Fuel vaporizer

Claim 2

In an internal combustion engine having an air cleaner mounted on a carburetor having primary and secondary outlets, an intake manifold having primary and secondary inlets and an exhaust manifold, the improvement comprising a heat exchanger in heat exchange relationship with the exhaust system, a sealed first passageway flowably connected to said air cleaner before said air cleaner vents into the carburetor and a second sealed passageway flowably passing heated air from said heat exchanger through a port in the primary manifold inlet, said manifold having a web separating the primary and secondary inlets and extending partially into said manifold, said port in the primary manifold inlet located adjacent the primary carburetor outlet whereby the heated air mixes with the air/fuel mixture passing through the primary manifold inlet before said air/fuel mixture mixes with the air/fuel mixture passing through the secondary manifold inlet.

Claim 3

The internal combustion engine according to claim 1 wherein the carburetor has two primary and two secondary outlets and the intake manifold has two primary and two secondary inlets, the ports in said primary manifold inlets being substantially opposed.

Claim 4

The internal combustion engine according to claim 2 which further includes a check valve in said second sealed passageway, said check valve selectively opening and closing in response to carburetor vacuum.

Claim 5

The internal combustion engine according to claim 3 wherein the check valve remains closed when the vacuum pressure in the carburetor falls below about 12 in. Hg.

Claim 6

The internal combustion engine according to claim 4 wherein the check valve includes a ball and a valve seat, said ball adapted to be received in said valve seat when the valve is closed, said check valve further including a recess in a slotted plate, said ball adapted to be received in said slotted plate when the valve is open.

Claim 7

In an internal combustion engine having an air cleaner mounted on a carburetor having primary and secondary outlets, an intake manifold having primary and secondary inlets and an exhaust manifold, the improvement comprising a heat exchanger having an inner tube and an outer tube annularly spaced therefrom and sealed at its opposite ends to said inner tube, said inner tube interposed at its opposite ends in the exhaust system, said outer tube having an inlet and an outlet, a first tube having first and second ends sealed at said first end to a sidewall of the air cleaner and at said second end to the inlet in said outer tube, and a second tube having first and second ends sealed at said first end to the outlet in said outer tube and at said second end to a port in the primary manifold inlet, said manifold having a web separating the primary and secondary inlets and extending partially into said manifold, said port in the primary manifold inlet located adjacent the primary carburetor outlet whereby the heated air passing through the port mixes with the air/fuel mixture passing through the primary manifold inlet before said air/fuel mixture mixes with the air/fuel mixture passing through the secondary manifold inlet.

Claim 8

In an internal combustion engine having an air cleaner mounted on a carburetor having primary and secondary outlets, an intake manifold having primary and secondary inlets and an exhaust manifold, the improvement comprising a heat exchanger having an inner tube and an outer tube annularly spaced therefrom and sealed at its opposite ends to said inner tube, said inner tube interposed at its opposite ends in the exhaust system, said outer tube having an inlet and an outlet, a first tube having first and second ends sealed at said first end to a sidewall of the air cleaner and at said second end to the inlet in said outer tube, and a second tube having first and second ends sealed at said first end to the outlet in said outer tube and at said second end to a port in the primary manifold inlet, said manifold having a web separating the primary and secondary inlets and extending partially into said manifold, said port in the primary manifold inlet located adjacent the primary carburetor outlet whereby the heated air passing through the port mixes with the air/fuel mixture passing through the primary manifold inlet before said air/fuel mixture mixes with the air/fuel mixture passing through the secondary manifold inlet.

Claim 9

The internal combustion engine according to claim 6 which further includes a check valve interposed in said second tube between the outlet in said outer tube and the port in the primary manifold inlet, said check valve adapted to remain closed when the vacuum pressure in the carburetor falls below about 12 in. Hg.

Claim 10

The internal combustion engine according to claim 7 wherein the check valve includes a ball adapted to be received in a valve seat and held therein by gravity when the valve is closed, said ball adapted to be unseated by the vacuum pressure in the carburetor when the pressure is over about 15 in. Hg. when the valve is open, and said ball adapted to be received in a recess when the ball is unseated, said recess adapted to redirect the ball into its valve seat when the carburetor pressure falls.

Claim 11

The internal combustion engine according to claim 8 wherein the connections between the first tube and the air cleaner and the inlet in the outer tube and the connectors between the second tube and the outlet in the outer tube, the check valve and the port in the primary manifold inlet are by compression fittings.

Claim 12

The internal combustion engine according to claim 9 wherein said heat exchanger is interposed in an exhaust pipe portion of the exhaust system and wherein the inner tube of the heat exchanger has notched ends and an inside diameter large enough to slippingly receive exhaust pipe segments and be clamped thereto.