Author Topic: fuel tank venting  (Read 3938 times)

sailprincess

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fuel tank venting
« on: March 27 2018, 03:44 »
We're on a 2002 Bav 40.Troubleshooting an engine issue and wondering about how the diesel tank vents. Anyone else out there with the same system? It seems to have two hoses that go to the same hole. One is the diesel fill hose and the other is a thinner vent hose. Both go to the diesel fill opening on the transom that have a metal, screw-on cap with a little chain holding it on. It seems that the diesel tank can only vent then when the cap is off and you are filling the tank? It is a very strange set up compared to most boats, and even other Bavarias we have seen have a separate hole outside for the diesel tank vent.

Salty

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Re: fuel tank venting
« Reply #1 on: March 27 2018, 06:09 »
We're on a 2002 Bav 40.Troubleshooting an engine issue and wondering about how the diesel tank vents. Anyone else out there with the same system? It seems to have two hoses that go to the same hole. One is the diesel fill hose and the other is a thinner vent hose. Both go to the diesel fill opening on the transom that have a metal, screw-on cap with a little chain holding it on. It seems that the diesel tank can only vent then when the cap is off and you are filling the tank? It is a very strange set up compared to most boats, and even other Bavarias we have seen have a separate hole outside for the diesel tank vent.

Exact same system on my B36(2002), but I’ve not yet had the problems you are experiencing despite on occasions running the engine for several hours, and including once or twice with the fuel supply valve shut :-\

tckearney

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Re: fuel tank venting
« Reply #2 on: March 27 2018, 09:24 »
on my B42 there is a vent near to the fuel filling point.  It does foam up and overflow if filled to fast,  I assume this is also an air  vent

Spirit of Mary

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Re: fuel tank venting
« Reply #3 on: March 28 2018, 12:22 »
We're on a 2002 Bav 40.Troubleshooting an engine issue and wondering about how the diesel tank vents. Anyone else out there with the same system? It seems to have two hoses that go to the same hole. One is the diesel fill hose and the other is a thinner vent hose. Both go to the diesel fill opening on the transom that have a metal, screw-on cap with a little chain holding it on. It seems that the diesel tank can only vent then when the cap is off and you are filling the tank? It is a very strange set up compared to most boats, and even other Bavarias we have seen have a separate hole outside for the diesel tank vent.

Exact same system on my B36(2002), but I’ve not yet had the problems you are experiencing despite on occasions running the engine for several hours, and including once or twice with the fuel supply valve shut :-\

Same on my BAV 38 2003. No problem running the engine for 10 or more hours.

tiger79

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Re: fuel tank venting
« Reply #4 on: March 28 2018, 18:47 »
We're on a 2002 Bav 40.Troubleshooting an engine issue and wondering about how the diesel tank vents. Anyone else out there with the same system? It seems to have two hoses that go to the same hole. One is the diesel fill hose and the other is a thinner vent hose. Both go to the diesel fill opening on the transom that have a metal, screw-on cap with a little chain holding it on. It seems that the diesel tank can only vent then when the cap is off and you are filling the tank? It is a very strange set up compared to most boats, and even other Bavarias we have seen have a separate hole outside for the diesel tank vent.

Exact same system on my B36(2002), but I’ve not yet had the problems you are experiencing despite on occasions running the engine for several hours, and including once or twice with the fuel supply valve shut :-\

So how does the tank vent?

sailprincess

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Re: fuel tank venting
« Reply #5 on: March 28 2018, 18:53 »
Exactly. That is what I am trying to understand. How can it run if it only vents when the fuel fill cap is off?

Spirit of Mary

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Re: fuel tank venting
« Reply #6 on: March 29 2018, 11:34 »
Exactly. That is what I am trying to understand. How can it run if it only vents when the fuel fill cap is off?

In 3 weeks I will be on the boat and try to find out how the vent works and if the filler cab needs to be off. Same system with the watertank(s)????

sailprincess

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Re: fuel tank venting
« Reply #7 on: March 29 2018, 14:50 »
Yes, same setup for the water tanks