Cory Dunkle

I have a 302 ('86 block, 28oz imbalance) with '65 289 heads (round pushrod
holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic flat
tappet cam.

My #8 intake valve makes a ticking/tapping noise. It sounds a lot like when
a rocker arm is too loose, except perhaps a bit of a deeper tone. With the
engine running and the valve cover off the noise is present. When I push the
rocker arm (at the valve tip) toward the front of the motor, the noise goes
away and the motor doesn't make any noise. When I let go it will stay silent
for a few seconds, then start making the nosie again. If I push the rocker
arm (at the valve tip) toward the back of the motor, it will also make the
noise. The motor does not make this noise when cold (if it does, it is very
faint), only after running for 5-10 minutes to get up to temperature.

This noise is not present when turning the motor over by hand. I checked for
clearance issues between the rails on the rocker arm and the retainer, there
are none. I checekd to ensure the rocker arm slot is long enough and is not
binding on the stud, it is not. There is no sign of abnormal wear on the
valve tip or the rocker arm. The valve spring and damper appear to be intact
and not binding. The damper does not appear to be hanging or binding on the
spring.

If anyone has any thoughts on what this may be I'd appreciate it.

Cory

 

tom

adjust your valves to zero lash, plus 1/4 turn. this should eliminate your
problem
"Cory Dunkle" <cdnews@comcast.net> wrote in message
news:i6GdnYahrvGieavfRVn-og@comcast.com...
> I have a 302 ('86 block, 28oz imbalance) with '65 289 heads (round pushrod
> holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic flat
> tappet cam.
>
> My #8 intake valve makes a ticking/tapping noise. It sounds a lot like
when
> a rocker arm is too loose, except perhaps a bit of a deeper tone. With the
> engine running and the valve cover off the noise is present. When I push
the
> rocker arm (at the valve tip) toward the front of the motor, the noise
goes
> away and the motor doesn't make any noise. When I let go it will stay
silent
> for a few seconds, then start making the nosie again. If I push the rocker
> arm (at the valve tip) toward the back of the motor, it will also make the
> noise. The motor does not make this noise when cold (if it does, it is
very
> faint), only after running for 5-10 minutes to get up to temperature.
>
> This noise is not present when turning the motor over by hand. I checked
for
> clearance issues between the rails on the rocker arm and the retainer,
there
> are none. I checekd to ensure the rocker arm slot is long enough and is
not
> binding on the stud, it is not. There is no sign of abnormal wear on the
> valve tip or the rocker arm. The valve spring and damper appear to be
intact
> and not binding. The damper does not appear to be hanging or binding on
the
> spring.
>
> If anyone has any thoughts on what this may be I'd appreciate it.
>
> Cory
>
>

Cory Dunkle

Unfortunately that doesn't cure it. I've tried tightening it even more
(slowly with engien running until it runs rough) and it doesn't do it. The
heads don't have a whole lot of miles on them... I got them second hand but
they did not have many miles on them when I got them, and I've only put
18,000 miles on them. They should have less than 25,000 miles. All the other
rockers are quiet with adjusting to zero+1/4 turn.

I'm wondering if maybe the valve guide on that cylinder could be bad/worn on
that valve, maybe letting the valve rock a little in the guide. The noise is
a lower pitched noise than typical rocker noise. Don't know if that tells
you anything though.

Cory

"tom" <tjctransport@optonline.net> wrote in message
news:tRGZd.4201$iZ7.523@fe10.lga...
> adjust your valves to zero lash, plus 1/4 turn. this should eliminate your
> problem
> "Cory Dunkle" <cdnews@comcast.net> wrote in message
> news:i6GdnYahrvGieavfRVn-og@comcast.com...
> > I have a 302 ('86 block, 28oz imbalance) with '65 289 heads (round
pushrod
> > holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic flat
> > tappet cam.
> >
> > My #8 intake valve makes a ticking/tapping noise. It sounds a lot like
> when
> > a rocker arm is too loose, except perhaps a bit of a deeper tone. With
the
> > engine running and the valve cover off the noise is present. When I push
> the
> > rocker arm (at the valve tip) toward the front of the motor, the noise
> goes
> > away and the motor doesn't make any noise. When I let go it will stay
> silent
> > for a few seconds, then start making the nosie again. If I push the
rocker
> > arm (at the valve tip) toward the back of the motor, it will also make
the
> > noise. The motor does not make this noise when cold (if it does, it is
> very
> > faint), only after running for 5-10 minutes to get up to temperature.
> >
> > This noise is not present when turning the motor over by hand. I checked
> for
> > clearance issues between the rails on the rocker arm and the retainer,
> there
> > are none. I checekd to ensure the rocker arm slot is long enough and is
> not
> > binding on the stud, it is not. There is no sign of abnormal wear on the
> > valve tip or the rocker arm. The valve spring and damper appear to be
> intact
> > and not binding. The damper does not appear to be hanging or binding on
> the
> > spring.
> >
> > If anyone has any thoughts on what this may be I'd appreciate it.
> >
> > Cory
> >
> >
>
>

