Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Thanks for all the input so far.

Checking around with an improvised stethoscope, the noise seems to
come
from the engine close to cylinder ( 6 ?) , close to the place, where
the
PCV is located.

Take today's history for example. Started the cold (it's the tropics)
engine. No noise at all. Went to the local mall about 3 miles away,
and
no noise during the drive there. While slowly cruising at about 1,500
rpm through the parking area, the noise (more like a knocking, not a
ticking) appeared.
During idle, the knocking was still there, then stopped. With the car
parked, raving the engine up to about 1,500 to 2000 rpm and letting it
slow down to idle again, the symptoms came back during idle for about
30 Seconds to a minute, then stopped.

I decided to drive strait to the dealer who is only away another few
miles. On
the way there, no noise at all. At the dealer, only a very slight
ticking sound, but no knocking.

Every time I am at the dealer, there is only a ticking, but never a
strong knocking.
When this metallic knocking sound appears, you can hear it very
clearly, even quit far away from the car.

From reading through similar messages, I would say, it sounds perhaps
like the
"Piston Slap", but since I have a '99 model, this particular problem
should not
apply to my engine I guess.

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Exhaust pipe hitting on something is my next guess.

Or the heat shield on the cat is loose.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Robert Goldpalm wrote:
>
> Thanks for all the input so far.
>
> Checking around with an improvised stethoscope, the noise seems to
> come
> from the engine close to cylinder ( 6 ?) , close to the place, where
> the
> PCV is located.
>
> Take today's history for example. Started the cold (it's the tropics)
> engine. No noise at all. Went to the local mall about 3 miles away,
> and
> no noise during the drive there. While slowly cruising at about 1,500
> rpm through the parking area, the noise (more like a knocking, not a
> ticking) appeared.
> During idle, the knocking was still there, then stopped. With the car
> parked, raving the engine up to about 1,500 to 2000 rpm and letting it
> slow down to idle again, the symptoms came back during idle for about
> 30 Seconds to a minute, then stopped.
>
> I decided to drive strait to the dealer who is only away another few
> miles. On
> the way there, no noise at all. At the dealer, only a very slight
> ticking sound, but no knocking.
>
> Every time I am at the dealer, there is only a ticking, but never a
> strong knocking.
> When this metallic knocking sound appears, you can hear it very
> clearly, even quit far away from the car.
>
> From reading through similar messages, I would say, it sounds perhaps
> like the
> "Piston Slap", but since I have a '99 model, this particular problem
> should not
> apply to my engine I guess.

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Exhaust pipe hitting on something is my next guess.

Or the heat shield on the cat is loose.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Robert Goldpalm wrote:
>
> Thanks for all the input so far.
>
> Checking around with an improvised stethoscope, the noise seems to
> come
> from the engine close to cylinder ( 6 ?) , close to the place, where
> the
> PCV is located.
>
> Take today's history for example. Started the cold (it's the tropics)
> engine. No noise at all. Went to the local mall about 3 miles away,
> and
> no noise during the drive there. While slowly cruising at about 1,500
> rpm through the parking area, the noise (more like a knocking, not a
> ticking) appeared.
> During idle, the knocking was still there, then stopped. With the car
> parked, raving the engine up to about 1,500 to 2000 rpm and letting it
> slow down to idle again, the symptoms came back during idle for about
> 30 Seconds to a minute, then stopped.
>
> I decided to drive strait to the dealer who is only away another few
> miles. On
> the way there, no noise at all. At the dealer, only a very slight
> ticking sound, but no knocking.
>
> Every time I am at the dealer, there is only a ticking, but never a
> strong knocking.
> When this metallic knocking sound appears, you can hear it very
> clearly, even quit far away from the car.
>
> From reading through similar messages, I would say, it sounds perhaps
> like the
> "Piston Slap", but since I have a '99 model, this particular problem
> should not
> apply to my engine I guess.

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Exhaust pipe hitting on something is my next guess.

Or the heat shield on the cat is loose.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Robert Goldpalm wrote:
>
> Thanks for all the input so far.
>
> Checking around with an improvised stethoscope, the noise seems to
> come
> from the engine close to cylinder ( 6 ?) , close to the place, where
> the
> PCV is located.
>
> Take today's history for example. Started the cold (it's the tropics)
> engine. No noise at all. Went to the local mall about 3 miles away,
> and
> no noise during the drive there. While slowly cruising at about 1,500
> rpm through the parking area, the noise (more like a knocking, not a
> ticking) appeared.
> During idle, the knocking was still there, then stopped. With the car
> parked, raving the engine up to about 1,500 to 2000 rpm and letting it
> slow down to idle again, the symptoms came back during idle for about
> 30 Seconds to a minute, then stopped.
>
> I decided to drive strait to the dealer who is only away another few
> miles. On
> the way there, no noise at all. At the dealer, only a very slight
> ticking sound, but no knocking.
>
> Every time I am at the dealer, there is only a ticking, but never a
> strong knocking.
> When this metallic knocking sound appears, you can hear it very
> clearly, even quit far away from the car.
>
> From reading through similar messages, I would say, it sounds perhaps
> like the
> "Piston Slap", but since I have a '99 model, this particular problem
> should not
> apply to my engine I guess.

