75 500ci 8.2lt V8 Fuel Pump question

[lastryde]

Hey everyone,
I thought I may have some issues with the pump on my caddy being it was still the original one in the engine. It has the 500ci 8.2 V8 in it.
Now when I took it out and looked at the replacement that I was given I noticed that the arm was just a little bit shorter than the original and it also did not have the plate that the old arm had on it as well.
I put the new pump in the exact way the old one came out and now I am thinking is there a push rod or something that I may of had to lift before I inserted the new pump?

If anyone has more of a knowledge on this from working on this engine would you be willing to share what you know about it.

Thanks to all!

[tonytheskin]

the pump arm i believe is pushed on by the cam or cam eccentric(sp). The pump arm needs to sit under that, there is usually some pressure felt when trying to install the new one. But, if the new one has a shorter arm, depending on how much shorter that may be the issue for no fuel supply.

[Mohawk Freak]

The plate on the old arm was just to strengthen it. The O.E. stuff was always made better. I seem to recall an eccentric being what drove those. The Chevy type with the rod, if you didn't lift it, the pump wouldn't go in. Gas in the tank? No holes in lines or rubber hose, right?
It may be bad out of the box. The 89 Brougham I have I replaced it a while back. The first one died and would not pump gas after 2 days. The next one they gave me was overpressuring and blowing gas out the bowl vent. The 3rd finally worked and still does 6yrs. later. Pissed me right off at the time though.

[travlinman]

There is no rod. The arm on the pump rides on an eccentric like MF said (which basically looks like a freeze plug bolted offset on the cam under the timing cover). Depending on where the position of the cam is, when Your sticking the pump back, if Your on the high side it will be harder to put in, compress's the arm more. Bump it to the low side and should go in a lot easier. By the way, the ethonal? will eat the old pumps, I had to change Them on both My cars. Also a good idea to change the accelerator pump in the carb, it will get eaten too. They make a special blue pump, the old black ones are on borrowed time. Giving the carb a little drink may help it pick up and save some spinning. Good luck, been there, done that, and doing it again.

[lastryde]

Thank you Tony, Mohawk, and Travlinman. I will give all the advice that you all gave to help me on my quest to get this engine to run. I can get a fire after replacing rotor, cap, wires, plugs, and trickling a little gas into the carb. I have replaced all the lines from the tank to the carb and I know I have flow from the tank through the pump because I got a mouthful of gas just making sure that the lines had no leaks. So either I have a bad pump, something wrong with the cam or the carb needs to be cleaned or rebuilt.

I love these classics but they are never done.

Thank you again,
Lastryde

[travlinman]

If You are sure You have gas to the pump, start from there. If unsure unhook the hose on the pump. Put a section of rubber hose on there and run the other end in a gallon jug. That eliminates the screen in the tank and the fuel lines. There may or not have a fuel filter in the pump, make sure it does not have the anti drain back valve. Remove the fuel line by the carb and add a hose to the end too see if fuel shoots out there. Put a little drink of gas in the carb and start. The fuel in the jug should drop. If it drops and none still reaches the carb, if an air conditioned car, the pump should have the 3rd line on the pump which will bypass back to the tank. Now[whew] if gas reaches the carb, there should be another filter at the carb inlet behind the big nut, famous for plugging up, especially the rock ones. Now if all is good, should have fuel shooting when You open the throttle. If not the accelerator pump may be bad or float is stuck down not allowing fuel in. I know this is long, but step by step should eliminate things as You go.

[lastryde]

Awesome advice! Thank you. I will start there hopefully this weekend if the weather works and it does not snow here in MN.

[Mohawk Freak]

Odds of the eccentric cam being bad are slim. Don't take the carb apart till all other options are checked. That's a last resort thing.
Probably worth a mention if you want to prime the carb with gas, the little vertical tube in the center is the bowl vent. Take the little tit cap from a gear oil bottle and use it like a little funnel to pour gas in there. It will fill the bowl and the car will usually fire up like you drove it yesterday.

[lastryde]

Good to know. Do you have a little more of a breakdown of the exact location of the bowl vent?
Thank you very much.

[Mohawk Freak]

Assuming this is a 1970's Quadrajet, it is the little tube about 5/16" in diameter sticking vertically out the top of the carb. It is almost dead center in the middle, just in front of the choke butterfly. Just pour gas into there gently and you'll know when it's full. It saves a lot of cranking time. If you still aren't sure, I'll take a picture of one.

[lastryde]

IT'S ALIVE!!!!!
Thank you Mohawk Freak for your suggestion of priming the float.
Now...it is idling super fast and hot. I closed the choke butterfly and it sputters and dies but if I leave it open it just idles up around 3000 RPM. The Chilton book I have
does not give me the best idea of where to start or what to do in case of this.
Any ideas or suggestions?
Thanks

[Mohawk Freak]

This forum logs me out faster than I can type this kind of stuff. PM me your E-Mail if you like, I'll walk you through it as best I can and hopefully get you squared up. Once you get familiar with it you'll be good to go.