I had a similar situation on my 02 tj. 4L. I never noticed the bubbling in
the coolant, but I also never checked because mine occurred at 20k miles and
I brought it back to the dealer.

Like you, I did not see any leaks, no bubbles in the oil, no smoke; nothing
typical of a bad headgasket or cracked head. I think I was losing coolant at
a similar rate that you are.(that was 2 years ago, I cant quite recall the
exact loss rate.)

I don't want to ruin your day, but mine was a cracked head.

I hope yours turns out to be a gasket or something ridiculous.

John
<loren.betts@gmail.com> wrote in message
news:1151784870.798465.269050@v61g2000cwv.googlegr oups.com...
> Hi All,
>
> Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
> past few years replaced radiator, thermostat, water pump. Now I have a
> mysterious coolant loss. No visible leaks. Did compression test (not
> leak down). All cyclinders are 185 +- 10 psi.
>
> What I noticed is that if I take the rad cap off and start the
> engine...as it warms up the coolant starts to rise out of the top.
> When I rev up the motor the coolant goes down and does not over flow.
> However if I then release the throttle the coolant rises and over
> flows. I then watched more closely at it looks like there are bubbles
> that come up ver so often.
>
> This to me is pointing to a bad head gasket or head.
>
> What are your thoughts? Any other things to try before I pull the head
> off and spend the $250 for all the gaskets?
>
> Help!
>
> Loren
>

 

Ditto on my '01 XJ. Coolant loss was cracked head. The engine only had 29K
miles. So warranty covered it.

Brian

"John" <jstio@optonline.net> wrote in message
news:zhOpg.28$ZM6.13@fe08.lga...
>I had a similar situation on my 02 tj. 4L. I never noticed the bubbling in
>the coolant, but I also never checked because mine occurred at 20k miles
>and I brought it back to the dealer.
>
> Like you, I did not see any leaks, no bubbles in the oil, no smoke;
> nothing typical of a bad headgasket or cracked head. I think I was losing
> coolant at a similar rate that you are.(that was 2 years ago, I cant quite
> recall the exact loss rate.)
>
> I don't want to ruin your day, but mine was a cracked head.
>
> I hope yours turns out to be a gasket or something ridiculous.
>
> John
> <loren.betts@gmail.com> wrote in message
> news:1151784870.798465.269050@v61g2000cwv.googlegr oups.com...
>> Hi All,
>>
>> Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
>> past few years replaced radiator, thermostat, water pump. Now I have a
>> mysterious coolant loss. No visible leaks. Did compression test (not
>> leak down). All cyclinders are 185 +- 10 psi.
>>
>> What I noticed is that if I take the rad cap off and start the
>> engine...as it warms up the coolant starts to rise out of the top.
>> When I rev up the motor the coolant goes down and does not over flow.
>> However if I then release the throttle the coolant rises and over
>> flows. I then watched more closely at it looks like there are bubbles
>> that come up ver so often.
>>
>> This to me is pointing to a bad head gasket or head.
>>
>> What are your thoughts? Any other things to try before I pull the head
>> off and spend the $250 for all the gaskets?
>>
>> Help!
>>
>> Loren
>>
>
>

 

Ditto on my '01 XJ. Coolant loss was cracked head. The engine only had 29K
miles. So warranty covered it.

