Thanks to everyone for all the replies.

Not really -- venting a little liquid won't change the tank pressure.  You
> very likely have an air leak somewhere at the upper end of the flue/intake
> system, either bad O-rings at the tube-to-inner-fitting joint or leakage
> between inner and outer fitting.  The angle of the inner fitting to the body
> has to be very close all by itself; you can't just hog it into place with
> the fitting screws.  A broomstick fits nicely into the fitting to adjust it.
>  I also routinely use RTV between inner fitting and body and outer fitting.
>  Bad O-rings can also be helped out with RTV.
>
When you say the upper end of the flue/intake system, do you mean the part
that is up at the whole the the body of the van?  I don't believe I have any
o-rings there at all.  I don't remember any from when I took it apart and
put it back together.  Where are these o-rings?  And can you clarify for me
what you mean by the inner and outer fittings?  I'm having trouble picturing
it right now (and, unfortunately, it seems that the bentley has no pictures
of this part of the setup).  The only rubber seal I remember from this part
at all is the big rubber backing to the whole vent assembly, which is
clearly visible from outside the van.  I used sealant between this and the
chassis of the van, mostly because I was worried about moisture leaking in
here.

Thanks very much for any help.   I would love to get the fridge back to
where it works off propane while driving.

-Wes