Snowmobile heat exchanger assembly

1. A snowmobile comprising:

a frame having a tunnel;

a motor supported by the frame;

at least one ski connected to the frame;

a rear suspension assembly connected to the tunnel;

a drive track disposed around the rear suspension assembly and at least in part below the tunnel, the drive track being operatively connected to the motor; and

drive sprockets operatively connecting the motor to the drive track,

at least a portion of the tunnel being formed by a heat exchanger assembly, the heat exchanger assembly comprising:

a front portion;

a middle portion rearward of the front portion;

a rear portion rearward of the middle portion, at least one of the front and rear portions being curved from the middle portion, the at least one of the front and rear portions extending below the middle portion;

a top part; and

a bottom part disposed below the top part and being joined to the top part, the bottom part defining at least one recess,

the top and bottom parts defining therebetween a passage formed in part by the at least one recess,

the passage having an inlet and an outlet,

a first portion of the passage defined by the at least one recess extending longitudinally;

the drive track comprising:

a plurality of lugs extending from an outer surface of the drive track; and

a plurality of studs connected to and extending from the plurality of lugs,

portions of the plurality of lugs being laterally aligned with the first portion of the passage being free of studs such that in response to the rear suspension assembly being compressed to at least one position:

the portions of the plurality of lugs being laterally aligned with the first portion of the passage come into contact with the first portion of the passage; and

the plurality of studs are prevented from coming into contact with the first portion of the passage.

2. The snowmobile of claim 1 , wherein:

some of the plurality of studs are disposed to a right of the first portion of the passage; and

some of the plurality of studs are disposed to a left of the first portion of the passage.

3. The snowmobile of claim 1 , wherein:

the first portion of the passage extends longitudinally along a first lateral side of the heat exchanger;

a second portion of the passage defined by the at least one recess extends longitudinally along a second lateral side of the heat exchanger;

portions of the plurality of lugs being laterally aligned with the second portion of the passage being free of studs such that in response to the rear suspension assembly being compressed to the at least one position:

the portions of the plurality of lugs being laterally aligned with the second portion of the passage come into contact with the second portion of the passage; and

the plurality of studs are prevented from coming into contact with the second portion of the passage.

4. The snowmobile of claim 3 , wherein some of the plurality of studs are disposed laterally between the first and second portions of the passage.

5. The snowmobile of claim 4 , wherein:

some of the plurality of studs are disposed laterally outward of the first portion of the passage; and

some of the plurality of studs are disposed laterally outward of the second portion of the passage.

6. The snowmobile of claim 3 , wherein:

some of the plurality of studs are disposed laterally outward of the first portion of the passage; and

some of the plurality of studs are disposed laterally outward of the second portion of the passage.

7. The snowmobile of claim 1 , wherein:

the inlet and the outlet of the passage fluidly communicate with the motor; and

the heat exchanger assembly is adapted to have at least one motor fluid flowing therethrough for cooling the at least one motor fluid.

8. The snowmobile of claim 1 , wherein at least a portion of the passage is wider than at least another portion of the passage.

9. The snowmobile of claim 1 , wherein at least one of the inlet and the outlet is defined in the at least one of the front and rear portions extending below the middle portion.

10. The snowmobile of claim 9 , wherein:

the at least one of the front and rear portions extending below the middle portion is the front portion; and

the outlet is defined in the front portion.

11. The snowmobile of claim 1 , wherein:

the inlet is disposed near a first end of the passage; and

the outlet is disposed near a second end of the passage.

12. The snowmobile of claim 1 , wherein the passage extends longitudinally along a first lateral side of the heat exchanger, then laterally along the rear portion, then longitudinally along a second lateral side of the heat exchanger and then laterally along the front portion.

13. The snowmobile of claim 1 , wherein the passage extends at least in part along the middle portion and the at least one of the front and rear portions.

14. The snowmobile of claim 1 , wherein at least a portion of the passage is thicker than at least another portion of the passage.

15. The snowmobile of claim 1 , wherein the passage extends at least in part along the front portion; and

wherein a width of a portion of the passage extending along the front portion is at least three quarters of a width of the front portion.

16. The snowmobile of claim 1 , wherein:

the at least one of the front and rear portions extending below the middle portion is the front portion; and

the recess extends at least in part along the middle portion and the front portion and is curved to follow a curvature defined by the front portion and the middle portion.