Forget that. The Valoy is a cheaper Focomat I and has absolutely nothing
to do with the modern V35.

I had the same problem, long exposure times with my newly aquired V35.
After checking the bulb (it _must_ be a Philips 13139 for all but the oldest
V35) and replacing the installed Osram bulb with the correct Philips
bulb, the exposure time dropped to 1/10! Now it is almost to bright
for small formats (10x15cm takes 2-3s @ f5.6)

The V35 has a sophisticated mixing box system and absolutely needs
the correct bulb. There is no replacement type for the Philips
bulb, the sometimes named Osram 64615 doesn't work!

Martin

Thanks for all the answers so far.
Some technical details
film is Ilford FP4 processed to standard specs, paper is Ilford MG IV
also processed in standard 1+9 MG developer at 20C.
As the prints were quite important, we took the negs to my lab and
printed on a Durst 605 with colorhead. Where we had to expose 60 to 90
seconds on the Leitz at F 5.6 (Focotar 2,8/40), we could print the
same negs to 30x40 cm on the Durst at 20 - 25 seconds at F8 (Componon
S 2,8/50).
The mixbox on my Durst is always set to 66, even for 35 work. I guess
switching it to 35 would make the exposures even shorter, didn't try
that though as the result was already obvious.

The Leitz was a recent Ebay purchase and we had no experience with it
but the difference seems too big, that's why I wanted to find out if
this is normal or mayhbe there might be something wrong with it.
As leitz has quite a reasonable reputation, I ruled out a construction
flaw.

Unfortunately (well....) there is some holiday and abroad fotowork
first. After that We will try to check if the alternative bulb makes a
difference as explained on one of the links I received
(http://www.bonavolta.ch/hobby/en/photo/v35.htm#Bulb%20Specifications)

thanks
Jacky D.