Thread: Plumbing fuel line

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Hi:
I have a question about plumbing the fuel line for my 47 chevy.
I bought the Summit Pumpkit2 and am about to install it.
My question is which side of the frame should I run it (driver or passenger)?

More details:
- I have a Holley 600 carb with gas inlet on driver's side.
- I have a Holley Red fuel pump that I was was going to mount on a bracket that I will attach to the rear sway bar.
- I have an in-line fuel filter which I was going to attach to the inner fender well.
- I already have the brake line running down the driver's side.
- I will be running the battery cable down the passenger side.
- The gas line attaches to the body - hopefully I have a good approximation of where it goes.

I see the easiest solution as running down the driver's side or else I will have to loop the fuel pump output back as shown in the picture.

Any suggestions would be greatly appreciated.
Thanks

PS: I have lots more pictures if anyone wants additional information.

I have both the brake line and fuel line running down the inside of the drivers side. Ford did it this way for years. I have no problem with it this way.

Clover47,
For my '33 I have the fuel inlet for the EFI on the driver's side, and the return fitting on the passnger side, both at the ends of the fuel rail. My first inclination was to run the lines down the drivers side, but like yours my brake lines were already on that side, and the area around the clutch and brake master cylinders was very constrained. I decided to run up the passenger side, cross over along the back side of the front crossmember, and turn up the driver's front corner of the block. On the return line I used a AN 180 fitting to route the line beside the distributor (Ford front mount). I tucked the pump above the gusset for the lower four link on the passenger side, offering some protection from road debris, then ran the two lines along the inside of the frame rail, tucking it inside the motor mount bracing. There's some pictures on post 68 in my build thread, not that it is rocket science.
http://www.clubhotrod.com/forums/sho...9&postcount=68

Most important thing is to mount a fuel filter BEFORE the fuel pump. Holley pumps do not like even a spec of dirt. Get one that has a replaceable cartridge (not one of those inline ones) and mount it right before the pump and after the tank.

One thing I have to ask. You mention you are mounting it to the sway bar. Doesn't that bar move? You really want to mount it to a crossmember or frame member. As for the rest, it doesn't matter which side you run it down, just keep it away from exhaust and moving parts. Leave enough room so the rear end doesn't hit it as it bounces up and down.

Don

1) I would mount the pump inlet at, or lower than the level of the gas tank. Think "self priming" for the fuel pump.

2) You didn't mention a regulator, you need one. Mount it near the carb.

3) Why all of the rubber hose? Stainless hose is still just "covered" rubber hose and will need replacing from time to time due to age and attack from the gas chemicals. IMO, you would be better off using hard tube. You can make it nice with stainless 3/8" tubing and AN tubing sleeves and tube nuts. It even polishes up nice on the buffer before you bend it. It will last and be cheaper than buying the AN fittings and stainless hose. But......you do need to borrow a quality (Imperial) tubing bender and a AN 37 degree flare tool if you go this route. You only need a hose that flexes between the engine and the frame, about 12".

4) One thing that I always do, is install a fuel shut off valve at the tank. The valve can shut off the fuel flow when you service the fuel filter or need to work on the fuel pump. Any good hardware store sells "ball valves" for natural gas that work fine with gasoline. They flow better than Earl's and only cost about $10. Time and money well spent.

I would attach the pump to any part of the frame ,not the sway bar. You want the pump NOT to be jiggled around. You also want the filter before the pump and lower like the guys here are saying. You want to mount the filter to a frame part like the pump. I also like to run the fuel lines on the outside of the frame rails> that way if you even have anything come off the moving drivetrain, it will not fly off and cut thru a fuel line.

Originally Posted by Itoldyouso

Most important thing is to mount a fuel filter BEFORE the fuel pump. Holley pumps do not like even a spec of dirt. Get one that has a replaceable cartridge (not one of those inline ones) and mount it right before the pump and after the tank.
Don

Don,
This is one that you and I disagree on. In support of my analysis of the system hydraulics, Edelbrock instructs that it is important for the filter to be AFTER the pump. From their ProFlow XT instructions, Fuel System Installation pages:
7. Mount the fuel pump between the tank and the fuel filter as low and as close to the fuel tank as possible. The pump is directional. Electrical connectors should face the front of vehicle. The fuel pump needs to be at or below the bottom of the fuel tank.
8. Mount the fuel filter between the fuel pump and the engine.
This is their brochure for the whole picture - http://www.edelbrock.com/automotive_.../3000/3520.pdf
As for the hydraulics, the pump is designed for a positive suction head and is not designed to "pick up" the fuel. By installing the filter in the suction line you are imposing pressure drop in that line that is equivalent to raising the pump several inches. This means that as your tank level falls you will reach a point where the pump is operating off design, and as your filter ages you may well be negative on pump suction witih a full tank. Cleanliness is critical, and if you read their instructions they say to have an old tank "professionally cleaned".

