Hi, I just replaced all the under the hood fuel lines and am about to do the newer Bosch primer change over. I replaced the injector fuel return lines a couple of nights ago and have driven it a few times since. The mileage appears down somewhat but I was not concerned since my next job is to replace the glow plugs and later in the winter new injector nozzles ( if a Diesel Purge does not do the trick). After I popped the hood this a.m. I smelled fuel stronger than usual and looked under the car to see a nice puddle at a fairly strong rate.
Backtracking I looked at the return lines and saw the last 2 were leaking at a visible rate. I was fortunate enough and lazy enough that I left my 2x3 steel drainge sheet pan beneath the car over the last few nights or I would have a gapping hole in my asphalt driveway.
I ran the engine around town and on the highway after I replaced the return lines and happily found no drips no runs no errors. As a side note I changed the lines to VITON.
Now the last few evenings the temp here has dropped into the 55-65 degree range so my first thought was how that would effect the fuel system.
I cleaned up around the still connected fuel lines with electromotive cleaner and used compressor air to dry. The fuel was still weeping at a good rate even though I had tried to reseat the hose ends.
The car is sitting in full sun and it is now almost 80 degrees out. I popped open the fuel tank cap and WHOOOOOOSH!!!
Now the fuel has stopped. I recut new Viton hoses and made them a little longer in case being to short it had pulled the contact between the steel injector nipple and the hose. I have not gotten under the car yet to do the tank lines as well as the strainer etc but does it seem possible that the tank vent is clogged and that the temp change was preventing the fuel from returning and in fact the temp increase raised the return line pressure just enough to make the 2 most poorly seated leak ???
Where exactly is the tank vent and thoughts on clearing out debris that may be blocking it ????? I am going back out to do the primer pump and clean/service the Alda system so I will check this thread again in about an hour.
Thanks
Alan

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