Date: Fri, 30 Aug 2002 07:35:16 -0500
Reply-To: tmarciniak@WI.RR.COM
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tim Marciniak <tmarciniak@WI.RR.COM>
Subject: Re: Losing valve lash just after adjustment-why?
In-Reply-To: <OFDCAC5D18.A5F0A9E3-ON85256C25.00424C95@lvs.dupont.com>
Content-Type: text/plain; charset="us-ascii" ; format="flowed"
Jay,
That makes sense. The other thing I was expecting to hear after I
started up was some valve clatter noise thinking the .006 inch lash
would cause and there was no clatter at all---very quiet as before.
Bob at Boston Engine makes some remarks in his writings to be aware
of this noise as you tune between adjustments. I plan to readjust
the valves again this weekend, hope its not to soon but I really dont
like the way this engine is running.
Tim
>Run it for a while before re-adjusting the valves. Just long enough to get
>it warm, but not hot. This will allow the lifters to pump up a little and
>make adjusting easier (more defined zero-lash point). 20-50 oil does not
>flow very well unless it is really warm outside. The fact that the
>clearance is being lost tells me the lifters are continuing to pump up
>further. Probably a good sign!
> Jay
>
>
>
>
>Tim Marciniak <tmarciniak@WI.RR.COM>@gerry.vanagon.com> on 08/29/2002
>09:38:37 PM
>
>Please respond to tmarciniak@WI.RR.COM
>
>Sent by: Vanagon Mailing List <vanagon@gerry.vanagon.com>
>
>
>To: vanagon@GERRY.VANAGON.COM
>cc:
>Subject: Losing valve lash just after adjustment-why?
>
>
>Just did a compression test and two cylinders were low @ 100 and 106.
>Heads done about 20,000 miles ago by a VW mechanic (not dealer). Van
>has ran pretty well since them but lately I have developed a lumpy
>idle and low manifold vacuum (10-12). I researched everything I
>could find on the age old valve lifter issue including a call to Bob
>at Boston Engine were I purchased my heads from. Followed his
>instructions and adjusted the valves to .006 inch valve lash. I
>adjusted both intake and exhaust when engine cold. Just to be really
>thorough I rechecked them almost immediately after I adjusted them
>(did not rotate the crank yet) and I swear I was back to zero
>clearance so I readjusted again but did not recheck again cause i
>wanted to finish and the mosquitos were really bad last nite. I also
>checked all the valves for clearance before I adjusted and I could
>not get a .006 inch feeler gauge in on any of them--I am suspected my
>mechanic may of installed these heads the old way (preloading) and I
>am starting to see problems now. My question is why did I lose this
>.006 inch clearance just moments after I made the adjustment?
>
>I did start the engine up after adjusting all the valves and it ran
>pretty much the same, initially the manifold vacuum was about 14 but
>then dropped to 11-12 after the engine warmed up and idle was lumpy.
>
>Could it be the lifters are doing something strange? I am running
>20W-50 for the summer.
>
>Tim
>--
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