tom

when you go to zero plus 1/4, does the noise go away for a bit and then come
back?? if so, than you probably have a bad lifter
"Cory Dunkle" <cdnews@comcast.net> wrote in message
news:F_CdnTG1bJjKx6rfRVn-ow@comcast.com...
> Unfortunately that doesn't cure it. I've tried tightening it even more
> (slowly with engien running until it runs rough) and it doesn't do it. The
> heads don't have a whole lot of miles on them... I got them second hand
but
> they did not have many miles on them when I got them, and I've only put
> 18,000 miles on them. They should have less than 25,000 miles. All the
other
> rockers are quiet with adjusting to zero+1/4 turn.
>
> I'm wondering if maybe the valve guide on that cylinder could be bad/worn
on
> that valve, maybe letting the valve rock a little in the guide. The noise
is
> a lower pitched noise than typical rocker noise. Don't know if that tells
> you anything though.
>
> Cory
>
> "tom" <tjctransport@optonline.net> wrote in message
> news:tRGZd.4201$iZ7.523@fe10.lga...
> > adjust your valves to zero lash, plus 1/4 turn. this should eliminate
your
> > problem
> > "Cory Dunkle" <cdnews@comcast.net> wrote in message
> > news:i6GdnYahrvGieavfRVn-og@comcast.com...
> > > I have a 302 ('86 block, 28oz imbalance) with '65 289 heads (round
> pushrod
> > > holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic flat
> > > tappet cam.
> > >
> > > My #8 intake valve makes a ticking/tapping noise. It sounds a lot like
> > when
> > > a rocker arm is too loose, except perhaps a bit of a deeper tone. With
> the
> > > engine running and the valve cover off the noise is present. When I
push
> > the
> > > rocker arm (at the valve tip) toward the front of the motor, the noise
> > goes
> > > away and the motor doesn't make any noise. When I let go it will stay
> > silent
> > > for a few seconds, then start making the nosie again. If I push the
> rocker
> > > arm (at the valve tip) toward the back of the motor, it will also make
> the
> > > noise. The motor does not make this noise when cold (if it does, it is
> > very
> > > faint), only after running for 5-10 minutes to get up to temperature.
> > >
> > > This noise is not present when turning the motor over by hand. I
checked
> > for
> > > clearance issues between the rails on the rocker arm and the retainer,
> > there
> > > are none. I checekd to ensure the rocker arm slot is long enough and
is
> > not
> > > binding on the stud, it is not. There is no sign of abnormal wear on
the
> > > valve tip or the rocker arm. The valve spring and damper appear to be
> > intact
> > > and not binding. The damper does not appear to be hanging or binding
on
> > the
> > > spring.
> > >
> > > If anyone has any thoughts on what this may be I'd appreciate it.
> > >
> > > Cory
> > >
> > >
> >
> >
>
>

Cory Dunkle

I don't remember for sure, but I don't believe it does. I'll test that as
you mention though, and see if the noise goes away for a second. It would be
nice if it was something as cheap and easy as a bad lifter. I kinda doubt it
though, as I don't imagine moving the rocker that little bit has much affect
on the lifter. The noise goes away if I push hard on the side of the valve
spring and retainer, not touching the rocker arm.

