this is how a clean engine looks like

4:48

8:42

6:18

21:58

10:11

6:39

4:38

13:00

10:30

6:01

14:41

20:54

14:08

12:05

4:22

32:50

12:16

19:41

7:40

20:01

3:25

23:53

14:21

16:33

3:58

10:04

13:23

11:37

16:57

12:19

11:25

1:14

2:25

24:08

9:36

9:51

12:22

2:12

5:22

4:30

5:55

5:52

15:00

10:03

3:16

7:14

13:08

2:08

12:03

15:01

11:24

15:34

9:52

2:47

12:52

00:35

1:57

9:04

8:27

7:24