Sounds like you have accurately diagnosed the problem. I had a 413 that did
the same thing. I replaced the manifold seals, and it was fixed.
>From: KerryPinkerton <pinkertonk@xxxxxxxxx>
>Reply-To: mailing-list@xxxxxxxxxxxxxxxx
>To: IML <mailing-list@xxxxxxxxxxxxxxxx>
>Subject: IML: 440 vac leak??
>Date: Fri, 15 Mar 2002 15:16:59 -0800 (PST)
>
>Well, I'm approaching stumped. My 73 runs like crap
>and I've messed with it til I'm about out of ideas.
>
>Here are the symptoms:
>
>Timing set at 10 degrees BTDC with the Vac adv
>disconnected and plugged.
>
>Vac gauge shows about 17, it used to be about 20.
>
>I have adjusted on the carb and timing and made little
>change in the vac.
>
>i have disconnected and plugged ALL vac lines with NO
>change on the vac guage.
>
>The car runs right now as well as it's run recently
>WITH THE BREATHER OFF. With the breather on it is
>very FLAT at high RPM and has a slight bog if you
>punch it at idle. Turning the breather lid upside
>down and letting more air in helps but not as much as
>removing the breather completely.
>
>Vacumm leak you say. I've tried the starter spray,
>propane trick and get no RPM or engine noise change.
>
>Compression is 130 per cyl.
>
>Now for the interesting stuff, under some conditions
>of timing, I can screw the idle jets all the way in
>and the car still runs which makes me think vacuum
>leak. Also the car will not idle down below about 600
>RPM even with the screw completly backed out.
>
>Plugs are about a year old but probably don't have a
>1000 miles on the, same with wires, rotor button, and
>cap. Cap does not show signs of damage or wear.
>
>At this point, the only think I can think of is that
>there is a vacuum leak around the intake manifold,
>probably on the bottom where I can't get to it.
>
>Before I pull it off, I'd like to hear from the wisdom
>of the group.
>
>Oh, one piece of good news is that my 'ticking' sound
>was a bad exhaust manifold which has now been
>replaced.
>
>Kerryp
>
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