Cory

"tom" <tjctransport@optonline.net> wrote in message
news:x1LZd.23166$W62.10875@fe09.lga...
> when you go to zero plus 1/4, does the noise go away for a bit and then
come
> back?? if so, than you probably have a bad lifter
> "Cory Dunkle" <cdnews@comcast.net> wrote in message
> news:F_CdnTG1bJjKx6rfRVn-ow@comcast.com...
> > Unfortunately that doesn't cure it. I've tried tightening it even more
> > (slowly with engien running until it runs rough) and it doesn't do it.
The
> > heads don't have a whole lot of miles on them... I got them second hand
> but
> > they did not have many miles on them when I got them, and I've only put
> > 18,000 miles on them. They should have less than 25,000 miles. All the
> other
> > rockers are quiet with adjusting to zero+1/4 turn.
> >
> > I'm wondering if maybe the valve guide on that cylinder could be
bad/worn
> on
> > that valve, maybe letting the valve rock a little in the guide. The
noise
> is
> > a lower pitched noise than typical rocker noise. Don't know if that
tells
> > you anything though.
> >
> > Cory
> >
> > "tom" <tjctransport@optonline.net> wrote in message
> > news:tRGZd.4201$iZ7.523@fe10.lga...
> > > adjust your valves to zero lash, plus 1/4 turn. this should eliminate
> your
> > > problem
> > > "Cory Dunkle" <cdnews@comcast.net> wrote in message
> > > news:i6GdnYahrvGieavfRVn-og@comcast.com...
> > > > I have a 302 ('86 block, 28oz imbalance) with '65 289 heads (round
> > pushrod
> > > > holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic
flat
> > > > tappet cam.
> > > >
> > > > My #8 intake valve makes a ticking/tapping noise. It sounds a lot
like
> > > when
> > > > a rocker arm is too loose, except perhaps a bit of a deeper tone.
With
> > the
> > > > engine running and the valve cover off the noise is present. When I
> push
> > > the
> > > > rocker arm (at the valve tip) toward the front of the motor, the
noise
> > > goes
> > > > away and the motor doesn't make any noise. When I let go it will
stay
> > > silent
> > > > for a few seconds, then start making the nosie again. If I push the
> > rocker
> > > > arm (at the valve tip) toward the back of the motor, it will also
make
> > the
> > > > noise. The motor does not make this noise when cold (if it does, it
is
> > > very
> > > > faint), only after running for 5-10 minutes to get up to
temperature.
> > > >
> > > > This noise is not present when turning the motor over by hand. I
> checked
> > > for
> > > > clearance issues between the rails on the rocker arm and the
retainer,
> > > there
> > > > are none. I checekd to ensure the rocker arm slot is long enough and
> is
> > > not
> > > > binding on the stud, it is not. There is no sign of abnormal wear on
> the
> > > > valve tip or the rocker arm. The valve spring and damper appear to
be
> > > intact
> > > > and not binding. The damper does not appear to be hanging or binding
> on
> > > the
> > > > spring.
> > > >
> > > > If anyone has any thoughts on what this may be I'd appreciate it.
> > > >
> > > > Cory
> > > >
> > > >
> > >
> > >
> >
> >
>
>

pick one

Instead of constantly just tightening the lifter which does nothing but limit
its job why don't you measure the rocker travel. Do some real diagnosis. Install
a dial indicator on a good rocker and measure the travel while slowly turning
over the engine. Then do the same on the suspect rocker. Make sure that if the
suspect bad rocker or cam lobe is a intake you put the dial indicator on a
intake, if it is an exhaust, measure an exhaust. Your looking for the same
travel. That will tell you if the cam lobe is worn down. Hell even a cheap
Haynes manual talks about measuring cam lobe lift.


