V6 135HP.Leaking Fuel at Silencer Box??? What Next.

[aussieflash]

G'day all,Completed carb rebuild and link n sync,timing etc.Started motor today and set idle.Sounds good at idle and very responsive with a few short revs(on hose).
Problem is it's leaking fuel at silence box via small hose fitted at box.It used to do it before as well but
not all the time.Can anyone explain why this is leaking and what does the hose do.Comes from the reed block.Thanks for any help.

 

[j_martin]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

Check your hose routing. There's hoses from check valves that drain fuel from the reed blocks to the opposite cylinder, (bleeed lines) and there's one hose that goes to a distributed vacuum channel in the reed block that is supposed to evacuate any fuel leakage from the air box. You must have hoses routed wrong.

 

[aussieflash]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

Only one hose to air box which is on a thread fitting.Had to remove when took carbs off,then put back on when job finished.fuel from this line is spitting into air box.Should this line be
sucking from air box or should there be a second line connected?........why me.

 

[j_martin]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

I guess it's going to take detailed pictures to see what you have.

There should be 5 or 6 bleed lines on the engine, and the fittings for them, which are check valves, are placed in similar locations to their related reed blocks. One similar fitting is out of position, I believe just starboard of #4 bleed valve. (on a vertical reed engine) That's the one that goes to the air box. I think you mixed that one up with a bleed line, which will be putting out fuel.

Aussie, you've been around long enough to know what's coming next.




It's in the book.

 

[Coloradolakeboy]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

Problem is it's leaking fuel at silence box via small hose fitted at box.It used to do it before as well but
not all the time.

When I got my '80 175, that bleeder line was not connected to the silencer box and was hanging loose. The motor was running very rich here at 5000 ft. That hose was dripping quite a bit of fuel at idle. I reattached it and after carbs were rebuilt and high altitude jets installed, I have never seen it drip into the transom well. So is it a "drain" into the transom well for excess fuel?
I looked in my Merc Sevice manual and there is no mention of it that I could find.

 

[aussieflash]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

Thanks John,yes my manual has page on bleed lines for 5 or 6 lines.Manual said for v150,175,200 model.Im presuming that covers my V135 as its not mentioned.Though it doesn't explain what they do.Thanks
for explaining.I'll check the lines today.

 

[aussieflash]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

Thanks John,I've never touched bleed lines at engine,only at air box.I went and checked
routing anyway and.......BINGO...some goose has put vac line to #1cyl and bleed valve at #4 to Air Box.Swapped them over after taking #2 carb off.I'm guessing it's been that way for
years.Probably need to link n sync again.

 

[j_martin]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

Thanks John,I've never touched bleed lines at engine,only at air box.I went and checked
routing anyway and.......BINGO...some goose has put vac line to #1cyl and bleed valve at #4 to Air Box.Swapped them over after taking #2 carb off.I'm guessing it's been that way for
years.Probably need to link n sync again.

Just carb butterfly synchronization and throttle pickup. Maybe idle speed if it was dropping #4.

 

[aussieflash]

Re: V6 135HP.Leaking Fuel at Silencer Box??? What Next.

All done,timing,sync etc,and not a drop of fuel from air box.Thanks again for your help J.M.