Date: Mon, 27 Aug 2012 20:08:13 -0700
Reply-To: neil n <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: neil n <musomuso@GMAIL.COM>
Subject: Re: Poor Hot Start Discovery - midway through solution
In-Reply-To: <503b2264.8877cd0a.70a9.ffffe620@mx.google.com>
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Right.
So, further to that, I now recall seeing what appeared to be a restrictor
in the "T" boot I showed in my image.
And obviously I wasn't 100% clearly understanding the charcoal canister
purge process. With a broken purge valve diaphragm in mind, I saw" fuel
vapours passing willy nilly through the hose that connects to the intake,
into the intake.
Sorry for taking up bandwidth with all that! ;)
Neil.
On Mon, Aug 27, 2012 at 12:26 AM, David Beierl <dbeierl@attglobal.net>wrote:
> I was even more mixed up than I thought. Referring to 20.33 - fuel vapors
> come from the tank and pass freely into the charcoal canister where they
> are in theory adsorbed onto the surface of the activated charcoal therein.
> Air, and any vapor that is not adsorbed, passes out of the bottom of the
> canister into the airbox, between filter and AFM.
>
> When the engine runs and the throttle is opened slightly, a vacuum port in
> the throttle body is uncovered and sucks (through a tiny orifice) on the
> activating line of the vacuum-operated purging valve. This opens the
> valve, allowing manifold pressure to act (through a somewhat larger
> orifice) on the canister, pulling filtered air slowly up through it from
> inside the airbox and carrying along such molecules of gasoline as detach
> themselves from the activated charcoal.
>
> Bentley is opaque on whether the 2.1l setup has a restricting orifice on
> the canister suction line or whether it's only the 1.9l, where it's built
> into an angled tee in the hose passing from the intake manifold to the
> auxiliary air regulator. I suspect it does, however, because since this
> isn't passing through the AFM it is in effect a vacuum leak, so they'd want
> to keep it small.
>
> Sorry for the mixup. I still don't think it's going to have any practical
> effect on starting.
>
> Yours,
> d
>
>
>
--
Neil n
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