"Cory Dunkle" <cdnews@comcast.net> wrote in message
news:u62dnbvXPvaoOKrfRVn-1w@comcast.com...
>I don't remember for sure, but I don't believe it does. I'll test that as
> you mention though, and see if the noise goes away for a second. It would be
> nice if it was something as cheap and easy as a bad lifter. I kinda doubt it
> though, as I don't imagine moving the rocker that little bit has much affect
> on the lifter. The noise goes away if I push hard on the side of the valve
> spring and retainer, not touching the rocker arm.
>
> Cory
>
> "tom" <tjctransport@optonline.net> wrote in message
> news:x1LZd.23166$W62.10875@fe09.lga...
>> when you go to zero plus 1/4, does the noise go away for a bit and then
> come
>> back?? if so, than you probably have a bad lifter
>> "Cory Dunkle" <cdnews@comcast.net> wrote in message
>> news:F_CdnTG1bJjKx6rfRVn-ow@comcast.com...
>> > Unfortunately that doesn't cure it. I've tried tightening it even more
>> > (slowly with engien running until it runs rough) and it doesn't do it.
> The
>> > heads don't have a whole lot of miles on them... I got them second hand
>> but
>> > they did not have many miles on them when I got them, and I've only put
>> > 18,000 miles on them. They should have less than 25,000 miles. All the
>> other
>> > rockers are quiet with adjusting to zero+1/4 turn.
>> >
>> > I'm wondering if maybe the valve guide on that cylinder could be
> bad/worn
>> on
>> > that valve, maybe letting the valve rock a little in the guide. The
> noise
>> is
>> > a lower pitched noise than typical rocker noise. Don't know if that
> tells
>> > you anything though.
>> >
>> > Cory
>> >
>> > "tom" <tjctransport@optonline.net> wrote in message
>> > news:tRGZd.4201$iZ7.523@fe10.lga...
>> > > adjust your valves to zero lash, plus 1/4 turn. this should eliminate
>> your
>> > > problem
>> > > "Cory Dunkle" <cdnews@comcast.net> wrote in message
>> > > news:i6GdnYahrvGieavfRVn-og@comcast.com...
>> > > > I have a 302 ('86 block, 28oz imbalance) with '65 289 heads (round
>> > pushrod
>> > > > holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic
> flat
>> > > > tappet cam.
>> > > >
>> > > > My #8 intake valve makes a ticking/tapping noise. It sounds a lot
> like
>> > > when
>> > > > a rocker arm is too loose, except perhaps a bit of a deeper tone.
> With
>> > the
>> > > > engine running and the valve cover off the noise is present. When I
>> push
>> > > the
>> > > > rocker arm (at the valve tip) toward the front of the motor, the
> noise
>> > > goes
>> > > > away and the motor doesn't make any noise. When I let go it will
> stay
>> > > silent
>> > > > for a few seconds, then start making the nosie again. If I push the
>> > rocker
>> > > > arm (at the valve tip) toward the back of the motor, it will also
> make
>> > the
>> > > > noise. The motor does not make this noise when cold (if it does, it
> is
>> > > very
>> > > > faint), only after running for 5-10 minutes to get up to
> temperature.
>> > > >
>> > > > This noise is not present when turning the motor over by hand. I
>> checked
>> > > for
>> > > > clearance issues between the rails on the rocker arm and the
> retainer,
>> > > there
>> > > > are none. I checekd to ensure the rocker arm slot is long enough and
>> is
>> > > not
>> > > > binding on the stud, it is not. There is no sign of abnormal wear on
>> the
>> > > > valve tip or the rocker arm. The valve spring and damper appear to
> be
>> > > intact
>> > > > and not binding. The damper does not appear to be hanging or binding
>> on
>> > > the
>> > > > spring.
>> > > >
>> > > > If anyone has any thoughts on what this may be I'd appreciate it.
>> > > >
>> > > > Cory
>> > > >
>> > > >
>> > >
>> > >
>> >
>> >
>>
>>
>
>

Cory Dunkle

I remember now why I stopped reading and posting to this group. Too many
smart-asses like you being rude. I think it's clear I've done a little more
than just sit there tightening down on the rocker (can't tighten a lifter,
except perhaps with a different spring, smart-ass).

In any case, while measuring the travel may be worthwhile, I don't
understand how that may cause a ticking/tapping that would stop when
applying pressure on the side of the valve. If the cam lobe were worn that
should only result in less valve lift. Adjusting the rocker properly should
ensure there is no noise as there is no slack anywhere from camshaft to
valve. So, if you don't mind, I'm curious as to how a slightly worn cam lobe
would make the rather loud noise my engien is making.

For what it's worth the motor only has 18,000 miles on it and was properly
broken in, and looking down the head all rockers appear to have the same
travel (I know that doesn't necessarily mean much, but I've seen engines
with wiped cam lobes and it was obvious to me that those particular valves
were not opening as far as the others).

