Mercruise 120 enginefuel pump 3 ports

[kevinsrea]

"hi guys,
i have an old 4 cy

"hi guys,
i have an old 4 cylinder 120 mercruiser.
the fuel pump on the side has 3 hoses, the top two are input fuel and output to the carburetor, but there is one hose on the bottom ? any one know what this hose if for ?

thanks,
Kevin
[email protected]"

 

[Bt Doctur]

that is a safety device. It go

that is a safety device. It goes up to the carb. it allows you to see if the diaphram has ruptured in the fuel pump AND is also a vent line for the rubber diaphram. It must be kept open or the fuel pump will not work correctly

 

[kevinsrea]

"so, you say it goes up to the

"so, you say it goes up to the carb ?
where on the carb ?

kevin"

 

[Bt Doctur]

should be a small brass fittin

should be a small brass fitting either on the body above the throttle plate or the flame arrestor.
http://i57.photobucket.com/albums/g219/BtDoctur/IMG_1358.jpg"

 

[kevinsrea]

"so, it's just vented to t

"so, it's just vented to the air ?

kevin
ps.. thanks for your help on this.."

 

[guyjg]

"Look at #s 7 & 8

[url=

"Look at #s 7 & 8

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=%2068582&ivar=images/CRUI SER/68582/7.png&inbr=1587&bnbr=4&bdesc=FUEL+PUMP%2C+FUEL+FILTER+AND+CARBURETOR

Not vented into the air; the plastic tube is attached to the top of the carb rear to a nipple."

 

[guyjg]

"Look at the top front view of

"Look at the top front view of the carb. There is a square notched out area. The "L" nipple is just below it and pointing to the right.

http://www.marineengine.com/parts/additional-photos.php?item=MER3310-860070A+2&m ode=enlarge&p=0&g=/parts/images/hg/mer/1628.jpg"&title=+Mercury+Quicksilver+3310- 860070A+2+MERCARB+-+120/2.5L-+140/3.0L+"