lifter tick

Mark R speedracer.mark at gmail.com
Thu Jul 31 08:58:22 PDT 2008


The "tick" is the camshaft (or rocker arm in something like a small block
chevy) "hitting" the top of the lifter.  In other words, the lobe doesn't
always remain in contact with the "top" of the lifter as it should (with the
obvious thin coating of oil in between).  If you picture the "tick" as a
hammering type of action, you'll envision what's going on.  The wear is the
surfaces of top(s) of the lifter(s) and the cam lobe(s).

Why does this occur?  History- lifters used to be manually adjusted and the
"lash" was set by shims or some other adjusting mechanisms.  This was a
maintenance item and required packaging so that this was possible to
routinely adjust.  Also, with tighter emissions regulations, having it only
adjusted periodically meant that all other time, the timing wasn't optimal.
This is especially troublesome in a lean-burn emissions configuration.

The fix which allowed for tighter engine packaging, improved performance
over time, and improved emissions- lifters which self-adjusted.  they do
this by being "pumped up" (thing of them as being elongated) by oil pressure
(and volume).  Hence the term "hydraulic lifters."

If they don't "pump up" as designed, the lash becomes greater, wear
increases, and valve timing is off.  Again, many cars can go a long time in
this state before anything catastrophic occurs.  Respectfully, I believe if
there's a tick, there IS increased wear occurring versus a valvetrain which
isn't ticking.  I fully agree that for a lot of people and budgets, it might
not be enough wear for a lot of concern.... which is what I suspect Grant's
comment really meant.

Hope this helped!
Mark Rosenkrantz

On Thu, Jul 31, 2008 at 11:25 AM, <jlagnese at massed.net> wrote:

>  I was under the impression that lifter tick, caused by hydraulic lifters
> not full of oil, simply decreased efficiency since the valves were not
> opening fully.
>
> So where is the wear? The top or inside of the lifter? The cam? Anytime
> there is not enough oil someplace, things do wear!
>
> John
> ---- Original message ----
>
> *Date:* Thu, 31 Jul 2008 10:39:27 -0400
> *From:* "Mark R" <speedracer.mark at gmail.com>
> *Subject:* Re: lifter tick
> *To:* "Grant Lenahan" <glenahan at vfemail.net>
> *Cc:* quattro at audifans.com
> >I respectfully disagree with Grant. Lifter tick DOES increase wear. That
> >said, Audis seem to tolerate it for a LONG time, so it might not be worth
> >the expense and trouble of replacing the lifters. In other words, the harm
> >is typically minimal, but it is there.
> >
> >If you fixed it with different oil or a solvent... then it's fixed.
> >Hydraulic lifter tick is caused by "crud" (deposits) in the lifter(s), low
> >oil pressure, incorrect weight of oil, etc. The first step is always to
> >either try a solvent, switch oils (weight, type, brand), oil filter brand,
> >etc. If that solves the problem, then there's no problem remaining! =)
> >
> >Cheers!
> >Mark Rosenkrantz
> >
> >On Thu, Jul 31, 2008 at 8:01 AM, Grant Lenahan <glenahan at vfemail.net>
> wrote:
> >
> >> ignore it - it does no harm
> >>
> >> On Jul 30, 2008, at 10:09 PM, Rick Cone wrote:
> >>
> >> > My 89 Audi 200 has a rather noisy lifter tick. I "fixed" it with a
> >> > quart of Lucas, but what is the real fix? Is there any adjustment
> >> > in the valvetrain of these things?
> >> > Rick A. Cone
> >> >
> >> >
> >> >
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