Hi guys.
I own a Plymouth PN 32 4-dr sedan for more than 20 years in Germany and took a lot of great distance rides in Europe. Stayed in Spain, Italy (more than 10 times, also in Sizilia) Dutch, Cechoslovakia, Netherlands France (3 times in Paris) and Austria, Svizzerland and the other Countries along the German border.
After more than probably 20000 miles (not under the sea) I got a problem with the fuel pump.
I just got a new one from "Old parts Tom" and it looked alike the one that was built in.
But going around 45 miles, the fuelpump didn´t do its job very well. There was no fuel coming up to the carb. So the engine was firing and shooting, cause there was not enough fuel. Now we install an electric fuel pump to the mechanical one, and now it works.
What is the problem with the mechanical one?
I do not want to make the seller be angry about this problem, but I drove the car nearly half the globe without any problem, and with the new mechanical pump I only had problems.
Sorry about my bad English.
Best regards from Bavaria.
Schoppi
PS: Is there anybody from the forum that comes to the Oktoberfest? Please let me know it.

If the new pump is not pumping at high speed, the flow must be restricted or the pressure is low. I would check the pressure first when the engine is idling. Pressure should be around 3-4 PSI. If it is lower, the diaphram is weak and needs to be changed. If the gas over there has alcohol in it, it will damage old type diaphrams. If the pressure is ok then the flow must be restricted. The pump has a fine screen in it and may have gotten some dirt in it. You have to take the pump apart to look at the screen. The only other problem, but unlikely, would be the cam lobe that drives the pump is worn or the fuel pump arm got bent when you installed it.

Hi hwellens.
Thanks for your quick answer.
My Plymouth is a PB, not a PN.
I just tried to do the works you wrote, but it doesn´t work without the electric fuel pump. Also the idling arm is ok.
I think I have to choose the only possibility, to drive now with the electrical pump.
Thanks from sunny Bavaria
Schoppi

Hi schoppi28!

Don't give up on your fuel pump yet. I have a'36 Plymouth P2 and a '31 Buick 8-57, and have struggled with the fuel pump on both! Both cars run beautifully and reliably now.

At this point in your own struggle with your PB's fuel pump, I suggest you consider sending it to a professional shop to be checked out. The previous owner of my P2 said that he had gone through 3 fuel pumps and blamed the diaphragms for their failure. My own (former) mechanic told me that the cam shaft eccentric that operates the pump arm was worn, after he had installed a new (reproduction) one and it didn't work.

Finally, I sent the pump out, and found the problem was only incorrect internal adjustments. A new diaphragm compatible with modern fuels was installed, adjustments were made, and now the pump works beautifully! While there are a number of places to choose from, I selected "Then & Now Automotive" (http://www.then-now.com). They do excellent work and stand behind it, and are easy and helpful to talk with.

A couple of other things---if the bracket that holds the glass clean-out bowl is over-tightened, the seat will be warped, making an airtight seal impossible without repair, and producing symptoms such as you describe at road speeds.

And the fuel line in an antique car should be replaced with new (check "Restoration Supply Co.<www.RestorationStuff.com> for brass tubing, or use new steel).

There should be a replaceable filter on the fuel line (between the tank and electrical pump, if tou have one).

I was at Ramstein Air Force Base during Oktoberfest a couple years ago, and toured around. I will be in Stuttgart the end of November this year, and will be checking my email. Who knows? maybe we'll meet over there! Good luck!

Hi Fr Mike.
Thanks for your answer and the interesting interpretation of the fuel problems.
I think, I should try all the options you told me.
Shouldn´t be easy from Germany, but think it would worth it.
If you´ll come to Germany, let me know.
Please contact me at schoppmeyer@aol.com.
Best regards from Bavaria.
Schoppi

Hi Schoppi!

My October/November trip to Stuttgart is having to be postponed for now. Bavaria is so beautiful, I really wanted to be there earlier.

Regarding the fuel pump: Ich wurde gerne von Ihnen horen.