Stefano, It might be coming from the check valve that feeds the brake booster. It's mounted on the intake manifold near #4 intake. Take it out and clean it with carb cleaner. My 71 GTV used to do that on the first start in the morning especially when the outside temps were low. It could also be in your booster, you could temporarily plug the vacuum line if cleaning the check valve doesn't help.
Dick Stachowiak East Syracuse, NY 71 GTV 71 Spider On Mar 25, 2015, at Wednesday March 25 8:07:20 PM, alfa-digest wrote: > Date: Wed, 25 Mar 2015 17:06:10 -0700 > From: Stefano Iachella <[email protected]> > Subject: [alfa] Whistle at startup > > Cats: > > I'm trying to figure out what is going on with my > 74 GTV: US Spica version. > > About every other time I start it up in the morning > a short whistle appears to come from the front, > possibly engine compartment. It lasts for about 1 > second, so I have not been able to diagnose it. > > Some things I've changed recently is the fan belt. > The brake booster hose, idle hose, and oil vapor > separator hose to cam cover have been changed > to silicone. These hose changes were over 6 mo > ago though. Fan belt is a few weeks. It is plenty > tight with 1/4" deflection at rest. > > Water Pump?? In preparation for that, I've called > around and these are on back order everywhere, > except Jon Norman who has doubled the price > since his supply is down and he doesn't know > when they will start making them again. > > Any other ideas? > > Thanks, > Stefano > Concord, CA -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
