Mochi

So I'm on the engine part of Lorayne's buildnup and have replaced the cam with an edelbrock rpm performer cam. I went to put the fuel pump on today and after a bit of trying I realize it's just not going to fit.

Do I need to swap out for an elelbrock pump? What are the advantages or disadvantages to using an electric fuel pump vs a mechanical?

MDchanic

Is the cam all that you've changed?
Did you add Edelbrock heads as well?

Changing only the cam should not affect fuel pump fit.

- Eric

jag1886

If you can't get the pump in the engine, bump the engine over you may be trying to put it in when the pump eccentric is on the high side.

Mochi

Cam and intake manifold is all. I'll try turning it and see what I get.

joe_padavano

It "doesn't fit" because you're on the high side of the fuel pump eccentric. You don't even need to bump the motor. Just push harder on the pump while you install it to compress the internal spring.

Did you install a double roller timing chain? Some are too thick and rub on the pump lever.

Mochi

Ah! Ok I'll try that. And yes on the timing chain. Which is why I was also thinking I need to replace the fuel pump.

joe_padavano

And here's an example of why you need to provide COMPLETE information when asking a question. You may not be able to fit a mechanical pump if the double roller chain it much thicker than stock.

Mochi

So then i should just get an electric one? Or get one from Edelbrock?

Mochi

Just cursing by my old posts and figured I'd update folks after years of fun. I finally decided that I HATED the electric fuel pump and went back to the mechanical. I must say I never got the benefits that most claim come with an electric pump. IE better starting on cold days. IMHO stick with the mechanical unless you have a real need to go otherwise.

Fun71

No one mentioned it in the original thread so I'll say it here so anyone in a similar situation has the info.

Some double roller timing sets cause interference with the fuel pump arm due to their thicker chain and gear. Slotting the fuel pump mounting bolt holes allows the pump to mount slightly forward, thereby giving clearance for the pump arm.

Mochi

Ok guys, I've messed something up and for the life of me I can't figure it out. Here's the rundown.
I swapped out the electric fuel pump and went back to the mechanical one. its installed bowl facing up above the arm.

Everything worked well and I took her around the block to make sure.
Then I started mucking around with electrical system trying to find what was draining my battery every time I let the car sit for 3-5 days.

I removed powere from my aftermarket stero. And then she wouldn't stay running. She would be really hard to start almost like no fuel so I checked to make sure the fuel pump was functioning.

I bypassed the horn relay, ran a new main from the alternator, replaced the alternator, and replaced the ignition voltage regulator. She still won't stay running and now I have white smoke out of the driverside tail pipe.

I'm stuck I've traced all the wires I can think of to see if there is an electrical issue and at this point I'm wondering if I have the pump in upside down or something.

Can someone elaborate on proper fuel pump placement, pictures would be great. I'm confused on this because some say the pump is upside down on an oldsmoblole but to me mechanical pumps on Chevy are upside down, bowl facing down below the arm. And if anyone have any suggestions on the issue that would be awesome.

joe_padavano

In our Chevy-centric world, that is what most people consider "right side up".

The bottom line is that the Olds pump mounts opposite of a Chevy pump. In fact, this is a theme. The Olds distributor turns opposite that of a Chevy. The fact that it ran before you mucked with the wiring says that the fuel pump is fine.

Does your car have HEI or not? The first thing to try is to run a wire from the +12v terminal on the battery to the coil + terminal (if you have an external coil) or to the BATT terminal if you have HEI. Now see if it runs. Note that you will have to disconnect this wire to turn off the engine once it starts.

Mochi

I have the flame thrower petronix 2 on her and coil. I'll try the wire from the battery. I did just notice that the carb is flooding badly so I'm going to swap the filter and check the psi.

Mochi

Joe it ran with the wire attached. And it runs without it now. But I went a bit extreme. The carb was flooding horribly so I went and got another one, this time with an electric choke. I replaces the plugs, all of which had been fouled and now she seem to be happy again. I have to finish cleaning up the wires I pulled apart but I feel better. Thanks for your advice.