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Now it's beginning to sound like a bad lifter letting the pushrod get
slack in it - notice any roughnes in the engine when it's banging
away? Given a little bleed down, the extra spacing will produce a
pretty good noise when the pushrod has any substantial air gap between
it and the rocker arm. Another oil change might clean this up or
trying one change with a heavier weight oil - like going from 10-30 to
20-40 - might make a difference.

On Tue, 11 Nov 2003 05:39:52 UTC goldpalm@loxinfo.co.th (Robert
Goldpalm) wrote:

> Thanks for all the input so far.
>
> Checking around with an improvised stethoscope, the noise seems to
> come
> from the engine close to cylinder ( 6 ?) , close to the place, where
> the
> PCV is located.
>
> Take today's history for example. Started the cold (it's the tropics)
> engine. No noise at all. Went to the local mall about 3 miles away,
> and
> no noise during the drive there. While slowly cruising at about 1,500
> rpm through the parking area, the noise (more like a knocking, not a
> ticking) appeared.
> During idle, the knocking was still there, then stopped. With the car
> parked, raving the engine up to about 1,500 to 2000 rpm and letting it
> slow down to idle again, the symptoms came back during idle for about
> 30 Seconds to a minute, then stopped.
>
> I decided to drive strait to the dealer who is only away another few
> miles. On
> the way there, no noise at all. At the dealer, only a very slight
> ticking sound, but no knocking.
>
> Every time I am at the dealer, there is only a ticking, but never a
> strong knocking.
> When this metallic knocking sound appears, you can hear it very
> clearly, even quit far away from the car.
>
> From reading through similar messages, I would say, it sounds perhaps
> like the
> "Piston Slap", but since I have a '99 model, this particular problem
> should not
> apply to my engine I guess.


--
Will Honea <whonea@codenet.net>

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Now it's beginning to sound like a bad lifter letting the pushrod get
slack in it - notice any roughnes in the engine when it's banging
away? Given a little bleed down, the extra spacing will produce a
pretty good noise when the pushrod has any substantial air gap between
it and the rocker arm. Another oil change might clean this up or
trying one change with a heavier weight oil - like going from 10-30 to
20-40 - might make a difference.

On Tue, 11 Nov 2003 05:39:52 UTC goldpalm@loxinfo.co.th (Robert
Goldpalm) wrote:

> Thanks for all the input so far.
>
> Checking around with an improvised stethoscope, the noise seems to
> come
> from the engine close to cylinder ( 6 ?) , close to the place, where
> the
> PCV is located.
>
> Take today's history for example. Started the cold (it's the tropics)
> engine. No noise at all. Went to the local mall about 3 miles away,
> and
> no noise during the drive there. While slowly cruising at about 1,500
> rpm through the parking area, the noise (more like a knocking, not a
> ticking) appeared.
> During idle, the knocking was still there, then stopped. With the car
> parked, raving the engine up to about 1,500 to 2000 rpm and letting it
> slow down to idle again, the symptoms came back during idle for about
> 30 Seconds to a minute, then stopped.
>
> I decided to drive strait to the dealer who is only away another few
> miles. On
> the way there, no noise at all. At the dealer, only a very slight
> ticking sound, but no knocking.
>
> Every time I am at the dealer, there is only a ticking, but never a
> strong knocking.
> When this metallic knocking sound appears, you can hear it very
> clearly, even quit far away from the car.
>
> From reading through similar messages, I would say, it sounds perhaps
> like the
> "Piston Slap", but since I have a '99 model, this particular problem
> should not
> apply to my engine I guess.


--
Will Honea <whonea@codenet.net>

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Now it's beginning to sound like a bad lifter letting the pushrod get
slack in it - notice any roughnes in the engine when it's banging
away? Given a little bleed down, the extra spacing will produce a
pretty good noise when the pushrod has any substantial air gap between
it and the rocker arm. Another oil change might clean this up or
trying one change with a heavier weight oil - like going from 10-30 to
20-40 - might make a difference.