For me, I rely on the inlet sock filter in the tank to protect the pump, and I install the filter downstream of the pump where it eats away a small amount of pump head (pressure) as it ages, but keeps the pump primed at all times leading to longer pump life. I respect the alternate position on this, and I know that there are many who prefer to filter the pump inlet but the physics don't work for me.

My thoughts - some of which are repeats from above. Which side you use to run the fuel line doesn't matter. Use the easiest route. Mount the fuel pump to the frame, not to a sway bar, and make sure you use some rubber stand-offs to isolate for sound. Those Holley fuel pumps are noisy with a capital N. Steel line is better and cheaper than braided hose, and will last a lot longer.

Also, make sure that your Holley pump is accessable. You may have to change it out. I quit buying them because I had too many fail. I have switched to Edelbrock Quiet-Flo pumps. They are quieter and don't run as hot.

I did install a large, can-type filter right at the gas tank outlet, well in front of the pump. As Roger says, this may not be a good idea, but I have noticed no ill effects on pressure or fuel flow, and I monitor my fuel pressure at the carb.

sorry to argue but the Holley Red pump doesn't use a regulator, your thinking of the Blue pump.

I agree about the hard line, just use a small piece of rubber each end to cope with movement.

I've always mounted the filters after the pump, they can handle particles and i've never had a problem.

I've also switched these days to Carter pumps as they are quieter.

Originally Posted by John Palmer

1) I would mount the pump inlet at, or lower than the level of the gas tank. Think "self priming" for the fuel pump.

2) You didn't mention a regulator, you need one. Mount it near the carb.

3) Why all of the rubber hose? Stainless hose is still just "covered" rubber hose and will need replacing from time to time due to age and attack from the gas chemicals. IMO, you would be better off using hard tube. You can make it nice with stainless 3/8" tubing and AN tubing sleeves and tube nuts. It even polishes up nice on the buffer before you bend it. It will last and be cheaper than buying the AN fittings and stainless hose. But......you do need to borrow a quality (Imperial) tubing bender and a AN 37 degree flare tool if you go this route. You only need a hose that flexes between the engine and the frame, about 12".

4) One thing that I always do, is install a fuel shut off valve at the tank. The valve can shut off the fuel flow when you service the fuel filter or need to work on the fuel pump. Any good hardware store sells "ball valves" for natural gas that work fine with gasoline. They flow better than Earl's and only cost about $10. Time and money well spent.

Roger and Steve, as much as I respect your opinions on not mounting a filter before the pump, here is info straight off of Holley's installation instruction sheet:
____________________________________________________________________________
NOTE: To ensure pump life and flow efficiency, a quality fuel filter, such as Holley P/N 162-515 must be installed between the tank and each pump inlet. The filter should be supported in such a manner that it does not hang from the fuel lines.
4. Connect the fuel line from the tank to the fuel filter and then to the inlet port of the pump. Connect the carburetor delivery line to the outlet port of the pump and to the regulator (for the 12-150) located near the carburetor inlet. See Figure 1. The fuel pump inlet and outlet ports take a 3/8” NPT fitting, therefore a 3/8” or larger fuel line is recommended.
____________________________________________________________________________

I've pretty much always used Holley electric pumps in cars, even some daily drivers that saw lots of miles, and I have ALWAYS used a filter before the pump. Holley pumps will stick open internally with even a spec of dirt ( I had some fiberglass dust in my 27 tank that kept getting even through the filter, the specs were that small, but they would jam the check valve open and kill the pressure)

This is also the way we always rigged a boat engine, be it outboard or inboard, with the filter before the pump. Think of every outboard engine you have seen, the water separating filter is mounted between the tank and the motor, and the pump is on the motor. Those pumps are wimpy compared to a Holley and they draw just fine through the filters.

