fuel pump questions

[mild67]

Im looking at purchasing the followinghttp://m.summitracing.com/parts/mrf-mp-4501
Do I run a return from the check valve on the pump to the bottom of my tank?
I have a sump on my tank with 2 fittings.
Also mine is a 67 and has no vent on the tank, do I need one? Where/how do I fit one?

[boofhead]

I would expect it would require a return line. 18psi is to high for a carbi and to low for efi. A good regulator (internal I think in this case) will use a return line. As far as your tank - no idea how to help - not sure what your have purchased.

[ozbilt]

You can always run a return line into the filler neck. Just remove the neck & weld a fitting into it. Saves modifying the tank.

[mild67]

I have a orig tank with a sump welded on to the rear bottom of it.
It has 2 outlets, 1 is used for my fuel supply the other is just capped.
I can use it as a return but would the return be ok pushing into fuel or at top where theres less pressure?
The pump itself has a return valve I think I just plump that to tank so I dont need to return from carby! Sound right?

[hybrid]

Pushing back in at the bottom should not cause an issue.
A return from the pump does not sound right unless the pump has a built-in regulator.


Edit: Just read the specs... it has an adjustable by-pass to stop cavitation. That might work with a dead head regulator up front.
Might be worth asking summit for confirmation though.

[ozbilt]

Pushing fuel back into the bottom of a tank is no problem as the tank is not under pressure. I have run a return line on an EFI engined Mustang back to the drain hole on an original tank with no issues.

[mild67]

That's what I'm hoping. Im currently running a holley black with a deadhead reg. It's to noisy.
I was thinking the magnafuel pump would be good so I don't have to get a bypass reg and run a return from the carb.
This way I just run one from the pump.

[mild67]

What can I do to vent the tank? I think the caps vented.
Can I put a fitting into the rubber from filler neck and run a hose lick a diff breather to outside of car and puck a filter/one way valve on the end?

[ozbilt]

If you have the standard cap, it is vented.

If you also look at the face where the cap fits the neck, you will see a depression in the outer ring. That lets air in & out ........

[boofhead]

I agree with everything. I know Kerry's return idea works quite well because he did it on Georges car - when I first noticed it I though it was a great idea (and still do - simple is always good). My EFI return line has been silver soldered into the original pickup plate right next to the original pickup fuel line. It works fine as pointed out the pressure is not an issue as the tank is not pressurised (even then it would not matter). The only issue I have had is the fuel returning bumping the float around hence you see the fuel level gauge move around a fair amount - to minimise it the return pipe has now been modified to disperse the fuel rather than a single stream.