Mechanical Pump with Return Line- input/pictures/etc.

-
SLOPAR72

SLOPAR72

Well-Known Member
Joined
Jan 5, 2016
Messages
3,543
Reaction score
3,619
Location
Richmond, VA.
I have my new tank installed with 3/8" lines run for feed and return Sending unit with additional nipple for return.) For now I will be keeping the Mechanical Pump with Carb and if someone else has done this please chime in with where you sent fuel back to the tank in reference to how far past the Fuel Pump on the feed line. I am running a Carter Pump and will not be needing a Regulator. No Electric Pump also. Pictures would be great also.

I looked through the search and only found Electric Pump setups. But I am not known for being savvy on the net at times lol....

Thanks,
JW
 
Confused about why you would run a return with the Carter mechanical pump. No excess pressure to bleed off just connect to carb inlet and enjoy.
 
v8fish said:
Confused about why you would run a return with the Carter mechanical pump. No excess pressure to bleed off just connect to carb inlet and enjoy.
Click to expand...

Because even with a mechanical pump, it will run much better and any chance of vapor lock will be gone. The whole purpose of a return system is to assure cool fuel to the engine. Without a return, the fuel will simply sit in the lines waiting to be burned. With crappy ethanol pump gas, that's not a good recipe for a happy engine in traffic in hot summer months.

You can do the return a couple of ways. You can get a filter with an orificed return nipple in it, or you can simply run a return regulator like the Mr Gasket 2015. My personal preference is to get the return point as close to the carburetor as possible. You can actually place the regulator after the carburetor and it will work just the same. It does not matter where in the system it is, it will still regulate the fuel pressure.
 
Vapor loc in VA? what's your elevation there? and typical summer temps?
Do you experience it with all kinds of fuel?
I tell you what, I've never had a problem with that here in MB. Maybe cuz I run an AirGap and the carb gets fresh cold air from above the hoodline. I also run a solid line from the pump to the dual feed, except for a short jumper at the dual-feed. There is another very short jumper from the supply line to the pump,down by the framerail. And another back at the tank.All clamps are factory flat bandclamps, except the jumper at the dual-feed,where I have gearclamps two to a side with the screws staggered 180*. IMO,The factory had the right idea when they used those little flat spring clamps.
I say this because this works here in Manitoba, where the elevation is a little under 1000 ft, the summertime temps rarely exceed 95*, but can run there or near there for an entire month, with the nighttime temps about 10* cooler. and I burn 87E10 exclusively.
So what's the point?
Well I have found that mechanical fuelpumps suck air through single gearclamp connections more than one might think, and yet that same connection will not leak fuel.The jumper at the top of the tank is a "favorite".
 
Last edited:
RustyRatRod said:
Because even with a mechanical pump, it will run much better and any chance of vapor lock will be gone. The whole purpose of a return system is to assure cool fuel to the engine. Without a return, the fuel will simply sit in the lines waiting to be burned. With crappy ethanol pump gas, that's not a good recipe for a happy engine in traffic in hot summer months.

You can do the return a couple of ways. You can get a filter with an orificed return nipple in it, or you can simply run a return regulator like the Mr Gasket 2015. My personal preference is to get the return point as close to the carburetor as possible. You can actually place the regulator after the carburetor and it will work just the same. It does not matter where in the system it is, it will still regulate the fuel pressure.
Click to expand...

We are on the same page and thanks for reassuring me this is a step in the right direction. I am going to regulate it on the return side (think EFI) and get it with 6" of the Carburetor. I am thinking it won't take a strong return flow to help with the Vapor Locking. It works great with Electric Pumps but that may happen down the road with an Intank.

Thanks,
JW
 
I totally agree with Rusty on this.:D
For what it's worth I ran my fuel lines up the firewall right next to the inner fender and then over to the carb.
It's also insulated, and I have an electric pump back at the tank with 3/8 feed and return with my T for the return right at the carb.
That exposed steel line all covered up with hot stuff from the pump to the carb was a dumb idea.
 
TrailBeast said:
I totally agree with Rusty on this.:D
For what it's worth I ran my fuel lines up the firewall right next to the inner fender and then over to the carb.
It's also insulated.
That exposed steel line all covered up with hot stuff from the pump to the carb was a dumb idea.
Click to expand...

My dad did something similar with the line and routed it on the edges of the Inner Fenders. It looked good short of using Rubber line for a few of the bends. I will use my Nitrous wielding tubing skills and fab one up without any rubber lol...

JW
 
OK so I checked All-knowing Google, and he says richmond VA is about 166ft above sea-level and the summer time high temp is 69.5.
What I want to know is how on earth you can be cooking your gas under these conditions.
I run my cooling system at 205*F, so my 7-blade fan is pounding heat under my hood, and my aluminum heads are gushing heat under the hood, and my uncoated TTIs are also pouring heat. And my fuel lines are un-insulated, and my carb is bolted to the intake with nothing more than the 1/4" or so standard paper spacer,and this thing has done 4 back to back 1/8mile runs with about 10/15 minutes of idle time in the line-up, on a near90* day, and it went 93mph on the last run. After the last run it was back to the pits,hang the exhaust system, put the street tires back on,reload, and off to the parking lot we go. Some 3 hours later, my son and I had our fill of that and we jump into the car and off we go.
At no time was there a hint of a fuel issue.
And my pump dead-heads at the carb.
And I run 87E10 (right now,yesterday at $0.88 a liter,Cunuk)
So tell me AJ, what's yur point? Ummmmmm, oh yeah; are you having an issue?, or are you attempting to avoid an issue? Or at the risc of sounding like an aZZ,do you just have nothing better to do, or spend yer money on? Ino,Ino, that's harsh. Well only if it's applicable. I just can't understand vaporloc at 69.5*F and 166ft.elevation.Or even, as in my case; near90*F and 880ft.
 