And here is what Carter says on their instruction sheets:

_________________________________________________________________________________

The universal fuel pump should be mounted below the
fuel tank, as all pumps do not have equal lift capabilities.
Also, the pump must be mounted below the carburetor
to avoid possible vapor lock conditions occurring.
Under no circumstances should the pump be mounted
in the trunk, inside the vehicle, or in the engine
compartment; personal injury could occur in the
event of a fuel line rupture.
NOTE: Not al universal electric fuel pumps are
capable of a pul-through arangement with
an existing mechanical fuel pump system. Check
information on al universal electric pumps.
PRESSURE SAFETY SWITCH A-68301
INSTALLATION INSTRUCTIONS
A pressure switch should always be used in conjunction
with the Universal In-Line Electric Fuel Pump. ICC Motor
Carrier Safely Regulations stipulate that the fuel pump
must not continue to operate after the engine stops. The
Safety Interlock Circuit stops the electric fuel pump when
the engine stops even though the ignition switch is not
turned “Off.” The pressure switch is a single-pole, doublethrow,
diaphragm-actuated switch. Terminals P (Pump)
and S (Start) are normally closed; terminals P (Pump) and
I (Ignition) are normally open. This allows the fuel pump
to operate and fill the carburetor while the engine is
cranking. When oil pressure exists (2 to 4-1/2 psi), the
P and S terminals are opened, and the P and I are
closed. The diaphragm is treated to withstand pressure
up to 150 psi.
If the oil pressure drops below 2 psi, the connection
between P and I opens and the fuel pump stops. This
also protects the engine from severe damage if an oil
line is broken or the oil level in the crankcase becomes
extremely low.
Full battery voltage must be available to the pump when
the ignition switch is in the start or run position. Do not
connect to the ignition coil, as a ballast resistor may be
built into the wire.
Safety Interlock System
The pressure switch should be installed
at a convenient location in the engine oil
pressure system. In some instances, it may
be necessary to install a “T” fitting below
the existing oil gauge sender or
dashlight unit.
Wires should be 18-gauge insulated,
or heavier, routed so as to protect
them from exhaust heat, and
anchored securely at frequent
intervals to prevent chafing.

(Here is the line that is of interest to us in this discussion)

Always mount a good quality fuel filter on the inlet side
of the pump. Failure to do so will void the warranty.
Do not mount the pump near exhaust system
components, as heat contributes to vapor lock.
____________________________________________________________________________


This is just the way I have been taught to do the pump/filter installation, both in my car hobby and my marine profession.

Don

Originally Posted by Itoldyouso

Roger and Steve, as much as I respect your opinions on not mounting a filter before the pump, here is info straight off of Holley's installation instruction sheet.....(specifics removed for space)
This is just the way I have been taught to do the pump/filter installation, both in my car hobby and my marine profession.
Don

Don,
The respect on opinions is mutual, and you obviously have followed the recommendations of the equipment suppliers in your approach as I did in mine. I suppose that to maintain warranties, etc, it is best to consider the OEM instructions and then do what we believe to be best for our specific installations. Like Jack stated, monitoring the pressure at the carb or fuel rail is a good idea, with an occasional cruise rpm check as filters age.

Thanks for taking time to include the Holley and Carter references. I really appreciate this type of dialog as it makes me think about why I've done something a certain way, and learning is never a bad thing.

Ditto. The old guys always know best

Originally Posted by rspears

Don,
The respect on opinions is mutual, and you obviously have followed the recommendations of the equipment suppliers in your approach as I did in mine. I suppose that to maintain warranties, etc, it is best to consider the OEM instructions and then do what we believe to be best for our specific installations. Like Jack stated, monitoring the pressure at the carb or fuel rail is a good idea, with an occasional cruise rpm check as filters age.

Thanks for taking time to include the Holley and Carter references. I really appreciate this type of dialog as it makes me think about why I've done something a certain way, and learning is never a bad thing.

If you draw fuel out of the bottom of the tank/cell through a sump or otherwise, the filter absolutely goes in front of the pump. If you draw through a stock pickup with a sock, it obviously isn't going to be as critical.

Old guys, huh Steve. Can't wait till you come back and I take you to that excellent English Pub again. Well, I do admit I like the Seniors Discount at I Hop every Tuesday.

Don

Originally Posted by itoldyouso

old guys, huh steve. Can't wait till you come back and i take you to that excellent english pub again. :lol::lol: Well, i do admit i like the seniors discount at i hop every tuesday. :d

don