Flame Arrestor w/Fuel Vent Connection

[itxone]

Working on a 1987 5.7 and I noticed the previous owner hadn't connected the fuel pump vent hose to the flame arrestor. The flame arrestor in the boat has a couple of ports for crankcase venting but no port for the fuel vent line. They sell a bolt on attachment but I have no idea how exactly it should bolt on and if I need to drill a hole through the arrestor.

I've looked online at possible replacement arrestors but haven't see any that have all three ports.

Any suggestions?

 

[Scott06]

Normally the fuel pump vent line goes on a barb on the carb around the airhorn Not on the flame arrestor If your carb doesnt have a barb it is possible that some one swapped in a non marine carb which is hazzardous. Do you have a pic the your carb without the flame arrestor on it

 

[dubs283]

the fuel pump does not have a vent, the yellow/clearish line you are referring to connects to the spill barb on the fuel pump. the reason for the clear fuel line to the carburetor is in case of a diaphragm rupture in the fuel pump resulting in raw fuel being dumped out the side, the barb and line prevent fuel from being dumped directly into the bilge resulting in a potential fire hazard.

rochester and weber carburetors have a barb fitting in the air horn for the clear line to be connected to, very few flame arrestors have the line connected to them

 

[Paintman1960]

I drilled and tapped a hole install the fitting into top of air horn, slotted the arrester to fit in a Holley carb

 

[itxone]

Normally the fuel pump vent line goes on a barb on the carb around the airhorn Not on the flame arrestor If your carb doesnt have a barb it is possible that some one swapped in a non marine carb which is hazzardous. Do you have a pic the your carb without the flame arrestor on it

Not handy, but the carb is a Holley 4160 (600 cfm). Just had it rebuilt over the winter.

 

[itxone]

I drilled and tapped a hole install the fitting into top of air horn, slotted the arrester to fit in a Holley carb

I've scoured the web and have seen people mention doing something similar. Have any pics to share?

 

[Bondo]

Not handy, but the carb is a Holley 4160 (600 cfm). Just had it rebuilt over the winter.

Ayuh,..... That's not a Merc carb,.....

Merc hasn't used a Holley carb since the ole Fords of the '70s,....

 

[Paintman1960]

I've scoured the web and have seen people mention doing something similar. Have any pics to share?

I will get ya a pic ..

 

[Bt Doctur]

All mechanical fuel pumps must have a vent hole/bard otherwise they would not work. The diaphram moves up and down and the air under the diaphram needs a place to go in and out. /in auto applications a leaker goes down under your car. In boats thats not a good idea. The vent hose goes to the carb to:
allow the diaphram to vent
allows you to see fuel in the hose it it has failed
alerts you to a leaking diaphram

 

[Scott06]

Bout halfway down this page shows the location of the overflow tube on a marine 4160 https://marinecarburetor.com/Y41-4160MercruiserOMCVolvoPenta.htm

 

[itxone]

Ayuh,..... That's not a Merc carb,.....

Merc hasn't used a Holley carb since the ole Fords of the '70s,....

There was a Holley 4011 in the Seloc but I didn't look to see how far back in the past it was used. This engine had been gone through at some point in the past 10 years or so and had the carb, intake and ignition updated..

Bout halfway down this page shows the location of the overflow tube on a marine 4160 https://marinecarburetor.com/Y41-4160MercruiserOMCVolvoPenta.htm

Thanks Scott! I noticed that port on the carb too and had been researching if it could be used.

Bout halfway down this page shows the location of the overflow tube on a marine 4160 https://marinecarburetor.com/Y41-4160MercruiserOMCVolvoPenta.htm

 

[Paintman1960]

 

[itxone]

View attachment 342390

Thanks Paintman! It sounds like I'll be able to connect directly to the carb but if not this might be option B.

 

[Paintman1960]

Yer welcome, I seen the carb in the link with the fitting.
This new Marine Holley i bought did'nt have that fitting, so I got creative