Date: Wed, 26 Sep 2007 16:32:16 -0700
Reply-To: Old Volks Home <oldvolkshome@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Old Volks Home <oldvolkshome@GMAIL.COM>
Subject: Re: An Auxiliary Air Regulator puzzle
In-Reply-To: <46FADEF9.8050502@gmail.com>
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I've often wondered about that diagnostic/troubleshoot that Bentley says
about the Aux Air Valve and have felt that it was bogus. The best way how
you did it - on the bench to see if it closes at all when 12 volts is
applied.
In fact the testing procedure outlined for the AAR is similar in the Type 2
68-79 Bentley and it is the same part as used on the Air Cooled Vanagons and
83.5-85 Wasserboxers (I've paraphrased and corrected some erroneous
sub-procedures that if done the Bentley way would have created a HUGE vacuum
leak at the air intake elbow):
"To test the AAR, disconnect its intake air hose from the AAR and plug it.
Take another piece of hose of the same ID (about 1/2" [12mm], about 6" in
length and attach it to the AAR. Then start the engine (the engine must be
cold). If you cover the hose (during warm-up), the engine should slow
down. After several minutes of operation, the vacuum should diminish and
eventually disappear almost completely.
"If the AAR does not close after a reasonable period (in cold weather,
considerable time may be required), stop the engine. Disconnect the the
electrical plug from the AAR. Using an ohmmeter, measure the resistance
between the two terminals on the AAR. The reading should be 30 ohms. If
the ohmmeter reads infinity or the resistance is considerable less than 30
ohms, replace the AAR."
Source: Type 2 68-79 Bentley, Section 10, Procedure 4.5, page 12
--
Jim Thompson
84 GL 1.9 "Gloria"
84 Westfalia 2.1 "Ole Putt"
73 K Ghia Coupe "Denise"
72 411 Station Wagon "Pug"
oldvolkshome@gmail.com
http://www.oldvolkshome.com
***********************************
On 9/26/07, Mike Rocket J Squirrel Elliott <camping.elliott@gmail.com>
wrote:
>
> So I'm looking at the Auxiliary Air Regulator in my 1.9L. It is supposed
> to bypass a little air around the throttle when cold and give the engine
> a little more pep. 12V from the fuel pump relay applied to its terminals
> causes that bypass to close after a couple minutes. At this point the
> engine can presumably get along fine without it.
>
> So Bentley's (24.28) gives us a simple test to see if the thing is
> working: start the engine and while cold, pinch the rubber hose. The
> rpms are supposed to drop.
>
> Well, they didn't so I moved to the next test: check to see if the AAR
> is getting 12V when the fuel pump is on, and it does.
>
> Then to the bench: you can look through the AAR and there is a disc
> blocking the passage, but there is a small hole in that disc which makes
> it easy to blow through. When 12V is applied to the AAR, the disc slowly
> rotates so the little hole is no longer visible after a minute or two
> and it's hard to blow through.
>
> So -- the AAR is fine, the hoses are fine, but pinching the hoses
> doesn't drop the rpms, as Bentley's say it should.
>
> --
>
> Mike "Rocket J Squirrel" Elliott
> 71 Type 2: the Wonderbus
> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
> 74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
> KG6RCR
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