Brian

"John" <jstio@optonline.net> wrote in message
news:zhOpg.28$ZM6.13@fe08.lga...
>I had a similar situation on my 02 tj. 4L. I never noticed the bubbling in
>the coolant, but I also never checked because mine occurred at 20k miles
>and I brought it back to the dealer.
>
> Like you, I did not see any leaks, no bubbles in the oil, no smoke;
> nothing typical of a bad headgasket or cracked head. I think I was losing
> coolant at a similar rate that you are.(that was 2 years ago, I cant quite
> recall the exact loss rate.)
>
> I don't want to ruin your day, but mine was a cracked head.
>
> I hope yours turns out to be a gasket or something ridiculous.
>
> John
> <loren.betts@gmail.com> wrote in message
> news:1151784870.798465.269050@v61g2000cwv.googlegr oups.com...
>> Hi All,
>>
>> Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
>> past few years replaced radiator, thermostat, water pump. Now I have a
>> mysterious coolant loss. No visible leaks. Did compression test (not
>> leak down). All cyclinders are 185 +- 10 psi.
>>
>> What I noticed is that if I take the rad cap off and start the
>> engine...as it warms up the coolant starts to rise out of the top.
>> When I rev up the motor the coolant goes down and does not over flow.
>> However if I then release the throttle the coolant rises and over
>> flows. I then watched more closely at it looks like there are bubbles
>> that come up ver so often.
>>
>> This to me is pointing to a bad head gasket or head.
>>
>> What are your thoughts? Any other things to try before I pull the head
>> off and spend the $250 for all the gaskets?
>>
>> Help!
>>
>> Loren
>>
>
>

 

Ditto on my '01 XJ. Coolant loss was cracked head. The engine only had 29K
miles. So warranty covered it.

Brian

"John" <jstio@optonline.net> wrote in message
news:zhOpg.28$ZM6.13@fe08.lga...
>I had a similar situation on my 02 tj. 4L. I never noticed the bubbling in
>the coolant, but I also never checked because mine occurred at 20k miles
>and I brought it back to the dealer.
>
> Like you, I did not see any leaks, no bubbles in the oil, no smoke;
> nothing typical of a bad headgasket or cracked head. I think I was losing
> coolant at a similar rate that you are.(that was 2 years ago, I cant quite
> recall the exact loss rate.)
>
> I don't want to ruin your day, but mine was a cracked head.
>
> I hope yours turns out to be a gasket or something ridiculous.
>
> John
> <loren.betts@gmail.com> wrote in message
> news:1151784870.798465.269050@v61g2000cwv.googlegr oups.com...
>> Hi All,
>>
>> Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
>> past few years replaced radiator, thermostat, water pump. Now I have a
>> mysterious coolant loss. No visible leaks. Did compression test (not
>> leak down). All cyclinders are 185 +- 10 psi.
>>
>> What I noticed is that if I take the rad cap off and start the
>> engine...as it warms up the coolant starts to rise out of the top.
>> When I rev up the motor the coolant goes down and does not over flow.
>> However if I then release the throttle the coolant rises and over
>> flows. I then watched more closely at it looks like there are bubbles
>> that come up ver so often.
>>
>> This to me is pointing to a bad head gasket or head.
>>
>> What are your thoughts? Any other things to try before I pull the head
>> off and spend the $250 for all the gaskets?
>>
>> Help!
>>
>> Loren
>>
>
>

 

you can guess all you want but a cooling system pressure test is what u need to
put on the vehicle and look for leaks this way u can verify any external leaks

there is a kit available now that u can add the engine coolant to and mix if the
head gasket is leaking and combustion chamber chemicals into the coolant it will
show up and to what degree. most well stocked parts stores can get it
how long ago was the water pump replaced?? could be the wrong one if it was
recent there is 2 versions that spin in opposite directions


Mike Romain wrote:

> I mean a leak into a cylinder will make the plug look clean like new.
>
> You can have leaks into the exhaust. Usually you can actually see smoke
> coming out the rad or smell it when that happens. You also might be
> able to feel puffs of compression if you put your hand over the rad
> opening when it is first going.
>
> I had a head gasket go like that an the coolant foamed up like a wash
> machine with dish soap in it. Here is a photo:
> http://www.imagestation.com/album/pi...?id=4290636987
>
> Mike
>
> bbb wrote:
> >
> > Thanks Mike,
> >
> > I pulled all the plugs and they all looked clean. I replaced them
> > around a month ago. One of the plugs had more carbon on the outer rim
> > then the others but not a noticeable difference on the electrodes.
> >
> > Mike Romain wrote:
> > > If you pull the plugs and look at them, a plug that has seen coolant
> > > will be super clean.
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > > Canadian Off Road Trips Photos: Non members can still view!
> > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > (More Off Road album links at bottom of the view page)
> > >
> > > loren.betts@gmail.com wrote:
> > > >
> > > > Hi All,
> > > >
> > > > Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
> > > > past few years replaced radiator, thermostat, water pump. Now I have a
> > > > mysterious coolant loss. No visible leaks. Did compression test (not
> > > > leak down). All cyclinders are 185 +- 10 psi.
> > > >
> > > > What I noticed is that if I take the rad cap off and start the
> > > > engine...as it warms up the coolant starts to rise out of the top.
> > > > When I rev up the motor the coolant goes down and does not over flow.
> > > > However if I then release the throttle the coolant rises and over
> > > > flows. I then watched more closely at it looks like there are bubbles
> > > > that come up ver so often.
> > > >
> > > > This to me is pointing to a bad head gasket or head.
> > > >
> > > > What are your thoughts? Any other things to try before I pull the head
> > > > off and spend the $250 for all the gaskets?
> > > >
> > > > Help!
> > > >
> > > > Loren

 

you can guess all you want but a cooling system pressure test is what u need to
put on the vehicle and look for leaks this way u can verify any external leaks

there is a kit available now that u can add the engine coolant to and mix if the
head gasket is leaking and combustion chamber chemicals into the coolant it will
show up and to what degree. most well stocked parts stores can get it
how long ago was the water pump replaced?? could be the wrong one if it was
recent there is 2 versions that spin in opposite directions


Mike Romain wrote:

> I mean a leak into a cylinder will make the plug look clean like new.
>
> You can have leaks into the exhaust. Usually you can actually see smoke
> coming out the rad or smell it when that happens. You also might be
> able to feel puffs of compression if you put your hand over the rad
> opening when it is first going.
>
> I had a head gasket go like that an the coolant foamed up like a wash
> machine with dish soap in it. Here is a photo:
> http://www.imagestation.com/album/pi...?id=4290636987
>
> Mike
>
> bbb wrote:
> >
> > Thanks Mike,
> >
> > I pulled all the plugs and they all looked clean. I replaced them
> > around a month ago. One of the plugs had more carbon on the outer rim
> > then the others but not a noticeable difference on the electrodes.
> >
> > Mike Romain wrote:
> > > If you pull the plugs and look at them, a plug that has seen coolant
> > > will be super clean.
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > > Canadian Off Road Trips Photos: Non members can still view!
> > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > (More Off Road album links at bottom of the view page)
> > >
> > > loren.betts@gmail.com wrote:
> > > >
> > > > Hi All,
> > > >
> > > > Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
> > > > past few years replaced radiator, thermostat, water pump. Now I have a
> > > > mysterious coolant loss. No visible leaks. Did compression test (not
> > > > leak down). All cyclinders are 185 +- 10 psi.
> > > >
> > > > What I noticed is that if I take the rad cap off and start the
> > > > engine...as it warms up the coolant starts to rise out of the top.
> > > > When I rev up the motor the coolant goes down and does not over flow.
> > > > However if I then release the throttle the coolant rises and over
> > > > flows. I then watched more closely at it looks like there are bubbles
> > > > that come up ver so often.
> > > >
> > > > This to me is pointing to a bad head gasket or head.
> > > >
> > > > What are your thoughts? Any other things to try before I pull the head
> > > > off and spend the $250 for all the gaskets?
> > > >
> > > > Help!
> > > >
> > > > Loren

 

you can guess all you want but a cooling system pressure test is what u need to
put on the vehicle and look for leaks this way u can verify any external leaks

there is a kit available now that u can add the engine coolant to and mix if the
head gasket is leaking and combustion chamber chemicals into the coolant it will
show up and to what degree. most well stocked parts stores can get it
how long ago was the water pump replaced?? could be the wrong one if it was
recent there is 2 versions that spin in opposite directions


