1972 fuel pump replacement

[72' Betty]

I'm 16 and got my dream car just last week and I had it in the shop to replace the gas tank (was rusted inside but not outside), fuel sending unit, gas lines, and fuel filter, because the previous owner just left the gas tank to rust and every time he'd start it that rust would go through the whole fuel system. Anyway got it back today and it idles perfect but when it warms up or gets to around 35 to 40 mph it starts missing and the power drops right out, cant make a turn up a hill or go up a slightly steep incline. Itll get the power it should have for a split second and drop off to almost stalling rpms. I'm almost 100% sure this is a fuel problem which means that all that rust must have clogged up the fuel pump and trashed it. How easy is it to get to the fuel pump and how difficult is it to replace.

TLDR: How easy is it to replace the fuel pump on a 1972 429 engine?

Thanks guys I've been looking around this forum for a long time, I've loved Thunderbirds since I was in elementary school.

 

[Dozertech]

It really isnt that difficult. It is more of a feel game than a seeing game when it comes to a couple of the bolts holding it in. Only advice I can give from behind my keyboard is get everything clean otherwise you will have oil leaks till you take it back off and do it again. The fuel filter should be right at the carburetor where the fuel line goes in. That is much easier than the pump to replace.

I would be looking at the points though. They are notoriously unreliable

 

[72' Betty]

I meant fuel pump sorry, I already replaced the fuel filter.

 

[OneAmongOthers]

Fuel pump is a bit of a pain to get to. Not terrible hard. The heater hose is somewhat in the way. Its best to disconnect the power steering pump and move it out of the way. Also I guess the air conditioning compressor is in the way as well (wasn't for me due to it being already long removed from the car). Make sure the lever is on the right side of the cam when reinstalling the pump or you can cause a lot of damage.

It seems some what odd the pump only gives you issues at higher engine rpm and not anywhere else. It sounds more like a carburetor issue or specifically the accel pump not functioning right and starving the car of fuel when you get on it. Try cleaning out the carburetor first, and also try some Marvel Mystery oil in the fuel tank for a couple of tanks of fuel. Couldn't hurt. You can also test the fuel pump by pulling off the line and cranking the engine to see if fuel comes out. Just make sure you disconnect the coil so you don't start the car.

 

[72' Betty]

I'll clean out the carb and see how that works and if that doesnt help I'll look at the accelerator pump and put some of that mystery oil in the tank next time I fill up. The past owner put a brand new edelbrock 4 barrel carb in it.

Thanks for your advice, I'm not very good at sensing what is causing the problem but I know where everything is at on the engine.

 

[OneAmongOthers]

How old is the carb? Modern fuel is terrible with the ethanol they put into it. It destroys carburetors and old school fuel pumps. Get a fire extinguisher and have one in the car. I feel any old vehicle (and vehicle really) should always have a fire extinguisher on hand. Vehicle fires in older cars is more common due to old fuel lines or the fuel pump going out. I had my fuel pump go on me and let me tell you its scary because if the seals go you don't even know and fuel will leak everywhere. The fuel pump is right along side a hot engine.

 

[72' Betty]

The carb seems to be less than 2 years old and a fire extinguisher would be a good idea I'll keep that in mind. When I got thr car the fuel line into the carb was leaking fuel but we replaced all the lines and clamps.