Chassis Construction
Fuel, Oil and Radiator Plumbing

Page 15
Go To Page:  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17
Back to Contents


We have five main areas of "plumbing" to contend with: power steering, brakes and clutch, fuel, oil and engine cooling. 

The power steering plumbing has been partially complete for months. The control valve to steering rack lines are complete and installed; the lines between the control valve and pump were installed on the control valve and left long for us to complete once the engine installation was complete.  We're now at that point.

We completed the brake and clutch plumbing several months ago when we installed the pedal assembly.  We recently filled both those systems with brake fluid and bled them until the pedals were firm and they seemed to operate correctly.  We've subsequently decided to change the clutch master cylinder to a slightly smaller bore in order to "lighten" the clutch a bit.  The brakes seem fine at the moment but we have a brake pressure gage on order to confirm that the front and rear brake pressures are in the "ballpark" with moderate pedal pressure.  We can change those master cylinder sizes if needed also.

Our fuel system is fairly simple; we come out of the fuel cell to a "pre-filter", into the fuel pump, out of the fuel pump to a fine "post-filter" then to the fuel rails.  To regulate fuel pressure, we come out of the fuel rails to an "Aeromotive" fuel pressure regulator that returns excess fuel to the fuel cell.

Our "dry sump" oil system is more complicated than the "wet sump" system found in most autos.  Our engine doesn't retain any oil in the "sump"; oil is stored in an external oil tank that collects oil "scavenged" from the engine.  That tank supplies oil to an external oil pump that is actually two pumps in one; a "scavenge" pump that recovers oil from the engine after it has done it's job and a "pressure" pump that delivers oil to the oil filter then back to the engine under pressure.  This "dry sump" system will ensure a constant supply of oil to the engine under all conditions.

Engine cooling is accomplished by a large radiator with electric fans located just above our fuel cell.  The radiator is supplied with "ram air" via a duct between the roof and roof rack when the car is in motion and the fans when the car is stationary.  To compliment the radiator, we have a "surge tank" in addition to an "overflow tank".  The surge tank serves to help eliminate trapped air in the cooling system while keeping the coolant level full.  The overflow tank provides a place for excess coolant to be retained when necessary.  It's a fairly simple cooling system but will require a little bit of fabrication to make everything work well together.  The plumbing will consist of 1 1/2" aluminum and silicone tubing with a few smaller fittings required for connecting the surge tank.


Some of the fittings and hoses we'll use to plumb the fuel and oil systems
Rather than order custom made hose assemblies for all the different connections we need, we chose to order the necessary fittings and bulk hose so that we can fabricate our own custom hoses.


Oil pump to oil filter adapter hose assembly
We installed a "fire sleeve" on this particular hose for abrasion resistance more than fire resistance.


Fuel pressure regulator
Filtered fuel is supplied directly to the fuel rails from the fuel pump; this device, also connected to the fuel rails, bleeds off excess fuel and returns it to the fuel cell, regulating fuel pressure as a result.  This assures a constant, stable supply of clean fuel at the correct pressure while reducing or eliminating the threat of "vapor lock".


Dry sump system plumbing complete
All the hose assemblies for the oiling system are now complete and temporarily attached.  We still need to flush and inspect each one, then final install them.  Given the proximity to the engine and exhaust system, we elected to "fire sleeve" all the oil hose assemblies.


Trevor fabricating cooling system hard tubes
Trevor started with 8' of straight aluminum tubing and a few pieces of bent aluminum and silicone tubing.  He then pieced it all together to fabricate the two main coolant tubes between the engine and radiator


Coolant tubes and thermostat housing leak/pressure tested
Trevor had to modify the thermostat housing in order to clear the exhaust headers. Once everything was welded, he leak checked each tube and made small weld repairs as necessary.  He then etched (you can see the powdery residue on the tubes) and "Alodine" treated all the aluminum tubes for corrosion protection.


Engine coolant inlet line fitted
This is the line from the radiator that feeds the engine's coolant pump.  It'll be supported/secured in several locations to ensure there are no chaffing, bending or vibration issues.


Inlet line connected to the thermostat housing
The thermostat housing needed to be modified a bit to clear the exhaust manifold with plenty of room.  Trevor cut the stock housing then added sections of bent aluminum tube to create the shape we needed.


Radiator return line fitted
This tube returns hot coolant from the engine to the radiator.


Radiator return line engine connection
We chose to run the hard tubes along the bumper tubes as much as possible.  That gives us an easy solution for securing the tubes, keeps them somewhat protected and keeps them situated as "compactly" as possible.  "T bolt" clamps to come next.


"T bolt" clamps installed
We had several different options for securing the cooling hoses to the radiator and engine; "crimp" clamps, "hose" clamps and "T bolt" clamps.  We want the system to be serviceable in the field so "crimp" clamps are out of consideration.  "Hose" clamps are easy but they tear up hoses and look cheap.  "T bolt" clamps are the most secure option and they don't tear up the hoses - that's why we chose them.  The only down-side is that they're expensive.  Fortunately, we only needed a total of eight...



Page 15
Go To Page:  1  2  3  4  5  6  7  8  9  10  11   12  13  14  15  16  17
Back to Contents