Cory

"pick one" <try again!> wrote in message
news:CNCdnSadv78ON6rfRVn-sA@comcast.com...
>
> Instead of constantly just tightening the lifter which does nothing but
limit
> its job why don't you measure the rocker travel. Do some real diagnosis.
Install
> a dial indicator on a good rocker and measure the travel while slowly
turning
> over the engine. Then do the same on the suspect rocker. Make sure that if
the
> suspect bad rocker or cam lobe is a intake you put the dial indicator on a
> intake, if it is an exhaust, measure an exhaust. Your looking for the same
> travel. That will tell you if the cam lobe is worn down. Hell even a cheap
> Haynes manual talks about measuring cam lobe lift.
>
>
> "Cory Dunkle" <cdnews@comcast.net> wrote in message
> news:u62dnbvXPvaoOKrfRVn-1w@comcast.com...
> >I don't remember for sure, but I don't believe it does. I'll test that as
> > you mention though, and see if the noise goes away for a second. It
would be
> > nice if it was something as cheap and easy as a bad lifter. I kinda
doubt it
> > though, as I don't imagine moving the rocker that little bit has much
affect
> > on the lifter. The noise goes away if I push hard on the side of the
valve
> > spring and retainer, not touching the rocker arm.
> >
> > Cory
> >
> > "tom" <tjctransport@optonline.net> wrote in message
> > news:x1LZd.23166$W62.10875@fe09.lga...
> >> when you go to zero plus 1/4, does the noise go away for a bit and then
> > come
> >> back?? if so, than you probably have a bad lifter
> >> "Cory Dunkle" <cdnews@comcast.net> wrote in message
> >> news:F_CdnTG1bJjKx6rfRVn-ow@comcast.com...
> >> > Unfortunately that doesn't cure it. I've tried tightening it even
more
> >> > (slowly with engien running until it runs rough) and it doesn't do
it.
> > The
> >> > heads don't have a whole lot of miles on them... I got them second
hand
> >> but
> >> > they did not have many miles on them when I got them, and I've only
put
> >> > 18,000 miles on them. They should have less than 25,000 miles. All
the
> >> other
> >> > rockers are quiet with adjusting to zero+1/4 turn.
> >> >
> >> > I'm wondering if maybe the valve guide on that cylinder could be
> > bad/worn
> >> on
> >> > that valve, maybe letting the valve rock a little in the guide. The
> > noise
> >> is
> >> > a lower pitched noise than typical rocker noise. Don't know if that
> > tells
> >> > you anything though.
> >> >
> >> > Cory
> >> >
> >> > "tom" <tjctransport@optonline.net> wrote in message
> >> > news:tRGZd.4201$iZ7.523@fe10.lga...
> >> > > adjust your valves to zero lash, plus 1/4 turn. this should
eliminate
> >> your
> >> > > problem
> >> > > "Cory Dunkle" <cdnews@comcast.net> wrote in message
> >> > > news:i6GdnYahrvGieavfRVn-og@comcast.com...
> >> > > > I have a 302 ('86 block, 28oz imbalance) with '65 289 heads
(round
> >> > pushrod
> >> > > > holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic
> > flat
> >> > > > tappet cam.
> >> > > >
> >> > > > My #8 intake valve makes a ticking/tapping noise. It sounds a lot
> > like
> >> > > when
> >> > > > a rocker arm is too loose, except perhaps a bit of a deeper tone.
> > With
> >> > the
> >> > > > engine running and the valve cover off the noise is present. When
I
> >> push
> >> > > the
> >> > > > rocker arm (at the valve tip) toward the front of the motor, the
> > noise
> >> > > goes
> >> > > > away and the motor doesn't make any noise. When I let go it will
> > stay
> >> > > silent
> >> > > > for a few seconds, then start making the nosie again. If I push
the
> >> > rocker
> >> > > > arm (at the valve tip) toward the back of the motor, it will also
> > make
> >> > the
> >> > > > noise. The motor does not make this noise when cold (if it does,
it
> > is
> >> > > very
> >> > > > faint), only after running for 5-10 minutes to get up to
> > temperature.
> >> > > >
> >> > > > This noise is not present when turning the motor over by hand. I
> >> checked
> >> > > for
> >> > > > clearance issues between the rails on the rocker arm and the
> > retainer,
> >> > > there
> >> > > > are none. I checekd to ensure the rocker arm slot is long enough
and
> >> is
> >> > > not
> >> > > > binding on the stud, it is not. There is no sign of abnormal wear
on
> >> the
> >> > > > valve tip or the rocker arm. The valve spring and damper appear
to
> > be
> >> > > intact
> >> > > > and not binding. The damper does not appear to be hanging or
binding
> >> on
> >> > > the
> >> > > > spring.
> >> > > >
> >> > > > If anyone has any thoughts on what this may be I'd appreciate it.
> >> > > >
> >> > > > Cory
> >> > > >
> >> > > >
> >> > >
> >> > >
> >> >
> >> >
> >>
> >>
> >
> >
>
>

pick one

"Cory Dunkle" <cdnews@comcast.net> wrote in message
news:C5Odnfu9xOE606XfRVn-rA@comcast.com...
>I remember now why I stopped reading and posting to this group. Too many
> smart-asses like you being rude. I think it's clear I've done a little more
> than just sit there tightening down on the rocker (can't tighten a lifter,
> except perhaps with a different spring, smart-ass).
>

You can over tighten a lifter till the internal spring is collapsed, now it's a
solid lifter. Once a lifter is adjusted it should never need adjusting.

