I have this green thing in the air filter housing. According to BMW ETK they call it 'voltage regulator' which is mind boggling since there are no wires connected to it. It just has 2 vacuum hoses.
It's item number 6 here:
https://www.realoem.com/bmw/enUS/showpa ... Id=13_0601
Anybody know the function of this thing? How to check if it's working?
Function of BMW p/n: 13711274704
- Jeroen
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Re: Function of BMW p/n: 13711274704
Clearly not a voltage regulator, but a vacuum valve instead. I believe it's supposed to limit the air flow. Never ever bothered to investigate its purpose or functionality, but I never ran into any issues with carburettors that made me dig that deep haha
Regards/groeten, Jeroen
- Peter V.
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Re: Function of BMW p/n: 13711274704
This is a wax operated vacuumvalve. This opens and closes the valve in the airfilterunit to get fresh air during warm temperature and preheated air (exhaustmanifold) during colder temperature.
Gr Peter V.
.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.
BMW E21, 1981 320/6 Ascot Grau.
BMW E85, 2004 Z4 2.5i Sterling Grau.
BMW F31, 2017 320dA EDE Luxuryline Mineral Grau.
.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.
BMW E21, 1981 320/6 Ascot Grau.
BMW E85, 2004 Z4 2.5i Sterling Grau.
BMW F31, 2017 320dA EDE Luxuryline Mineral Grau.
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Re: Function of BMW p/n: 13711274704
Valuable info thanks Peter!
How can I test its functionality though? It seems blocked when I blow into it.
I doubt it's functional since 1981. Is it worth replacing?
How can I test its functionality though? It seems blocked when I blow into it.
I doubt it's functional since 1981. Is it worth replacing?
- Peter V.
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- Posts: 11992
- Joined: Sun Mar 30, 2008 12:42 pm
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Re: Function of BMW p/n: 13711274704
That depends on the position of the valve in the airfilterunit.
When it is open in the direction of the fresh air I would not make a big trouble out of it.
Maybe if you place the part in the refrigiator and test it it could be in open connection.
Gr Peter V.
.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.
BMW E21, 1981 320/6 Ascot Grau.
BMW E85, 2004 Z4 2.5i Sterling Grau.
BMW F31, 2017 320dA EDE Luxuryline Mineral Grau.
.Some say he eats nuts and bolts for breakfast, all we know is he is called the carburetorman.
BMW E21, 1981 320/6 Ascot Grau.
BMW E85, 2004 Z4 2.5i Sterling Grau.
BMW F31, 2017 320dA EDE Luxuryline Mineral Grau.