Out Banjo persistant leak

[libbydiesel]

The pedestal is on less than 1% of the pumps and the copper washer under it has nothing at all to do with the banjo fitting except that it is in the vicinity...  Obviously I wasn't talking about the copper washer under the pedestal, if you happen to be one of the very few who even has one.  I was talking about the two around the OUT banjo (note thread title...).  Further, you even state that 'the threads of the OUT bolt lead directly into the case' and so in that instance you couldn't have been talking about a pump equipped with a pedestal/standoff.

[92EcoDiesel Jetta]

The pedestal is on less than 1% of the pumps and the copper washer under it has nothing at all to do with the banjo fitting except that it is in the vicinity...  Obviously I wasn't talking about the copper washer under the pedestal, if you happen to be one of the very few who even has one.  I was talking about the two around the OUT banjo (note thread title...).  Further, you even state that 'the threads of the OUT bolt lead directly into the case' and so in that instance you couldn't have been talking about a pump equipped with a pedestal/standoff.

My car as well as my spare engine has the pedestal. I may have used  out bolt and pedestal interchangeably but I meant pedestal (I was half asleep so please excuse me). My previous post was in response to a post from you which was deleted before I was able to quote it where you stated the the copper washer under the pedestal is not under pressure. Maybe you did not say that, hey I was half asleep. 

[R.O.R-2.0]

Off topic somewhat, but where does one find replacement copper washers, my import supplier could not find the ones I need for my oil return thanks.

any industrial supply or hydraulic shop should have what you seek..

[92EcoDiesel Jetta]

Furthermore, for the same reasoning I gave for the pedestal washer, it would also apply to the banjo/ out bolt washers. i.e. if you remove the out bolt, you see internal case pressure at the pump opening. Put it back and the copper washers see case pressure, unless the out bolt threads form a perfect seal. Help me out but I can't see it any other way.

[92EcoDiesel Jetta]

To the OP, a good way to find the source of your leak is pressurize your pump and squirt soapy water in suspect areas and look for bubbles.

[R.O.R-2.0]

To the OP, a good way to find the source of your leak is pressurize your pump and squirt soapy water in suspect areas and look for bubbles.

pressurize it with AIR, not fuel, just to clarify..

[92EcoDiesel Jetta]

A sure way to test if there is pressure behind the out bolt copper washers is to loosen the out bolt a little while the engine is running. If there is no pressure, fuel should not squirt out. If there is (around 60 psi at idle), you should get a pretty good squirt so wear goggles and take precautions.

[libbydiesel]

I did not delete any posts that you replied to.  I did delete one post where I reiterated what I had said previously, but in the interest of reducing redundancy I deleted it to reduce redundancy.  

I guess you are asking for more redundancy and so I will accommodate you because you are asking for more redundancy.  The copper washers of the banjo are outside the threads of the out bolt.  I haven't even made any attempt to do the calcs on how much fuel flows up the gap of the threads of the OUT bolt but I certainly believe it to be significantly less than what flows out of the orifice of the OUT bolt.  The area of the return line is many times larger than the combined area of the orifice and whatever minuscule gap there is in the threads of the out bolt/case and so there is not internal pressure outside the case threads or orifice of the out bolt.  The boundary of the internal pressure is the vane pump and pressure regulator on the inlet side (no pressure on that banjo either) and the OUT bolt itself on the outlet side.  The banjo and copper washers are BEYOND the OUT bolt and so are not under any pressure.  The copper washers do not seal the threads of the OUT bolt.  They seal the top of the banjo to the bottom of the head of the OUT bolt and the bottom of the banjo to the case.  If you believe that the copper washers are under internal pump pressure then you must also believe that internal pump pressure extends down the return line to the fuel tank and through the tank vent to atmosphere...

[libbydiesel]

A sure way to test if there is pressure behind the out bolt copper washers is to loosen the out bolt a little while the engine is running. If there is no pressure, fuel should not squirt out. If there is (around 60 psi at idle), you should get a pretty good squirt so wear goggles and take precautions.

That's a terrible test.  Gravity coupled with the fact the fuel weighs more than the air that displaces it will cause fuel to flow out if there is a gap.

[R.O.R-2.0]

A sure way to test if there is pressure behind the out bolt copper washers is to loosen the out bolt a little while the engine is running. If there is no pressure, fuel should not squirt out. If there is (around 60 psi at idle), you should get a pretty good squirt so wear goggles and take precautions.

That's a terrible test.  Gravity coupled with the fact the fuel weighs more than the air that displaces it will cause fuel to flow out if there is a gap.

x2

fuel is going to leak out when you loosen the out bolt, no matter if the return line is clogged or not...

[92EcoDiesel Jetta]

I did not delete any posts that you replied to.  I did delete one post where I reiterated what I had said previously, but in the interest of reducing redundancy I deleted it to reduce redundancy.  

