Oh boy, what's that noise?
08-06-2007, 02:30 PM
#14
Guest
Posts: n/a
Re: Oh boy, what's that noise?
I may have a similar issue. Does the rattle go away when you step on
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
08-06-2007, 02:30 PM
#15
Guest
Posts: n/a
Re: Oh boy, what's that noise?
I may have a similar issue. Does the rattle go away when you step on
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
08-06-2007, 02:30 PM
#16
Guest
Posts: n/a
Re: Oh boy, what's that noise?
I may have a similar issue. Does the rattle go away when you step on
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
08-06-2007, 02:30 PM
#17
Guest
Posts: n/a
Re: Oh boy, what's that noise?
I may have a similar issue. Does the rattle go away when you step on
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
the clutch? I think there was a TSB out on this. There was a problem
with some spring holding the clutch when the Jeep was idle.
I brought my Jeep to the dealership and asked they fix per the TSB.
Either the fix didn't work or they just charged me for nothing.
On Jul 23, 4:18 pm, Jon <jongodd...@gmail.com> wrote:
> '97 TJ, 4.0, roughly 130-140k on the odometer.
>
> Bear with me, as I'm trying to narrow down the source of a persistent
> engine noise. I'm well versed in mechanics, but this is the first
> engine "rattle" I've run across that has been more noticeable at idle/
> deceleration than under a load -- as a matter of fact, it's gone once
> you get the slightest load on the engine. I'd say it's louder than
> the constant tap-tap-tap of a bad lifter or rocker, but far softer
> than bearing noise. At idle, it the sound oscillates a bit and isn't
> quite as "even" as it is upon deceleration (where it sounds in time
> with every cylinder). Based upon the sound, my thoughts wander toward
> piston slap or a really loose timing chain, but that doesn't gel with
> the no-noise factor under a load, or with every other worn-out engine
> I've dealt with.
>
> I only ask now because, with the recent failure of an idle control
> valve, "honey" idled in traffic on the way home at 3,000
> rpm......which happens to be right around the no-load resonant
> frequency of this sound....and either it's a fair bit louder now or my
> head makes me think so.
>
> Just to cover a few bases:
>
> Not transmission/clutch related.
> Not an exhaust leak.
> 35 psi oil pressure at idle, hot on a manual gauge with 10w30.
> Runs and idles smooth.
> Present hot and cold.
> The harmonic dampener not hitting the timing cover.
> Sound does not emanate from inside the valve cover.
>
> Hoping you all can shed some light on this issue -- I know this engine
> can be dependable and has a few noises that creep up over time, I'd
> just hate to miss an opportunity to service an overlooked part during
> a maintenance tear-down....or worse yet dive into a sand bowl with a
> real soft engine...
>
> Thanks in advance,
>
> Jon
08-07-2007, 08:40 PM
#18
Guest
Posts: n/a
Re: Oh boy, what's that noise?
On Aug 6, 11:30 am, Nick ------ <nixon8...@gmail.com> wrote:
> I may have a similar issue. Does the rattle go away when you step on
> the clutch? I think there was a TSB out on this. There was a problem
> with some spring holding the clutch when the Jeep was idle.
>
> I brought my Jeep to the dealership and asked they fix per the TSB.
> Either the fix didn't work or they just charged me for nothing.
>
Hi Nick,
Sorry hear of your bad luck, at least that's one item "checked off".
The noise I'm referring to is definitely engine internals, not related
to clutch or transmission operation. Rapidly developing into a "run
it 'til it breaks" issue -- but thanks for the tip.
Jon
> I may have a similar issue. Does the rattle go away when you step on
> the clutch? I think there was a TSB out on this. There was a problem
> with some spring holding the clutch when the Jeep was idle.
>
> I brought my Jeep to the dealership and asked they fix per the TSB.
> Either the fix didn't work or they just charged me for nothing.
>
Hi Nick,
Sorry hear of your bad luck, at least that's one item "checked off".
The noise I'm referring to is definitely engine internals, not related
to clutch or transmission operation. Rapidly developing into a "run
it 'til it breaks" issue -- but thanks for the tip.
Jon
08-07-2007, 08:40 PM
#19
Guest
Posts: n/a
Re: Oh boy, what's that noise?
On Aug 6, 11:30 am, Nick ------ <nixon8...@gmail.com> wrote:
> I may have a similar issue. Does the rattle go away when you step on
> the clutch? I think there was a TSB out on this. There was a problem
> with some spring holding the clutch when the Jeep was idle.
>
> I brought my Jeep to the dealership and asked they fix per the TSB.
> Either the fix didn't work or they just charged me for nothing.
>
Hi Nick,
Sorry hear of your bad luck, at least that's one item "checked off".
The noise I'm referring to is definitely engine internals, not related
to clutch or transmission operation. Rapidly developing into a "run
it 'til it breaks" issue -- but thanks for the tip.
Jon
> I may have a similar issue. Does the rattle go away when you step on
> the clutch? I think there was a TSB out on this. There was a problem
> with some spring holding the clutch when the Jeep was idle.
>
> I brought my Jeep to the dealership and asked they fix per the TSB.
> Either the fix didn't work or they just charged me for nothing.
>
Hi Nick,
Sorry hear of your bad luck, at least that's one item "checked off".
The noise I'm referring to is definitely engine internals, not related
to clutch or transmission operation. Rapidly developing into a "run
it 'til it breaks" issue -- but thanks for the tip.
Jon
08-07-2007, 08:40 PM
#20
Guest
Posts: n/a
Re: Oh boy, what's that noise?
On Aug 6, 11:30 am, Nick ------ <nixon8...@gmail.com> wrote:
> I may have a similar issue. Does the rattle go away when you step on
> the clutch? I think there was a TSB out on this. There was a problem
> with some spring holding the clutch when the Jeep was idle.
>
> I brought my Jeep to the dealership and asked they fix per the TSB.
> Either the fix didn't work or they just charged me for nothing.
>
Hi Nick,
Sorry hear of your bad luck, at least that's one item "checked off".
The noise I'm referring to is definitely engine internals, not related
to clutch or transmission operation. Rapidly developing into a "run
it 'til it breaks" issue -- but thanks for the tip.
Jon
> I may have a similar issue. Does the rattle go away when you step on
> the clutch? I think there was a TSB out on this. There was a problem
> with some spring holding the clutch when the Jeep was idle.
>
> I brought my Jeep to the dealership and asked they fix per the TSB.
> Either the fix didn't work or they just charged me for nothing.
>
Hi Nick,
Sorry hear of your bad luck, at least that's one item "checked off".
The noise I'm referring to is definitely engine internals, not related
to clutch or transmission operation. Rapidly developing into a "run
it 'til it breaks" issue -- but thanks for the tip.
Jon