Date: Sun, 8 Jun 2003 21:47:17 -0400
Reply-To: EMZ <vw4x4@EWOK.VANAGON.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: EMZ <vw4x4@EWOK.VANAGON.COM>
Subject: Re: valve cover and vacuum question -1.8 Gas conversion
In-Reply-To: <00a701c32e19$11a3e680$6b2b6e89@sonyf3ks1bhv4d>
Content-Type: TEXT/PLAIN; charset=US-ASCII
Matt,
There is a very simply fix to this. The 1988-1992 Jetta/Golf engine
had a nice ungrade to the crank case ventalation. It uses a large plastic
disc like PCV device that plugs into the valve cover and then has a hose
that goes directly to the intake. Check one of these out, in a junk yard.
Eric 86-VW4x4
vw4x4@fyi.net 86-SS Syncro
Pittsburgh, PA USA 1936-Chrysler
92-Jetta GWC
www.fyi.net/~vw4x4/vw4x4.htm
On Sun, 8 Jun 2003, Matt Ratto wrote:
> Hi all,
>
> I've been driving my 1982 Westy, into which I installed a 1.8L gas motor
> from an 1986 Golf (engine code GX.) It runs OK, but has poor mileage, smells
> like it's running rich (but the plugs look OK,) and has a kind of loping
> idle. I've screwed with the mixture, timing, and idle bypass until I'm blue
> in the face but none of these seem to make much of a difference. I have
> noticed that I can't get it to run very well if I time it to what the manual
> says is correct - approx. 8 BTDC. (Currently it's at about 8 ATDC.) For all
> of these reasons, I assumed I had a vacuum leak somewhere, but after
> spraying carb cleaner everywhere I can't find any leak.
>
> The other day I was thinking about this problem and I realized that because
> of the way I had installed the engine (and removed a bunch of exhaust
> equipment) the vaccuum line that connects to the top of the valve cover was
> vented directly into the CIS air box (below the filter.) This is in addition
> to another line also connected to the same place on the top of the valve
> cover that connects into the intake manifold. (I hope that makes sense.)
>
> In the interest of science, I disconnected the line running to the air box
> and blocked it up with a piece of (you guessed it) duct tape. The car
> started running differently, but before I could play with the timing and the
> rest, I started hearing a funny whining coming from the crankcase. I
> realized that since this engine does not have a separate crankcase
> ventilation system (as far as I know) with the valve cover line blocked I
> was probably creating a lot of pressure in the crankcase. Since this is
> probably A Bad Thing(tm) I immediately pulled off the duct tape.
>
> So here's my question (for those of you who have read this far): Could the
> way I've connected the valve cover line be causing a lack of vacuum and
> making the car run like it has a vacuum leak? If so, how should I connect
> this line as to provide vacuum but not overpressure the crankcase?
> Alternatively, is my hypothesis completely wrong, my troubleshooting totally
> incorrect, and I should buy a honda with the hood welded shut?
>
> any responses are appreciated,
>
> Matt
> -------------------------------------
> Matt Ratto
> Ph.D. Candidate
> University of California, San Diego
> mratto@ucsd.edu
> http://communication.ucsd.edu/mratto
> --------------------------------------
>
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