isda

Can someone pls. tell me what this is?

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Could someone please tell me what the item in the bottom right of the image is?  One line attaches to the fuel pump, one line to the carb, one to vacuum, another line runs underneath the car and attaches to a metal line.  Thanks 

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Thats the fuel by pass valve it returns excess fuel to the tank on smoged cars via the metal pipe that runs under the car. Not strictly necessary but if you do remove it you'll need to block the return line off at the tank to prevent fuel leaks. 

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Not a bypass valve.  It relieves (bleeds off) the fuel line pressure when the vacuum is lost on shutdown.  Fuel under pressure in the line after shutdown will continue to fill the carb bowl if there is some boil off, exasperating a restart with a partial flooded condition.  It could be called a part of the smog equipment and came along at the same time.

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Yup - just run fuel hose from the fuel pump output side to the carb directly.

 

And Son of Marty's comment is soooo true... when I first got my '75 it had been stripped of all smog equipment, but the return pipe still ran under the car to the tank. The first time I filled the tank to the top and took a short drive it reeked of fuel. Got home and parked and gas was dripping (gushing) out of the fuel pipe down by the frame rail where the PO never plugged it.

 

I am assuming his solution was to never fill the tank full !! 

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By the way, you have some nice autos in your "stable".. but you have 12 posts so I am guessing your '02 is the new horse in town?

 

Post a few pix of your '73... 

 

 

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Another comment - I can't find my image, but if you Google 'BMW 2002 smog equipment diagram' or search this site, there is a nice graphic of all the crap they added by 76... that you probably will want to yank off :)

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Excellent!  Thanks so much for the replies, very helpful as usual.  Will be rerouting the fuel line tonight before the rain hits tomorrow. 

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1 hour ago, worzella said:

Another comment - I can't find my image, but if you Google 'BMW 2002 smog equipment diagram' or search this site, there is a nice graphic of all the crap they added by 76... that you probably will want to yank off :)

 

Here's the sticker from my '76:

'76 Emmisions Sticker.jpg

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Just removed and rerouted the fuel line directly to the carb and capped the vacuum line at the source.  Runs smoother than before, no more fluctuating idle.  Next project, electric fuel pump.

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Ha ha - not the seats you usually expect to see in a 40+ yr old car. Nice ! 

 

Nice color.. is it Fjord like mine :)

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The seats that were in the car when I purchased it were pretty beaten up.  Went to the BMW dismantler and picked up a pair of seats for $200.  A friend of mine welded the support brackets.  Color is similar to Fjord blue, Sherwin Williams special ;)

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