josehf34

I want to replace my mechanical fuel pump because seems to be wear and old and maybe is sucking airm I was thinking about using an electrical one.

I've been having vapor lock problems while sitting in traffic for a long period of time (more than 45 minutes) the problem is this: I can see fuel in the fuel filter but when I restart the car the engine stalls and a lot of fuel vapor comes out of the carb air horn.

I was thinking about using this fuel pump: http://www.summitracing.com/int/part...01-1/overview/

But I don't know how can install a return line to keep fresh gas going to the carb. How can this be done? will be just to drill a new hole in the gas tank for the return line?

RacerHog

Put a good fuel pump on it.... That red pump will be to noisy....

Sample Shot.... http://www.jegs.com/i/Carter/180/M4862/10002/-1

Make sure all the hoses are good. And also make sure the tubing is all good as well...

Just my 2 cents

josehf34

mmm I was thinking about replace the mechanical pump with a carter mechanical pump but if I'm right with one of those the vapor lock problem can appear at any moment. Or Am I wrong?

RacerHog

Sure you can have vapor lock with ether pump......
Now you have to fix whats causing the Vapor lock...

Fuel Pumps don't cause vapor lock....

DDodger

.............Welll....................

REAR mount electric pumps DO help PREVENT vapor lock as opposed to a front mount mechanical.

Pay attention to line routing re: preventing

So far as a return, go to MyMopar and download the 72 and 73 shop manuals over there. Look in the fuel and the emissions sections to get an idea of how "they" routed the vapor return for the carbon can systems. THIS IS NOT THE SAME but it shows how the line was routed.

What I did: Punched a hole (not drilled) into the front face of the tank, this was an A body so might be "different" This creates a hole with rolled edges.

Then I plumbed my MIG CO2 bottle to the supply line after draining, and filled the tank with low pressure CO2, right out of the regulator on the CO2

Then just used a torch and silver brazed a short piece of tubing into the hole. I used 1/4" and WISH NOW I'd used 3/8

For return, use a wix 33040 or 33041 filter. This filter has a return port built in

Mr.4spd

Amen. I put the "blue" pump in my car last summer and the noise is making me crazy (and this is with rubber biscuits between the bracket, frame, and bolts!)

RacerHog

Get something like this.... Add a little rubber to the bracket and you will be good to go.... http://www.rockauto.com/catalog/more...jnid=40&jpid=2

RacerHog

Ya... I have found that if you cut an old tire and mount it between the frame and the pump..... It sure helps allot with Blue and Red Pumps....

I use quit a few of these pumps over the years.... Work well... But you still have to use a rubber insulator....
http://carterfuelsystems.com/fuelpumps/universal_fp.php

Rooty

Here's what I use on my '65 with a 383 with 410 H.P. Got it from Summit, mounts nicely on the passenger's side just ahead of the torque box. Quiet and efficient and been on there for 4 years. I run a fuel pressure regulator mounted to the firewall with a return port right on the regulator and it is set at 8 p.s.i. Forward and back from the tank I use 3/8 lines for a good volume of flow both ways. From the regulator to the carb I used 5/16 neoprene line. All's good. Carter's are really tried and tested pumps with low amp draw and would work great in your application.

http://www.summitracing.com/int/part...01hp/overview/

josehf34

The vapor lock only happens when I've been sitting in traffic for a long period of time (more than 45 minutes), after that the car starts stalling and everytime that happen a lot of fuel vapor comes out through the air horn. Is a bit strange because I can see fuel in the filter and in the carburetor bowl but the car stalls while idling and I have to put the throttle to the metal to get it running again

That carter pump looks like a good option, which regulator are you using?

Can the canister line that goes to the gas tank be used as the return line?

Rooty

Josehf34 here's how I did the return line. I bought two threaded bulkhead fittings and drilled two holes on the front flat of the tank nearest the bottom of the tank as I could. Reaching through the large hole with the sender removed, I mounted the bulkhead fittings (3/8). This allowed me to get a wrench inside the tank to hold the fitting's inner nut. Before inserting the fittings, I soldered two 3/8 copper pipes into the fittings - one for the pickup and one for return. Soft copper is best as it can be slightly bent inside the tank quite easily. The pickup side has a sock on the end of the pipe and then goes to the pump on the exterior using a threaded barbed fitting connected to neoprene fuel line. The return line curves inside the tank to send returned fuel around the perimeter of the tank to cool it. The bulkhead fitting "seal to tank wall" is done using flat fiber washers ( red in color ). You can also use a buna O-ring on the inside flange making sure the tightening nut for the fitting is on the outside. Again the return line connects to the bulkhead return fitting using a barbed MIA fitting that threads right into the bulkhead fitting. That's how I did mine and as you guessed I don't use the pickup tube on the sending unit at all. It's hard to find a sender with a tube much larger than 5/16. Now my fuel comes from the bottom of the tank ( 3/8 inch ) and returns at the bottom of the tank (3/8 inch) so there is no agitation, bubbling or internal fuming.