> In any case, while measuring the travel may be worthwhile, I don't
> understand how that may cause a ticking/tapping that would stop when
> applying pressure on the side of the valve. If the cam lobe were worn that
> should only result in less valve lift. Adjusting the rocker properly should
> ensure there is no noise as there is no slack anywhere from camshaft to
> valve. So, if you don't mind, I'm curious as to how a slightly worn cam lobe
> would make the rather loud noise my engien is making.
>
In side your type of lifter is a plunger held up by a spring. There are two oil
passage ways. there is also a check valve. The job of the lifter is to provide
oil supply to the rocker through the lifter, that is done with the plunger. This
is what happens. When the lifter is on the base of the cam lobe ( valve closed )
the oil passage on the side ( notice the hole is also in a grove ) of the lifter
is feed with oil from the oil pump ( the lifter is also a valve of sorts ). This
fills the space beneath the plunger. As the cam rotates and pushes the lifter up
it's bore the hole in the side of the lifter moves up ( duh ). Now the lifter
acts as a valve, the hole and grove is past the feed hole in the block, so the
oil passage is closed. The space beneath the plunger is now full. As the lifter
continues up it tries to push against the push rod which at this point the oil
pressure in the lifter combined with the spring over comes the pressure of the
valve spring. As the lifter gets towards the top of its travel the valve spring
is near it's fully compressed state, because of this spring pressure of the
valve over comes the oil pressure and spring pressure in the space below the
plunger moving the plunger down into the lifter. The oil pressure in side the
lifter raises up enough to open the check valve and that small amount of oil is
now forced into the push rod. As the cam rotates to the down slope of the lobe
the spring pressure from the valve pushes the lifter down into its bore. As the
valve closes the spring pressure becomes less than the spring pressure in side
the lifter, so now the plunger moves up in it's bore. Then the cycle starts over
again. Eventually the push rod gets full so any extra oil gets pushed out lubing
the rest of the valve train. That is why lifters always tick for a while when
new ones are installed and why there is always a delay for oil squirting out the
top of the push rod. That being said you can see why just tightening the valve
does nothing but cause more problems. You run the risk of collapsing the lifter,
that will starve the rest of the valve train of oil.


> For what it's worth the motor only has 18,000 miles on it and was properly
> broken in, and looking down the head all rockers appear to have the same
> travel (I know that doesn't necessarily mean much, but I've seen engines
> with wiped cam lobes and it was obvious to me that those particular valves
> were not opening as far as the others).
>

It only takes a few thousands to make lifter noise. Didnt you recently say you
over heated this engine by running it with no coolant? Thats all it takes to
destroy a lifter.