On Tue, 11 Nov 2003 05:39:52 UTC goldpalm@loxinfo.co.th (Robert
Goldpalm) wrote:

> Thanks for all the input so far.
>
> Checking around with an improvised stethoscope, the noise seems to
> come
> from the engine close to cylinder ( 6 ?) , close to the place, where
> the
> PCV is located.
>
> Take today's history for example. Started the cold (it's the tropics)
> engine. No noise at all. Went to the local mall about 3 miles away,
> and
> no noise during the drive there. While slowly cruising at about 1,500
> rpm through the parking area, the noise (more like a knocking, not a
> ticking) appeared.
> During idle, the knocking was still there, then stopped. With the car
> parked, raving the engine up to about 1,500 to 2000 rpm and letting it
> slow down to idle again, the symptoms came back during idle for about
> 30 Seconds to a minute, then stopped.
>
> I decided to drive strait to the dealer who is only away another few
> miles. On
> the way there, no noise at all. At the dealer, only a very slight
> ticking sound, but no knocking.
>
> Every time I am at the dealer, there is only a ticking, but never a
> strong knocking.
> When this metallic knocking sound appears, you can hear it very
> clearly, even quit far away from the car.
>
> From reading through similar messages, I would say, it sounds perhaps
> like the
> "Piston Slap", but since I have a '99 model, this particular problem
> should not
> apply to my engine I guess.


--
Will Honea <whonea@codenet.net>

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Thanks again for all the suggestions.

So far, I have now:

-Drained about one quarter of oil, refilled
with ATF and driven the car about 100 miles.

-Made a complete oil & filter (Mopar) change to Valvoline Maxlife
10W-40, a heavier weight oil as suggested here.

-This is the second day now with a 10W-40 oil fill, and this
morning, the engine has made again this distinct noise at
cold (82 F) start. The noise did not go away for a few minutes,
then resided from a loud metallic tick to a softer, more subdued
ticking sound that could be still heard most of the time during
driving.

-To accurately describe the sound is not so easy, but I would
say, it is similar to a smaller direct injected diesel engine,
comming from cylinder 6 or 5.

Does that sound like a lifter noise? If yes, what are the prospects?
Can the engine deteriorate more, or is it just an annoyance, one has to get used to?

The dealer where the car was purchased, switched from Chrysler
to Land Rover recently, and Jeeps are serviced now by the local Mercedes
dealer. There, they have only one mechanic who is responsible for
Jeeps, and he admitted, that he actually has never opened a 4.0 L/6
engine before.
Now, unlucky me, if the engine really needs replacement lifters,
that guy will somehow experiment with my engine for the first time.
I can also not sell the car because of the noise it makes. I could just
drive until something gives, and that would be it, but perhaps it would
be a long way from now.

So, what do you think?

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Thanks again for all the suggestions.

So far, I have now:

-Drained about one quarter of oil, refilled
with ATF and driven the car about 100 miles.

-Made a complete oil & filter (Mopar) change to Valvoline Maxlife
10W-40, a heavier weight oil as suggested here.

-This is the second day now with a 10W-40 oil fill, and this
morning, the engine has made again this distinct noise at
cold (82 F) start. The noise did not go away for a few minutes,
then resided from a loud metallic tick to a softer, more subdued
ticking sound that could be still heard most of the time during
driving.

-To accurately describe the sound is not so easy, but I would
say, it is similar to a smaller direct injected diesel engine,
comming from cylinder 6 or 5.

Does that sound like a lifter noise? If yes, what are the prospects?
Can the engine deteriorate more, or is it just an annoyance, one has to get used to?

The dealer where the car was purchased, switched from Chrysler
to Land Rover recently, and Jeeps are serviced now by the local Mercedes
dealer. There, they have only one mechanic who is responsible for
Jeeps, and he admitted, that he actually has never opened a 4.0 L/6
engine before.
Now, unlucky me, if the engine really needs replacement lifters,
that guy will somehow experiment with my engine for the first time.
I can also not sell the car because of the noise it makes. I could just
drive until something gives, and that would be it, but perhaps it would
be a long way from now.

So, what do you think?

Re: Hammering / knocking noise on 4.0L6 '99 Cherokee
 

Thanks again for all the suggestions.

So far, I have now:

-Drained about one quarter of oil, refilled
with ATF and driven the car about 100 miles.

-Made a complete oil & filter (Mopar) change to Valvoline Maxlife
10W-40, a heavier weight oil as suggested here.

-This is the second day now with a 10W-40 oil fill, and this
morning, the engine has made again this distinct noise at
cold (82 F) start. The noise did not go away for a few minutes,
then resided from a loud metallic tick to a softer, more subdued
ticking sound that could be still heard most of the time during
driving.

-To accurately describe the sound is not so easy, but I would
say, it is similar to a smaller direct injected diesel engine,
comming from cylinder 6 or 5.

Does that sound like a lifter noise? If yes, what are the prospects?
Can the engine deteriorate more, or is it just an annoyance, one has to get used to?

The dealer where the car was purchased, switched from Chrysler
to Land Rover recently, and Jeeps are serviced now by the local Mercedes
dealer. There, they have only one mechanic who is responsible for
Jeeps, and he admitted, that he actually has never opened a 4.0 L/6
engine before.
Now, unlucky me, if the engine really needs replacement lifters,
that guy will somehow experiment with my engine for the first time.
I can also not sell the car because of the noise it makes. I could just
drive until something gives, and that would be it, but perhaps it would
be a long way from now.

So, what do you think?