Mike Romain wrote:

> I mean a leak into a cylinder will make the plug look clean like new.
>
> You can have leaks into the exhaust. Usually you can actually see smoke
> coming out the rad or smell it when that happens. You also might be
> able to feel puffs of compression if you put your hand over the rad
> opening when it is first going.
>
> I had a head gasket go like that an the coolant foamed up like a wash
> machine with dish soap in it. Here is a photo:
> http://www.imagestation.com/album/pi...?id=4290636987
>
> Mike
>
> bbb wrote:
> >
> > Thanks Mike,
> >
> > I pulled all the plugs and they all looked clean. I replaced them
> > around a month ago. One of the plugs had more carbon on the outer rim
> > then the others but not a noticeable difference on the electrodes.
> >
> > Mike Romain wrote:
> > > If you pull the plugs and look at them, a plug that has seen coolant
> > > will be super clean.
> > >
> > > Mike
> > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > 88 Cherokee 235 BFG AT's
> > > Canadian Off Road Trips Photos: Non members can still view!
> > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > (More Off Road album links at bottom of the view page)
> > >
> > > loren.betts@gmail.com wrote:
> > > >
> > > > Hi All,
> > > >
> > > > Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
> > > > past few years replaced radiator, thermostat, water pump. Now I have a
> > > > mysterious coolant loss. No visible leaks. Did compression test (not
> > > > leak down). All cyclinders are 185 +- 10 psi.
> > > >
> > > > What I noticed is that if I take the rad cap off and start the
> > > > engine...as it warms up the coolant starts to rise out of the top.
> > > > When I rev up the motor the coolant goes down and does not over flow.
> > > > However if I then release the throttle the coolant rises and over
> > > > flows. I then watched more closely at it looks like there are bubbles
> > > > that come up ver so often.
> > > >
> > > > This to me is pointing to a bad head gasket or head.
> > > >
> > > > What are your thoughts? Any other things to try before I pull the head
> > > > off and spend the $250 for all the gaskets?
> > > >
> > > > Help!
> > > >
> > > > Loren

 

Thanks for all the feedback and suggestions. I will purchase the
coolant check as a first step. Anyone now where to get this? I guess
I'll try kragen or pep boys.

philthy wrote:
> you can guess all you want but a cooling system pressure test is what u need to
> put on the vehicle and look for leaks this way u can verify any external leaks
>
> there is a kit available now that u can add the engine coolant to and mix if the
> head gasket is leaking and combustion chamber chemicals into the coolant it will
> show up and to what degree. most well stocked parts stores can get it
> how long ago was the water pump replaced?? could be the wrong one if it was
> recent there is 2 versions that spin in opposite directions
>
>
> Mike Romain wrote:
>
> > I mean a leak into a cylinder will make the plug look clean like new.
> >
> > You can have leaks into the exhaust. Usually you can actually see smoke
> > coming out the rad or smell it when that happens. You also might be
> > able to feel puffs of compression if you put your hand over the rad
> > opening when it is first going.
> >
> > I had a head gasket go like that an the coolant foamed up like a wash
> > machine with dish soap in it. Here is a photo:
> > http://www.imagestation.com/album/pi...?id=4290636987
> >
> > Mike
> >
> > bbb wrote:
> > >
> > > Thanks Mike,
> > >
> > > I pulled all the plugs and they all looked clean. I replaced them
> > > around a month ago. One of the plugs had more carbon on the outer rim
> > > then the others but not a noticeable difference on the electrodes.
> > >
> > > Mike Romain wrote:
> > > > If you pull the plugs and look at them, a plug that has seen coolant
> > > > will be super clean.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > > Canadian Off Road Trips Photos: Non members can still view!
> > > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > > (More Off Road album links at bottom of the view page)
> > > >
> > > > loren.betts@gmail.com wrote:
> > > > >
> > > > > Hi All,
> > > > >
> > > > > Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
> > > > > past few years replaced radiator, thermostat, water pump. Now I have a
> > > > > mysterious coolant loss. No visible leaks. Did compression test (not
> > > > > leak down). All cyclinders are 185 +- 10 psi.
> > > > >
> > > > > What I noticed is that if I take the rad cap off and start the
> > > > > engine...as it warms up the coolant starts to rise out of the top.
> > > > > When I rev up the motor the coolant goes down and does not over flow.
> > > > > However if I then release the throttle the coolant rises and over
> > > > > flows. I then watched more closely at it looks like there are bubbles
> > > > > that come up ver so often.
> > > > >
> > > > > This to me is pointing to a bad head gasket or head.
> > > > >
> > > > > What are your thoughts? Any other things to try before I pull the head
> > > > > off and spend the $250 for all the gaskets?
> > > > >
> > > > > Help!
> > > > >
> > > > > Loren

