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I have a '52 - 250 and after just replacing my master cylinder, my mechanic said that the fuel pump is leaking.

I am not super handy in working on my car, but I figured that I can get a new fuel pump to replace the leaky one.

So, my main question is: right now she takes forever to start cold. My friend said that it could be that it needs an electronic fuel pump.... my question is, will a new mechanical fuel pump help her start better? I really don't want to add electronics or something that requires maintenance, or could pose problems.

thoughts?

Taking a long time to start cold could be many things (non-functioning or improperly set automatic choke comes immediately to mind) but certainly a leaking fuel pump doesn't help any and may be the sole cause (assuming it's leaking gasoline and not oil) if the car has been inactive for a week or so. So replace the mechanical pump, give your automatic choke a check for function and adjustment if necessary and see if things have improved. Starting should be very fast - just a few revolutions of the motor at most.

Some folks, especially those who live a high altitude or in very high temperature parts of the country like the extra security an electric pump in tandem with the mechanical pump can bring, for instance for vapor lock, and also to aid staring after prolonged layups. Certainly in their day these cars started quite quickly with the mechanical pump.


And....with a fuel pump leaking gasoline, I wouldn't be driving or even running the car until I fixed it.

Assuming the car is driven the day or two before the hard starting, If the fuel is reaching the carb and not all dropping on the ground doubtful the fuel pump is the main starting issue. It could also be the choke is not closing properly or the carb is in need of a rebuild.

On the pump replacement, I would get an already rebuilt exchange pump from Kanter or Max or else send your pump to one of the rebuilders and have it done. If your mechanic is willing you can also get a rebuild kit and he could do it.

Electric pumps are usually added more for convenience than actual running operation. Many have cut the line and added one near the fuel tank to have it push fuel thru the mechanical pump. That way it can be switched on and off with a hidden switch and used only when needed. If you wanted to do that be sure to get the type that allows fuel to be drawn thru when the electric pump is off. Airtex has a couple of 6v models many on the forum have used.

Benefits of adding a second pump are the electric can be turned on for a brief period to prime the fuel system after fuel evaporates due to an extended period of inactivity. This saves wear and tear on the starter since the engine doesn't need to turn over as long to bring fuel into the carb. Another advantage is because of the higher volatility of todays fuel sometimes vapor lock seems to be an issue. The electric pump can pressure the system before the mechanical pump and many times alleviate the symptoms.

OK - thank you! sounds like it may be a combination of the pump and the Choke. And I believe that it is oil that is leaking, because it is not gas. I will get a new pump from max.

If it was running within 24-48 hours, it will fire up pretty quickly, but much longer and it will take forever.

Thank you for the input!

Here's a good starting point;https://www.packardinfo.com/xoops/html/downloads/EngineDiagnosis.pdf
The Service Training Manual has a Tuning and Troubleshooting Section that's very helpful. My 47 will sit for weeks and after a little cranking, the fuel is pumped up to the carb and it fires right up, no need for an Electric Fuel Pump. When I would drive it more often after setting for a day or two it would fire up after a few cranks. A Packard engine properly tune should fire right up without much cranking. Is yours a button or gas pedal starter. It wasn't until I read up on starting a Packard with the foot starter that I found I was doing it wrong and fixed my hard starting problems.

Also here's a PDF on Rebuilding a Fuel Pump which might help.https://packardinfo.com/xoops/html/modules/article/view.article.php?122

Enjoy your Packard.
Wes

Also checkout "Fuel Pump Rebuild PDF filehttps://www.packardinfo.com/xoops/html/downloads/FuelPumpRebuild.pdf " if you're going to just replace your fuel pump, next to last page was some very useful information about reinstalling a pump.

Also I don't know it your pump has them, but on my 47 there are spacers that go on the bolts (between the pump body and bolts). The mounting holes on the mounting part of the body are bigger then the bolts, so watch out for them.
Wes

I have a '52 250 as well. I run an airtex 6v inline with the mechanical pump. If my car has been sitting for mare than a couple weeks, I will let the pump run for 30 seconds or so to get gas back into the carb before I try to start it up. Otherwise, it is always off. The car starts quite quickly.

If your pump is leaking, you have to fix it. An electric back up is your choice. Make sure your choke is working properly and correctly adjusted and that you have no vacuum leaks. You have a couple vaccuum lines that come off the gas jump, so check those for leaks as well. I think if you get that all sorted out, it should start well with or without the electric pump. Of course, if it has been sitting for months, you either will need to prime it or grind it till fuel is pumped up to the carb.