Packard Forum Index » Post-War (1946-54)

Hi. I'm having an issue with my '51 200. When I hit about 35-40 mph the engine bogs down and loses power. then if I let off the gas and slow down I can accelerate again until about 35-40 and it does it again. It feels to me like its not getting fuel. Things I have done: new plugs, plug wires, points/condenser, rotor, dist. cap., coil, all things that needed replaced anyway. Electric fuel pump was added about a year ago. It's getting good spark, timing is correct, fuel to carb. At this point I am assuming it's something in the carburetor, which of course is the one thing I don't feel comfortable messing with. The carburetor was rebuilt about a year ago with the ethanol safe kit from max merritt. no issues after the rebuild. Anyone have any suggestions on where to go from here. Thanks for any info.

Might also check the heat riser valve and make sure it is opening and not stuck closed. Closed valves can "strangle" the engine making it bog down as well as cause it to overheat. A clogged exhaust system will do the same thing. If the air cleaner is restricting air flow that can also cause some interesting symptoms.

There are many things in both the fuel and spark system that could cause this. get a good service manual and follow the diagnostic procedures, sometimes it;'s a simple as something stuck under the gas pedal. it could also be something you already replaced like a condenser or point not adjusted correctly

Thanks HH. I did't notice any overheating problem, but I will definitely check that out.

Try this::
Take the car for a test drive. When it tries to lose power then vigorously pump the accelerator pedal to determine what results.

If it seems to allow the caar to speed up and even out then i
the problem is most likely ffuel, most likely accelerator pump in carb.

First run the test as outlined above and reportback the results of pumping the accelerator pedal VIGOROUSLY.

As FredKanter ndicates above it COULD be a bad condenser.
If the OLD condener worked just fine then put it back on and try again.

But easy things FIRST: Run the test i outlined above.

And IF it were a bad condeser then there should be some backfireing of the engine.

Thanks PackardV8. I'll try your suggestion although it will probably be this weekend before I get a chance. I will repost will the results. I don't think it would be the condenser as it had this issue before and after replacing condenser.

I would agree with Fred, go to the Engine Service Manual,https://www.packardinfo.com/xoops/html/downloads/servicemanual5154/Engine_IX.pdf
and start there. We could guess at this all day longer and never get it right. I'm guessing Vacuum Advance is bad.
Wes

When checking the timing I had my helper press on accelerator and the mark advanced with acceleration, so I'm assuming the vacuum advance is working. Would you assume the same?