I guess you are asking for more redundancy and so I will accommodate you because you are asking for more redundancy.  The copper washers of the banjo are outside the threads of the out bolt.  I haven't even made any attempt to do the calcs on how much fuel flows up the gap of the threads of the OUT bolt but I certainly believe it to be significantly less than what flows out of the orifice of the OUT bolt.  The area of the return line is many times larger than the combined area of the orifice and whatever minuscule gap there is in the threads of the out bolt/case and so there is not internal pressure outside the case threads or orifice of the out bolt.  The boundary of the internal pressure is the vane pump and pressure regulator on the inlet side (no pressure on that banjo either) and the OUT bolt itself on the outlet side.  The banjo and copper washers are BEYOND the OUT bolt and so are not under any pressure.  The copper washers do not seal the threads of the OUT bolt.  They seal the top of the banjo to the bottom of the head of the OUT bolt and the bottom of the banjo to the case.  If you believe that the copper washers are under internal pump pressure then you must also believe that internal pump pressure extends down the return line to the fuel tank and through the tank vent to atmosphere...

I will have to dig out my spare pedestal/out bolt and have a look. I just can't see there is zero pressure behind the copper washers.

[libbydiesel]

What do you find confusing in my explanation?

Imagine just an out bolt bolted all the way into a pump, no banjo or washers.  If it is run that way, internal pressure will still be maintained by the bolt/orifice.  Outside that boundary there is no internal pressure regardless of whether the washers or banjo are present.  Granted fuel will squirt out of the orifice a weep a little around the threads, but that leakage is metered and accounted for by Bosch in the design of the pump.  Beyond that point, when banjo, washers and hose are present, gravity pulls the fuel back to the tank.   

[sgnimj96]

Wow.     I just got back.     I tightened the banjo one more time and then had to drive it on the interstate to get back home with the car - a long drive.      As it turns out,  I had a restriction in the line coming from the tank.     It was quite a drama:   first I thought it was just an air leak in the clear line coming from the fuel filter to the IP,  so I refit and tightened that and off I went down the highway (with the out banjo leaking).      Funny how real fuel flow problems happen after time at highway speeds, just when you don't want them to happen.    KInda scary and dangerous things like that can be.   I thought I just had a leak.     
          So I lost power on the interstate;  made it to an exit (luckily),  popped the hood and found the clear line full of air.  All hoses are tight.   This car has an electric fuel pump, which IS cool,   so I turned it on and left it on (didn't think I needed it while driving but it helped so I continued on).       30 minutes later I lost power again,  barely made to an exit and coasted into a truck stop sputtering-   in the middle of nowhere.    Disconnected the electric pump out hose, checked it,  still pumped fuel (but seemed kind of weak).   Then disconnected the other end of that fuel hose (at the filter) did a blow test.   I should have done this in the garage-    main line from the filter to the tank (disconnected at both ends) is clogged.       LUCKILY I had some 1/4" clear fuel line,  had to heat it with a lighter a little but managed to push it onto fuel filter inlet and ran it to the electric fuel pump (in the back of the car).      Used the electric fuel pump to push the air out of new fuel line (out the bleeder on the filter)-  although it took it a while, which seemed odd.      So with a new fuel line off I went down the interstate on my long journey.  Like an hour or two later,    middle of the night,  loses power! Hit the fuel pump switch and it helped but not for long.   Sputtering and feathering the pedal (it actually died a couple times) but I managed to restart with clutch with my leftover speed and  finally coast into convenience store off the highway somewhere in Louisiana.     Feeling lucky, but stupid.     Last ditch effort- bypass the electric fuel pump.   A police SUV is casually hanging out watching me.    I ran the fuel pump a little more to see if it would get some of the air out of the clear line to the IP and it did a little but was now basically worthless.    I had nothing to connect the hoses together to bypass the electric pump but...   Luckily!  in my toolbox I had a 1/4" deep-well socket (1/4" drive) that would fit with a little forcing (actually worked pretty good because they were two different sized hoses)     Managed to start her back up.     After a bit all the air was purged and I was out of there.

    I drove from Texas to Florida, and For some reason,  the out banjo on the IP doesn't seem to be leaking anymore after that or is just hard to notice (I made a lot of stops checking things)   KInda neat having a clear fuel hose running across the passenger seat where you can keep an eye on it.  NOT!       
   Is that missing leak just a coincidence?

[TylerDurden]

Since the car is relatively new to you, it is hard to know what went into the tank. I would give it a healthy dose of Power Service 911 to help dissolve any wax or foreign oil that the PO might used that could be blocking the tank screen or pump. Bypass/remove the water separator, if it is still in line.

I'd ensure the return line is flowing freely with light application of compressed air and listen for bubbles in the tank.

As for the leaking banjo, a fine scratch on the IP case or bolt can create a dribble. It may self-seal for awhile, but come back later. Close inspection with a magnifier might reveal potential leaks. A very very light smear of sealant on the washers might resolve a lingering drip.

[JerryGTD]

When I had something similar happen to me, I just ran a clear fuel line from the fuel filter through the top rear of the hood, back into the passenger front window, out the rear passenger window, then into the gas tank through the filler neck, thus bypassing the fuel pickup in the tank.