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I just got my car back from having the exhaust manifold replaced because it was leaking. The car is running fairly well but it seems as it could be more peppy. It seems to be laboring at 55 to 60 mph.

I hooked by a vacuum gauge by disconnecting the tube to the wipers. The needle is not steady (wavering) and below normal, which on the gauge reads “late ignition timing”.

Any ideas on what to do.?

Both the car and me are 73 years old, maybe I should be happy with what I have.

You members are always so helpfull, so I humbly thank you in advance for your comments.

Without knowing the condition, the vacuum level(number; inches of vacuum) or last tune-up/maintenance can't really say.
Apparently it gets to 55-60 but not as quickly as you expect but doesn't miss/knock or anything?
Too many things can be at issue to tell with this level of info. Intake could be cracked or leaking if the exhaust was bad, or some other undiagnosed mechanical fault. Fuel can be stale or wet, vacuum leaks, advance leak, compression getting bad, clutch adjustment, etc.
I'd "tune it up" put new points, rotor, cap, and plugs and wires(check), set the timing, check/adjust the carb and replace fuel filter and see how it fairs. Top up with some good quality gas. If not good, check the compression.
In the old days, we used to "blow out the carbon" which in effect was a hard run to remove deposits that accumulated from idling and low speed short trips.
Sometimes things improved.

For sure some basic tuneup steps are in order even before changing any components. A 288 should not be laboring at those speeds.

Make sure the felt pad under the top cover of the air filter has not come loose and is blocking the carb. I've seen that several times.

With the engine idling very slowly check that your timing is at the 7 degree mark. Rev the engine a bit and the timing marks should march a good ways past the pointer. As you snap the throttle shut the marks should immediately jump a good ways back and and then return to 7 degrees as the revs drop. If it does not behave that way, the vacuum advance has failed which will make for very poopy performance.

Your wavering vac gage implies that the idle mixture is way off; you can easily adjust the idle mixture screws to obtain you best reading. A rhythmic drop of the needle indicates a valve problem.

The car doesn't have the faintest idea that it is 73 years old and only wants to be in standard condition. Generally that is easier to achieve for cars than people.

Well said Ross! Ernie in Arizona

I thought about this yesterday but already had too many items for the available info, but a simple inspection of the tailpipe, for black and/or soot will tell if it's intake restricted, aka, running rich. That'll usually back into the plugs getting sooted, too. They get conductive and don't spark cleanly. Sometimes it'll burn off and sometime it stays, if too rich, needing attention, but that's usually more a lag or sluggishness than mid range acceleration/power issue. Could be just how the problem was described or who knows what was done or not done at the shop?
But this is why we used to do tune-ups, because they didn't run good forever in that period like they do now.

Is "poopy performance" a technical term? It's looks like a technical term from here.


And a much politer term than ones heard by Fred the Cat.


I hope that you're not sucking a bit of wind on the intake gasket.

Quote:

How would one determine if the intake gasket is an issue? I ask because I likely need to do a tune up on my car as well. I hit most of the major points listed above when I first got it running, but I haven't done much over the past year besides drive it. I'm enjoying the conversation here...it gives me a few ideas to hopefully improve the running of my car.

You can try re-torquing it to see of the nuts were loose. Not an actual test and I'll let the experts chime in on that but is a place to start. It seems to me that if the problem started after installing new exhaust, then maybe an already-loose manifold could have been disturbed.

By attaching your vacuum gauge to the line going from the manifold to the vacuum pump on top of the fuel pump, you can measure manifold vacuum.
Just do a search online for diagnosis with a vacuum gauge and you will find there are ranges of vacuum defined for different engine operating conditions. Such as ~18 inches mercury at idle. 23-28 inches in overrun etc.
If idle vacuum is low it could be due to late ignition timing or a bad idle mixture adjustment. (say ~14-16 inches) I think really low vacuum at idle could be due to an intake manifold leak. (10-14 inches) A motors manual also has a nice chart on this to refer to for our type of cars.
With a vacuum gauge, a timing gun and dwell meter you should be able to get a packard tuned up properly. A hand held vac pump is also a good tool to check the health of your vacuum advance.

Th is is a photo of the connection from my manifold to the exhaust pipe. I recently had the manifold replaced as it was leaking. It seems that the gasket in between is not tight.

Would this cause the engine to be just noisy or could it cause poor performance. ( It seems to lack power)

Before the manifold was replaced the engine had a tune up with all new parts and ignition wires were replaced.

You members are the best and I thank you in advance
Picture needs to rotated up..

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