Post by charlie on May 23, 2016 19:30:24 GMT 12
Hi there. I would like clarification please regards fitment of a surge tank and fuel pump.
Let's assume for a moment there is no boot. That leaves only the cabin and the engine compartment as candidates for surge tank and fuel pump location.
This might be true of station wagons or a mid-engined car with no boot (a heavily modified MR2 perhaps).
Looking at the HCTM chapter 10 regards fuel systems:
lvvta.org.nz/documents/suplementary_information/HCTM_SAMPLE_Chapter-10_Fuel%20Systems.pdf
Here's my understanding of the rules. Please clarify or correct me if needs be, thanks.
Regards placement of a surge tank and pump in the cabin:
10.2.1
A fuel tank and its related fuel system components may be located within the boot or passenger compartment of a low volume vehicle, provided that the requirements specified in 10.4 and 10.5 are met.
Looking at those sections:
10.4.1
A low volume vehicle that has a fuel tank located on top of the floor surface, must have the floor and surrounding area in which the fuel tank is located, designed in such a way that any fuel, in the event of a fuel tank leak or rupture: (see Diagrams 10.1 & 10.2)
(a) cannot come into contact with the vehicle’s battery or battery leads; and
(b) will escape to the outside of the vehicle, without draining onto either:
(i) any part of the vehicle’s exhaust system; or
(ii) any part of the vehicle’s electrical system.
Q: So the surge tank needs to sit in a section of the floor designed to act like a funnel and that section needs a drain hole through the floor to the ground. Correct?
Q: Do the words "floor and surrounding area" mean that a surge tank fitted in the cabin needs to be fully enclosed in some kind of box?
Diagrams 10.1 and 10.2 both show a fuel and vapour proof bulkhead.
Yet section 10.4.2 seems to suggest that a surge tank does not need to be isolated from the passenger compartment as it has no filler cap and functions as a sealed unit:
10.4.2
A low volume vehicle that has a fuel tank located on top of the floor surface, and can be filled from inside the trunk or passenger compartment, must have an isolating panel made from a fuel- resistant material to prevent fuel, or fuel vapour, from entering the passenger compartment.
So my understanding would be as follows:
If the filler cap is merely the OEM one on the main fuel tank and the surge tank is filled only by way of fuel lines then 10.4.2 means I am not legally required to fully enclose (isolate) a surge tank if it's in the cabin, because it cannot "be filled from inside the trunk or passenger compartment".
Q: Is this correct?
Q: Legalities aside, if I were to enclose it in some kind of box as an added safety measure (this would seem sensible in case of a leak etc) are you able to point me at a relevant specification please? Or does the interpretation of "fuel resistant and vapour-proof bulkhead" (diagrams 10.1 and 1.2) rest with the certifier?
Section 10.5 deals with venting, and is therefore irrelevant where a surge tank is concerned as far as I can tell, because there is no venting from the surge tank. Only a return line back to the main tank.
Q: In a nutshell, if I were to mount a surge tank and pump in the cabin, do they need to be fully enclosed in a box to isolate them from the cabin? As far as I can tell by reading the regs, the answer would seem to be "legally, no.. but it would be a sensible move".
Please advise.
OK, what about mounting a surge tank in the engine bay?
I return to section 10.4.1
10.4.1
A low volume vehicle that has a fuel tank located on top of the floor surface, must have the floor and surrounding area in which the fuel tank is located, designed in such a way that any fuel, in the event of a fuel tank leak or rupture: (see Diagrams 10.1 & 10.2)
(a) cannot come into contact with the vehicle’s battery or battery leads; and
(b) will escape to the outside of the vehicle, without draining onto either:
(i) any part of the vehicle’s exhaust system; or
(ii) any part of the vehicle’s electrical system.
Q: The engine bay has no floor. A surge tank mounted in the engine bay is therefore not "located on top of the floor surface". Is this correct?
I ask, in case I have misunderstood the definition of "floor surface" or something. For example it doesn't refer to some imaginary line drawn through the car from end to end, does it?
Q: Does this mean it is OK to fit a surge tank and fuel pump in the engine bay? No isolating panel required? For example if the surge tank and pump are located away from the exhaust and not above it or any electrics, is the engine bay legally an ok place to fit them? Please confirm.
I have one last question regards the hose and fittings in the cabin, if I were to fit a surge tank and pump there.
10.2.1
A fuel tank and its related fuel system components may be located within the boot or passenger compartment of a low volume vehicle, provided that the requirements specified in 10.4 and 10.5 are met.
This states it's ok to fit both a surge tank and pump in the cabin as long as the requirements of sections 10.4 and 10.5 are met. But I am left with a question regards the fuel lines required to do so. Namely, the line from the surge tank to the pump. 10.8.5 (d) seems a bit confusing:
10.8.5
Rigid fuel pipe or flexible purpose-designed automotive braided stainless steel covered hose may be located within the passenger compartment of a low volume vehicle, provided that:
(a) the hose cannot come in contact with either the driver or other vehicle occupants during normal vehicle operation; and
(b) the pipe or hose is secured firmly against the floor at intervals of no more than 300 mm (12”); and
(c) the hose can be readily inspected for wear or damage; and
(d) there are no pipe or hose joins or connections inside the passenger compartment, other than for purpose-designed bulkhead fittings.
Q: Can I fit a surge tank & fuel pump in the cabin, with a line in the cabin going from surge tank to pump as long as it meets the requirements of 10.8.5 (a) (b) and (c), and with the other lines going directly to bulkhead fittings like this one: www.aeroflowperformance.com/fittings/bulkhead-fittings/bulkhead-an/af832-10
Thank you in advance for your patience in answering these questions as fully and precisely as you can. Your help is very much appreciated and is sure to helps others in the future.
