Date: Mon, 13 Aug 2001 16:30:27 -0400
Reply-To: Vanagon Man <puzerewski@MSN.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Vanagon Man <puzerewski@MSN.COM>
Subject: Re: Lifters Again
Basically your lifter is a cylinder with a plunger and spring with a ball in
it.
The whole idea is the system is to keep your valve train working properly
without the need for adjustments. If you have decided that 1 turn is what
you want to do, then chances are they never pumped up.
The zero lash is just that.......there is no give between the pushrod,
lifter and rocker arm.....any further turning of the screw if you watch
closely...one of two things will happen. either the valve spring will start
to compress meaning that your lifter is pumped, or the other scenario is
that you will see the pushrod moving towards the lifter, which means the
lifter is pumped.
Thus using this example, you can see that preloading does one of three
things. It takes the slack out of the valve train( mine are pumped, I use a
quarter turn, and if I begin to hear one, I run the valves, find the faulty
lifter, set it at .006, come back a couple of days and test it and set it at
zero or a quarter turn.) keeps your valves from closing all the way, or not
allowing your lifters to pump up.
I have tried the Bentley way, and know I totally follow Bob's method. It
works.
Adam P
81 westy (2 of them)
74 beetle
73 Transporter (new!!!!!!!) Total resto in progress
Vanagon Partsmobiles
----- Original Message -----
From: "Jay L Snyder" <Jay.L.Snyder@USA.DUPONT.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Monday, August 13, 2001 2:52 PM
Subject: Lifters Again
> I continue to have off and on lifter noise and would like a further
> explanation of Bob Donald's zero-lash method. I have new lifters
installed
> in my '85 1.9l. They have been in for about a year. I sometimes get
> noise on start-up, sometimes not. It is by far the worst thing about the
> whole vehicle. It sounds like you-know-what and is particularly annoying
> pulling out of a quiet campground. The performance is noticeably better
> when all is quiet. My oil pressure is low when hot, so I would expect
some
> lifter noise when pulling off the freeway and coming to an idle. This I
can
> understand. I've seen it with Corvairs. (The also went from the factory
2
> turns to about 1/4 turn in the real world--but never zero lash.)
> I realize that at zero lash the lifter can fully expand and purge any air
> bound in the lifter. Can you just leave it this way or do you then go
back
> and pre-load some amount of turns?
> I am running at around 1 turn. Unless I am missing something, less
> pre-load would be horrible at a hot-idle. I suspect my lifters are
> partially collapsing when hot because I get a rough idle and it will
> sometimes stall--really annoying when trying to maneuver into a campsite
or
> parking lot.
> Is this engine going to be like this until I rebuild? I am guessing
better
> oil pressure help all of this. Since the lifters are new, I don't think
> MMO will help. I actually tried it once before, but noticed a slight oil
> pressure drop. I may put some in right before my next oil change and then
> get it out.
> Any first hand experience would be appreciated.
>
> Jay '85 Westy (The Hindenburg)
>
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