throttle head open. Then look for vacuum leaks - that could cause racing, high idle, choking on acceleration, etc. Also, when you look down the throat of the carb, Andover the throttle, so you see jets of gas? If not, your accelerator pump may be bad.

Disclaimer: I'm not qualified. I've made every mistake. I'm learning, BUT

1. I set up my firing order and distributor according the the visual in the manual. I had no idea why the car wouldn't run. Turns out the manual shows the firing order positions on the distributor Clockwise. The engine turns Counterclockwise. On my 356 Super 8, the No. 1 cylinder/spark plug position is at around 7 o'oclk on the distributor and the rotor proceeds counterclockwise.

2. Someone correct me if I'm wrong, but since in every two revolutions of the engine, only one has the No. 1 cylinder at TDC, I determined the position by taking out the No. 1 spark plug, sticking a piece of tape on the fan blade to keep track of one revolution, sticking a piece of doweling in the hole, marking the depth, and turning the engine (I think I did it by the fan blade, but may have hit the starter button with the key off) until the tape came up again for one revolution, then measured the depth with the doweling again. The intake valve is under the spark plug hole, so when the intake valve is closed for the compression, the dowel goes deeper. The deeper measurement identifies the compression stroke and your at TDC.
I'm probably missing some key info here, but that's what I did.

3. My engine quit under load (going up hill) on acceleration because the floats in the carb were not set correctly and I couldn't imagine that being the problem because one of the very best carb rebuilders in the country had just rebuilt it. They fixed it.

4. The distributor is secured by 2 cap screws, the rearward one on the right is kind of hidden by the grease cup. If that isn't tight, when the vacuum advance tugs at the distributor plate, it won't have the desired effect.

Just trying to think of other stupid things I've done.

5. The slit at the bottom of the distributor shaft connects with the oil pump. If the oil pump was removed and replaced, the rotating seat at the bottom could be 180 degrees off. If so, the engine will run Very rough, but that doesn't sound like your problem.

You can try my homie ways, but the best advice is to follow Ross' video step by step.

I have pix of the above if needed for understanding.

Good Morning...You might also wish to be sure that your fuel pump is pumping as it should and that the fuel line is clean from the tank. Sometimes there is enough fuel for idle and moderate driving but not for full open throttle...just a humble thought...Ernie in Arizona

Still need someone who knows the Packard straight eight engine very well. Since I may be chasing a tiger by the tail with rebuilding the carburetor etc, I am concerned however with low vacuum reading at idle etc. At idle around 375rpm I am getting less than 15"Hg and my vacuum gage states above the reading of late timing. I have just timed the ignition however and it is correct. So wondering if I have the timing gear one tooth off when I rebuilt the engine. I wouldn't think I would make a mistake like that but one is not always 100% perfect. If that would be the case, how would I ever determine this without almost having to remove the engine from the auto? To correct I would have to remove the head, all the valves, hydraulic lifters, etc. Almost a complete disassembly! Question is: if I find that the camshaft gear is one tooth off, would there be any easier way to correct? I suspect the gear is bolted onto the camshaft. Could the gear be taken off and the cam rotated by one tooth and then put back on?
Lee

The cam gear can only mount to the shaft in one position, so you can discard that possibility. You could have mounted the chain incorrectly but to correct only requires you remove the timing chain cover but no disassembly of the head, valves, or any of that. Before disassembling anything why not just check the valve timing? Use the engine section of the 1946-1950 shop manual section for the 356 engine, essentially the same as yours.

Regarding low vacuum, have you thoroughly checked for a vacuum leak? Including the distributor vacuum unit? Have you confirmed that the carburetor accelerator pump is functioning?