Let's assume for a moment there is no boot. That leaves only the cabin and the engine compartment as candidates for surge tank and fuel pump location.
This might be true of station wagons or a mid-engined car with no boot (a heavily modified MR2 perhaps).
Looking at the HCTM chapter 10 regards fuel systems:
lvvta.org.nz/documents/suplementary_information/HCTM_SAMPLE_Chapter-10_Fuel%20Systems.pdf
Here's my understanding of the rules. Please clarify or correct me if needs be, thanks.
Regards placement of a surge tank and pump in the cabin:
10.2.1
A fuel tank and its related fuel system components may be located within the boot or passenger compartment of a low volume vehicle, provided that the requirements specified in 10.4 and 10.5 are met.
Looking at those sections:
10.4.1
A low volume vehicle that has a fuel tank located on top of the floor surface, must have the floor and surrounding area in which the fuel tank is located, designed in such a way that any fuel, in the event of a fuel tank leak or rupture: (see Diagrams 10.1 & 10.2)
(a) cannot come into contact with the vehicle’s battery or battery leads; and
(b) will escape to the outside of the vehicle, without draining onto either:
(i) any part of the vehicle’s exhaust system; or
(ii) any part of the vehicle’s electrical system.
Q: So the surge tank needs to sit in a section of the floor designed to act like a funnel and that section needs a drain hole through the floor to the ground. Correct?
Q: Do the words "floor and surrounding area" mean that a surge tank fitted in the cabin needs to be fully enclosed in some kind of box?
Diagrams 10.1 and 10.2 both show a fuel and vapour proof bulkhead.
Yet section 10.4.2 seems to suggest that a surge tank does not need to be isolated from the passenger compartment as it has no filler cap and functions as a sealed unit:
10.4.2
A low volume vehicle that has a fuel tank located on top of the floor surface, and can be filled from inside the trunk or passenger compartment, must have an isolating panel made from a fuel- resistant material to prevent fuel, or fuel vapour, from entering the passenger compartment.
So my understanding would be as follows:
If the filler cap is merely the OEM one on the main fuel tank and the surge tank is filled only by way of fuel lines then 10.4.2 means I am not legally required to fully enclose (isolate) a surge tank if it's in the cabin, because it cannot "be filled from inside the trunk or passenger compartment".
Q: Is this correct?
Q: Legalities aside, if I were to enclose it in some kind of box as an added safety measure (this would seem sensible in case of a leak etc) are you able to point me at a relevant specification please? Or does the interpretation of "fuel resistant and vapour-proof bulkhead" (diagrams 10.1 and 1.2) rest with the certifier?
Section 10.5 deals with venting, and is therefore irrelevant where a surge tank is concerned as far as I can tell, because there is no venting from the surge tank. Only a return line back to the main tank.
Q: In a nutshell, if I were to mount a surge tank and pump in the cabin, do they need to be fully enclosed in a box to isolate them from the cabin? As far as I can tell by reading the regs, the answer would seem to be "legally, no.. but it would be a sensible move".
Please advise.
OK, what about mounting a surge tank in the engine bay?
I return to section 10.4.1
10.4.1
A low volume vehicle that has a fuel tank located on top of the floor surface, must have the floor and surrounding area in which the fuel tank is located, designed in such a way that any fuel, in the event of a fuel tank leak or rupture: (see Diagrams 10.1 & 10.2)
(a) cannot come into contact with the vehicle’s battery or battery leads; and
(b) will escape to the outside of the vehicle, without draining onto either:
(i) any part of the vehicle’s exhaust system; or
(ii) any part of the vehicle’s electrical system.
Q: The engine bay has no floor. A surge tank mounted in the engine bay is therefore not "located on top of the floor surface". Is this correct?
I ask, in case I have misunderstood the definition of "floor surface" or something. For example it doesn't refer to some imaginary line drawn through the car from end to end, does it?
Q: Does this mean it is OK to fit a surge tank and fuel pump in the engine bay? No isolating panel required? For example if the surge tank and pump are located away from the exhaust and not above it or any electrics, is the engine bay legally an ok place to fit them? Please confirm.
I have one last question regards the hose and fittings in the cabin, if I were to fit a surge tank and pump there.
10.2.1
A fuel tank and its related fuel system components may be located within the boot or passenger compartment of a low volume vehicle, provided that the requirements specified in 10.4 and 10.5 are met.
This states it's ok to fit both a surge tank and pump in the cabin as long as the requirements of sections 10.4 and 10.5 are met. But I am left with a question regards the fuel lines required to do so. Namely, the line from the surge tank to the pump. 10.8.5 (d) seems a bit confusing:
10.8.5
Rigid fuel pipe or flexible purpose-designed automotive braided stainless steel covered hose may be located within the passenger compartment of a low volume vehicle, provided that:
(a) the hose cannot come in contact with either the driver or other vehicle occupants during normal vehicle operation; and
(b) the pipe or hose is secured firmly against the floor at intervals of no more than 300 mm (12”); and
(c) the hose can be readily inspected for wear or damage; and
(d) there are no pipe or hose joins or connections inside the passenger compartment, other than for purpose-designed bulkhead fittings.
Q: Can I fit a surge tank & fuel pump in the cabin, with a line in the cabin going from surge tank to pump as long as it meets the requirements of 10.8.5 (a) (b) and (c), and with the other lines going directly to bulkhead fittings like this one: www.aeroflowperformance.com/fittings/bulkhead-fittings/bulkhead-an/af832-10
Thank you in advance for your patience in answering these questions as fully and precisely as you can. Your help is very much appreciated and is sure to helps others in the future.