Holley query

[Mad4slalom]

Hi all , seen this pipe mentioned a couple of times, read it can help with fuel evap from bowls when hot. Any thoughts ?TiA

 

[Roscobbc]

The septics will assure us that is a 'Bubba' device. If the carb is in good order, set-up correctly and float levels are correct........the only thing you'll get coming out of those 'vents' is possibly raw fuel in the event of a primary or secondary float needle failure where perhaps a piece of crap get wedged under the needle and allowing the float bowl to overflow and possibly pour out of the vent. Honestly......if the fuel overflow is that bad and you haven't noticed it all the rubber tube will do is make matters far worse and perhaps fill the inside of the air filter, and indeed the inlet manifold with raw fuel...........get a backfire and you are seriously toast.......literally!

 

[Mad4slalom]

The septics will assure us that is a 'Bubba' device. If the carb is in good order, set-up correctly and float levels are correct........the only thing you'll get comung out of those 'vents' is possibly raw fuel in the event of a primary or secondary float needle failure where perhaps a piece of crap get wedged under the needle and allowing the float bowl to overflow and possibly pot out of the vent. Honestly......if the overflow is that bad and you haven't noticed it all the rubber tube will do is make matter worse, perhaps fill the inside of the air filter with raw fuel...........get a backside and you are seriously copulated!

Thanks ross

 

[CaptainK]

I put one of those thermal gaskets under my carb to help with fuel evap. Previously after driving the car, and engine was hot, if I had to restart the engine it was hard to do. Now much easier.

 

[Mad4slalom]

I put one of those thermal gaskets under my carb to help with fuel evap. Previously after driving the car, and engine was hot, if I had to restart the engine it was hard to do. Now much easier.

Thanks captain, mine is fine for15 mins restarting from hot , 20mins or more and I have to pump gas pedal as fuel has disappeared , motor runs really cool so pretty sure it is not boiling away , presume just evaporating. Carb not hot to touch. Just how it is I guess.

 

[Roscobbc]

It's worthwhile 'tracing' fuel line to fuel pump/then to carb and see how close to a heat source (exhaust manifold/header tube) it gets. Options (if too close) are to re-route the fuel line - or wrap it with insulation. On mine fuel lines (and break lines) in the engine compartment run sling the top of the chassis........not particularly close to a header tub.......I simply sourced some of that self adhesive aluminium cellular insulation/heat shield materia, cut to length required, then cut that about an inch or so wide, peel-off the backing, slide it under the fuel/or brake pipe and effectively wrap the pipe. Seemed to help mine.

 

[Mad4slalom]

It's worthwhile 'tracing' fuel line to fuel pump/then to carb and see how close to a heat source (exhaust manifold/header tube) it gets. Options (if too close) are to re-route the fuel line - or wrap it with insulation. On mine fuel lines (and break lines) in the engine compartment run sling the top of the chassis........not particularly close to a header tub.......I simply sourced some of that self adhesive aluminium cellular insulation/heat shield materia, cut to length required, then cut that about an inch or so wide, peel-off the backing, slide it under the fuel/or brake pipe and effectively wrap the pipe. Seemed to help mine.

Thanks I will look at their route

 

[Oneball]

That’s the bubba version of the Holley Off Road Vent Tube. Its purpose is to stop raw fuel splashing out of the float chambers and into the inlet at severe angles of attack and heavy braking. It can help if the fuel is boiling in the float chambers and fuel lines and this expansion is putting raw fuel out of the vents into the intake. If your car won’t start because it’s flooded after sitting it might help but if it won’t start because the fuel has evaporated it won’t.

 

[Oneball]

PS I have an insulated spacer in both my cars and in both cases it cured hot start issues.

 

[Roscobbc]

Problem using spacer is that on some engine/inlet manifold combinations there is limited height available