Last edited:
AJ/FormS said:
OK so I checked All-knowing Google, and he says richmond VA is about 166ft above sea-level and the summer time high temp is 69.5.
What I want to know is how on earth you can be cooking your gas under these conditions.
I run my cooling system at 205*F, so my 7-blade fan is pounding heat under my hood, and my aluminum heads are gushing heat under the hood, and my uncoated TTIs are also pouring heat. And my fuel lines are un-insulated, and my carb is bolted to the intake with nothing more than the 1/4" or so standard paper spacer,and this thing has done 4 back to back 1/8mile runs with about 10/15 minutes of idle time in the line-up, on a near90* day, and it went 93mph on the last run. After the last run it was back to the pits,hang the exhaust system, put the street tires back on,reload, and off to the parking lot we go. Some 3 hours later, my son and I had our fill of that and we jump into the car and off we go.
At no time was there a hint of a fuel issue.
And my pump dead-heads at the carb.
And I run 87E10 (right now,yesterday at $0.88 a liter,Cunuk)
So tell me AJ, what's yur point? Ummmmmm, oh yeah; are you having an issue?, or are you attempting to avoid an issue? Or at the risc of sounding like an aZZ,do you just have nothing better to do, or spend yer money on? Ino,Ino, that's harsh. Well only if it's applicable. I just can't understand vaporloc at 69.5*F and 166ft.elevation.Or even, as in my case; near90*F and 880ft.
Click to expand...

Well to be honest I will be the coolest kid on the block with trickery metal lines running amuck throughout the car. I might even use a blingy Hobbs Switch with a flashy Led light to make sure the fuel is flowing correctly.......

You need to get out of the Igloo and drag that car to Richmond, Va. in the summer and you will find out....

In all seriousness, the idea is to prevent any Vaporlock based on what I have seen people and myself deal with in the area. As for the expense, I am single so plenty of money to throw around lol....

JW
 
Dang that Google lieing scumbag miss-information spreader.

But just FYI; the igloos all do eventually melt, just before the new ones go up,lol.It's a continuous cycle. When we see all the fresh white, we know summer is over. For a little while tho it gets messy, what with the furniture out on the lawn and everyone sleeping under the stars and everything.
 
AJ/FormS said:
Dang that Google lieing scumbag miss-information spreader.

But just FYI; the igloos all do eventually melt, just before the new ones go up,lol.It's a continuous cycle. When we see all the fresh white, we know summer is over. For a little while tho it gets messy, what with the furniture out on the lawn and everyone sleeping under the stars and everything.
Click to expand...

Lol.... I do like me a good snow storm....

JW
 
AJ/FormS said:
Well IIRC you guys got a lot of it last winter. A lot more than we did,that's for sure. We barely accumulated enough to keep the ground covered.
Click to expand...

Yes we did. Garage roof collapsed and things went bad for the Bassboat. Had my 340 car started the weekend before that storm it would have been sitting where the boat was..... And that would not have turned out good.....

JW
 
This is what I did last summer. I've been fighting issues since installing the Edelbrock heads 3 years ago. I took two barbed fittings, one male and one female. I filled the male fitting with silver solder and then drilled a .040" hole in the solder and screwed the two halves together. I then attached everything in the photos to a 1/4" return line that runs back to the tank. I haven't had any issues since. I am going to eliminate the fuel pressure regulator because I don't need it any longer. The car holds a consistent 7lbs with the Carter mechanical strip pump. I am also going to bend up another hard line from my fittings to the return line running back to the firewall so I can get to the valve cover if needed.
new resize.jpg
new resize 2.jpg
new resize 3.jpg
 
RCK850 said:
This is what I did last summer. I've been fighting issues since installing the Edelbrock heads 3 years ago. I took two barbed fittings, one male and one female. I filled the male fitting with silver solder and then drilled a .040" hole in the solder and screwed the two halves together. I then attached everything in the photos to a 1/4" return line that runs back to the tank. I haven't had any issues since. I am going to eliminate the fuel pressure regulator because I don't need it any longer. The car holds a consistent 7lbs with the Carter mechanical strip pump. I am also going to bend up another hard line from my fittings to the return line running back to the firewall so I can get to the valve cover if needed.
View attachment 1715001997 View attachment 1715001999 View attachment 1715002000
Click to expand...

Finally someone who has photos of doing this lol.... You have done exactly what I am doing. I like the Silver Solder idea and will use that method. When I get the car out of the garage this weekend I will take pictures of how I did mine but we are pretty close to the same idea though I have run 3/8" steel line back to the tank. I also do not intend on running a regulator and will be install a Carter HV pump once I get a few miles on the car. It has sat for a long time and wanted to make sure everything is sorted out before changing up the fuel system. I am really liking the look of Big Blocks in the A Body's way more than I use to....

Thanks,
JW
 
You must log in or register to reply here.
-

Back
Top