Date: Wed, 29 Aug 2001 05:26:02 -0500
Reply-To: Max Wellhouse <maxjoyce@IPA.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Max Wellhouse <maxjoyce@IPA.NET>
Subject: Re: valve lash adjustment
Content-Type: text/plain; charset="iso-8859-1"
My guess is that you don't have all the air out of the spongie ones yet.
BOB?
dm&fs
----- Original Message -----
From: "Scott G. Terry" <sgterry@ENGINEERING.UCSB.EDU>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, August 28, 2001 5:08 PM
Subject: Re: valve lash adjustment
> Jay et al.,
>
> Your original post describing your success with the Boston Bob valve lash
> adjustment inspired me to give it a try.
>
> I'm not sure if I understood the approach and did it right, but here's
what
> I did (I'm new to wrenching Vanagons and not a very experienced mechanic
in
> general):
>
> Saturday I set the valve lash clearance to 0.005" cold. You all would
> laugh at how long it took me to do this! The funniest part was me trying
> to turn the crankshaft pulley by hand to get to top dead center (tdc). I
> expected this to be difficult but found it to be impossible. Figured I
> would reduce the compression by pulling the spark plugs. As I pulled the
> third plug I suddenly remembered I had parked the van in 1st gear. Duh.
> As you can imagine, it was quite a bit easier to turn the engine with the
> tranny in neutral. After popping off the distributor cap, I used the
rotor
> position and the tdc notch in the crankshaft pulley to locate tdc for the
> #1 cylinder, set the rocker clearances for #1, then turned the pulley 180
> degrees (clockwise) to get #4 tdc, set #4 clearances, and repeated for #3
> and #2 cylinders. I think I read the Boston Bob procedure called for an
> initial 0.006" clearance but the closest feeler gauge I had was 0.005.
>
> Drove the van on a short errand in town on Sunday. A fair amount of
lifter
> noise but not really alarming. It was my understanding that the lifters
> would expel any trapped air and "pump up" after a some driving which could
> take up to a week.
>
> This morning I decided to drive the van to work to give the lifters more
> exercise. Now that I was on the highway I realized that she was way low
on
> power! I exited the highway and returned home. What have I done to my
> van, I thought... I decided to perform the second part of the Boston Bob
> adjustment immediately. I couldn't imagine driving the engine like that
> anymore. This round of valve adjustments went way faster. I found that
> some of the lifters had pumped up as evidenced by the absence of any
> clearance at tdc. I went through and adjusted each valve to zero
clearance
> plus a quarter turn tightening of the adjusting screw, slapped the valve
> covers back on, and fired her up. She purred. Idled rock steady at 950
> rpm and no lifter noise. Drove to work with full power. I'm going to
> measure the manifold vacuum at idle and see if there has been any
> improvement.
>
> As I adjusted the valves for each cylinder a second time I could feel a
> difference in the lifter action as I made the final 1/4 turn of each adj.
> screw. Some of the lifters felt very firm, others felt spongy. What does
> this mean?
>
> Scott
> '85 Westy "Pearl"
> Santa Barbara, CA
>
> >From: Jay L Snyder <Jay.L.Snyder@USA.DUPONT.COM>
> >Subject: Valve Adjustment
> >Excellent results so far with the zero-lash valve adjustment. I want to
go
> >to about 1/4 turn to see if I can quiet the valves completely. I get
some
> >initial noise, but no clacking as before and they quickly pump up and are
> >quiet from then on, even when hot coming off the interstate. Much
better
> >low end grunt and cold starts. I would like to pull the valve covers
and
> >check to see if any of the adjustments has changed since I last adjusted
> >them (any lifters pump up further?). Anyone have a good solution to
> >marking the 180 degree spot opposite the TDC notch? I have a scratch
mark
> >drawn, but I am not sure it is accurate. There isn't much room there
with
> >the triple pulley. Maybe I could put masking tape on it and mark off in
> >inches? It would be nice to have a total advance mark too, to check the
> >total distributor advance. And maybe a 5 degrees BTDC mark.....
> > Jay ('85 Westy)
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