> Cory
>
> "pick one" <try again!> wrote in message
> news:CNCdnSadv78ON6rfRVn-sA@comcast.com...
>>
>> Instead of constantly just tightening the lifter which does nothing but
> limit
>> its job why don't you measure the rocker travel. Do some real diagnosis.
> Install
>> a dial indicator on a good rocker and measure the travel while slowly
> turning
>> over the engine. Then do the same on the suspect rocker. Make sure that if
> the
>> suspect bad rocker or cam lobe is a intake you put the dial indicator on a
>> intake, if it is an exhaust, measure an exhaust. Your looking for the same
>> travel. That will tell you if the cam lobe is worn down. Hell even a cheap
>> Haynes manual talks about measuring cam lobe lift.
>>
>>
>> "Cory Dunkle" <cdnews@comcast.net> wrote in message
>> news:u62dnbvXPvaoOKrfRVn-1w@comcast.com...
>> >I don't remember for sure, but I don't believe it does. I'll test that as
>> > you mention though, and see if the noise goes away for a second. It
> would be
>> > nice if it was something as cheap and easy as a bad lifter. I kinda
> doubt it
>> > though, as I don't imagine moving the rocker that little bit has much
> affect
>> > on the lifter. The noise goes away if I push hard on the side of the
> valve
>> > spring and retainer, not touching the rocker arm.
>> >
>> > Cory
>> >
>> > "tom" <tjctransport@optonline.net> wrote in message
>> > news:x1LZd.23166$W62.10875@fe09.lga...
>> >> when you go to zero plus 1/4, does the noise go away for a bit and then
>> > come
>> >> back?? if so, than you probably have a bad lifter
>> >> "Cory Dunkle" <cdnews@comcast.net> wrote in message
>> >> news:F_CdnTG1bJjKx6rfRVn-ow@comcast.com...
>> >> > Unfortunately that doesn't cure it. I've tried tightening it even
> more
>> >> > (slowly with engien running until it runs rough) and it doesn't do
> it.
>> > The
>> >> > heads don't have a whole lot of miles on them... I got them second
> hand
>> >> but
>> >> > they did not have many miles on them when I got them, and I've only
> put
>> >> > 18,000 miles on them. They should have less than 25,000 miles. All
> the
>> >> other
>> >> > rockers are quiet with adjusting to zero+1/4 turn.
>> >> >
>> >> > I'm wondering if maybe the valve guide on that cylinder could be
>> > bad/worn
>> >> on
>> >> > that valve, maybe letting the valve rock a little in the guide. The
>> > noise
>> >> is
>> >> > a lower pitched noise than typical rocker noise. Don't know if that
>> > tells
>> >> > you anything though.
>> >> >
>> >> > Cory
>> >> >
>> >> > "tom" <tjctransport@optonline.net> wrote in message
>> >> > news:tRGZd.4201$iZ7.523@fe10.lga...
>> >> > > adjust your valves to zero lash, plus 1/4 turn. this should
> eliminate
>> >> your
>> >> > > problem
>> >> > > "Cory Dunkle" <cdnews@comcast.net> wrote in message
>> >> > > news:i6GdnYahrvGieavfRVn-og@comcast.com...
>> >> > > > I have a 302 ('86 block, 28oz imbalance) with '65 289 heads
> (round
>> >> > pushrod
>> >> > > > holes, rail rockers, 53.5cc chambers) it has a stockish hydraulic
>> > flat
>> >> > > > tappet cam.
>> >> > > >
>> >> > > > My #8 intake valve makes a ticking/tapping noise. It sounds a lot
>> > like
>> >> > > when
>> >> > > > a rocker arm is too loose, except perhaps a bit of a deeper tone.
>> > With
>> >> > the
>> >> > > > engine running and the valve cover off the noise is present. When
> I
>> >> push
>> >> > > the
>> >> > > > rocker arm (at the valve tip) toward the front of the motor, the
>> > noise
>> >> > > goes
>> >> > > > away and the motor doesn't make any noise. When I let go it will
>> > stay
>> >> > > silent
>> >> > > > for a few seconds, then start making the nosie again. If I push
> the
>> >> > rocker
>> >> > > > arm (at the valve tip) toward the back of the motor, it will also
>> > make
>> >> > the
>> >> > > > noise. The motor does not make this noise when cold (if it does,
> it
>> > is
>> >> > > very
>> >> > > > faint), only after running for 5-10 minutes to get up to
>> > temperature.
>> >> > > >
>> >> > > > This noise is not present when turning the motor over by hand. I
>> >> checked
>> >> > > for
>> >> > > > clearance issues between the rails on the rocker arm and the
>> > retainer,
>> >> > > there
>> >> > > > are none. I checekd to ensure the rocker arm slot is long enough
> and
>> >> is
>> >> > > not
>> >> > > > binding on the stud, it is not. There is no sign of abnormal wear
> on
>> >> the
>> >> > > > valve tip or the rocker arm. The valve spring and damper appear
> to
>> > be
>> >> > > intact
>> >> > > > and not binding. The damper does not appear to be hanging or
> binding
>> >> on
>> >> > > the
>> >> > > > spring.
>> >> > > >
>> >> > > > If anyone has any thoughts on what this may be I'd appreciate it.
>> >> > > >
>> >> > > > Cory
>> >> > > >
>> >> > > >
>> >> > >
>> >> > >
>> >> >
>> >> >
>> >>
>> >>
>> >
>> >
>>
>>
>
>

Cory Dunkle

"pick one" <try again!> wrote in message
news:s9SdnedyuJWEH6XfRVn-gA@comcast.com...
>
> "Cory Dunkle" <cdnews@comcast.net> wrote in message
> news:C5Odnfu9xOE606XfRVn-rA@comcast.com...
> >I remember now why I stopped reading and posting to this group. Too many
> > smart-asses like you being rude. I think it's clear I've done a little
more
> > than just sit there tightening down on the rocker (can't tighten a
lifter,
> > except perhaps with a different spring, smart-ass).
> >
>
> You can over tighten a lifter till the internal spring is collapsed, now
it's a
> solid lifter. Once a lifter is adjusted it should never need adjusting.

