Logo
FULL SITE MENU

1977 Mercury 850 internal fuel hose?

O

oldisgood

Member
What is the rubber hose (factory painted black) that runs vertically at the front of the motor (behind the starter motor flange in the photo)? At the bottom fitting, there's a small tube that runs to the front of the lower cowl.
At the rear of the motor, there's a small tube (also factory painted black) on the right side of the motor running from the top to bottom, which I think I understand is the cylinder bleed hose which can be updated with a vacuum line from an autoparts store (?).
IMG_9599.JPGIMG_9602.JPG
 
I think the small tube in image 1 is supposed to be connected to the top fitting in image 2. Yes they're oil transfer lines.
 
Sorry; the images aren't very clear...but in image 2, the tube is already connected to fittings at the top and bottom. The image 2 tube is relatively small diameter (roughly vacuum line sized; I believe it's the cylinder bleed hose @ 0.077 I.D.) The image 1 hose is the diameter of the fuel lines, and is connected to fittings at top and bottom; bottom small tube connects to bottom of front cowl... venting to outside (?). Here's a photo of the small tube connected at the bottom fitting from image 1. IMG_9609.JPG
 
I (may have) figured out part of the puzzle. From the marineengine.com parts info, an illustration shows what I think is the cylinder bleed hose (0.077 I.D.) #17- #20 on the left (which is mounted towards the rear of the engine), and on the right side of the illustration is shown the larger-diameter "balance hose" #21-#25, with reference to connection to an air inlet. But what does this "balance hose" system do?
balance hose.JPG
 
HI, I see the small hose disconnected, I had a broken brass spigot, I found out that it goes to the air plenum, But it has a free hole on the outside, that should remain that way? It would take in air from outside the carburetors
 
Back
Top