Never say never... After 200,000 miles there may be enough wear to need a
little adjusting (a common problem with late model 302s with high mileage,
slight tick in the valvetrain as the rocker arms are the positive stop type
and therefore not adjsutable). There is also the fact that the lock nuts
used on these heads _will_ loosen over time. It's a fact and unavoidable.
Using polylocks will prevent rockers backing off, or using two lock nuts
(instead of one) will help. I've never heard of an engine that does not need
the rockers adjusted periodically. 200,000 miles and I imagine any engine
will make a little rocker noise unless adjusted. You do mention lfiters
needing adjustment though (which lifters can not be adjusted, to my
knowledge), so maybe you are referring to something else. I am assuming you
are referring to adjusting the rocker arms.

> > In any case, while measuring the travel may be worthwhile, I don't
> > understand how that may cause a ticking/tapping that would stop when
> > applying pressure on the side of the valve. If the cam lobe were worn
that
> > should only result in less valve lift. Adjusting the rocker properly
should
> > ensure there is no noise as there is no slack anywhere from camshaft to
> > valve. So, if you don't mind, I'm curious as to how a slightly worn cam
lobe
> > would make the rather loud noise my engien is making.
> >
> In side your type of lifter is a plunger held up by a spring. There are
two oil
> passage ways. there is also a check valve. The job of the lifter is to
provide
> oil supply to the rocker through the lifter, that is done with the
plunger. This
> is what happens. When the lifter is on the base of the cam lobe ( valve
closed )
> the oil passage on the side ( notice the hole is also in a grove ) of the
lifter
> is feed with oil from the oil pump ( the lifter is also a valve of
sorts ). This
> fills the space beneath the plunger. As the cam rotates and pushes the
lifter up
> it's bore the hole in the side of the lifter moves up ( duh ). Now the
lifter
> acts as a valve, the hole and grove is past the feed hole in the block, so
the
> oil passage is closed. The space beneath the plunger is now full. As the
lifter
> continues up it tries to push against the push rod which at this point the
oil
> pressure in the lifter combined with the spring over comes the pressure of
the
> valve spring. As the lifter gets towards the top of its travel the valve
spring
> is near it's fully compressed state, because of this spring pressure of
the
> valve over comes the oil pressure and spring pressure in the space below
the
> plunger moving the plunger down into the lifter. The oil pressure in side
the
> lifter raises up enough to open the check valve and that small amount of
oil is
> now forced into the push rod. As the cam rotates to the down slope of the
lobe
> the spring pressure from the valve pushes the lifter down into its bore.
As the
> valve closes the spring pressure becomes less than the spring pressure in
side
> the lifter, so now the plunger moves up in it's bore. Then the cycle
starts over
> again. Eventually the push rod gets full so any extra oil gets pushed out
lubing
> the rest of the valve train. That is why lifters always tick for a while
when
> new ones are installed and why there is always a delay for oil squirting
out the
> top of the push rod. That being said you can see why just tightening the
valve
> does nothing but cause more problems. You run the risk of collapsing the
lifter,
> that will starve the rest of the valve train of oil.

I have taken the lifter apart, cleaned and inspected it. It appears to be in
good condition. Regardless, your explanation of how a hydraulic lifter works
does not explain how a worn cam lobe will cause excess noise.

> > For what it's worth the motor only has 18,000 miles on it and was
properly
> > broken in, and looking down the head all rockers appear to have the same
> > travel (I know that doesn't necessarily mean much, but I've seen engines
> > with wiped cam lobes and it was obvious to me that those particular
valves
> > were not opening as far as the others).
> >
>
> It only takes a few thousands to make lifter noise. Didnt you recently say
you
> over heated this engine by running it with no coolant? Thats all it takes
to
> destroy a lifter.

No, that was a 289 I had a good while ago (this engine is a 302). This
engine has been treated properly it's entire life. It is a year old and has
18,000 miles on it. The heads were used for a few thousand miles on a
different engine and have not been 'abused' or neglected.

At this point I'm thinking it's eitehr the valve spring/damper, or the valve
guide. I don't see what else it could be that is causing this noise.

Cory

> > Cory
> >
> > "pick one" <try again!> wrote in message
> > news:CNCdnSadv78ON6rfRVn-sA@comcast.com...
> >>
> >> Instead of constantly just tightening the lifter which does nothing but
> > limit
> >> its job why don't you measure the rocker travel. Do some real
diagnosis.
> > Install
> >> a dial indicator on a good rocker and measure the travel while slowly
> > turning
> >> over the engine. Then do the same on the suspect rocker. Make sure that
if
> > the