 

Thanks for all the feedback and suggestions. I will purchase the
coolant check as a first step. Anyone now where to get this? I guess
I'll try kragen or pep boys.

philthy wrote:
> you can guess all you want but a cooling system pressure test is what u need to
> put on the vehicle and look for leaks this way u can verify any external leaks
>
> there is a kit available now that u can add the engine coolant to and mix if the
> head gasket is leaking and combustion chamber chemicals into the coolant it will
> show up and to what degree. most well stocked parts stores can get it
> how long ago was the water pump replaced?? could be the wrong one if it was
> recent there is 2 versions that spin in opposite directions
>
>
> Mike Romain wrote:
>
> > I mean a leak into a cylinder will make the plug look clean like new.
> >
> > You can have leaks into the exhaust. Usually you can actually see smoke
> > coming out the rad or smell it when that happens. You also might be
> > able to feel puffs of compression if you put your hand over the rad
> > opening when it is first going.
> >
> > I had a head gasket go like that an the coolant foamed up like a wash
> > machine with dish soap in it. Here is a photo:
> > http://www.imagestation.com/album/pi...?id=4290636987
> >
> > Mike
> >
> > bbb wrote:
> > >
> > > Thanks Mike,
> > >
> > > I pulled all the plugs and they all looked clean. I replaced them
> > > around a month ago. One of the plugs had more carbon on the outer rim
> > > then the others but not a noticeable difference on the electrodes.
> > >
> > > Mike Romain wrote:
> > > > If you pull the plugs and look at them, a plug that has seen coolant
> > > > will be super clean.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > > Canadian Off Road Trips Photos: Non members can still view!
> > > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > > (More Off Road album links at bottom of the view page)
> > > >
> > > > loren.betts@gmail.com wrote:
> > > > >
> > > > > Hi All,
> > > > >
> > > > > Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
> > > > > past few years replaced radiator, thermostat, water pump. Now I have a
> > > > > mysterious coolant loss. No visible leaks. Did compression test (not
> > > > > leak down). All cyclinders are 185 +- 10 psi.
> > > > >
> > > > > What I noticed is that if I take the rad cap off and start the
> > > > > engine...as it warms up the coolant starts to rise out of the top.
> > > > > When I rev up the motor the coolant goes down and does not over flow.
> > > > > However if I then release the throttle the coolant rises and over
> > > > > flows. I then watched more closely at it looks like there are bubbles
> > > > > that come up ver so often.
> > > > >
> > > > > This to me is pointing to a bad head gasket or head.
> > > > >
> > > > > What are your thoughts? Any other things to try before I pull the head
> > > > > off and spend the $250 for all the gaskets?
> > > > >
> > > > > Help!
> > > > >
> > > > > Loren

 

Thanks for all the feedback and suggestions. I will purchase the
coolant check as a first step. Anyone now where to get this? I guess
I'll try kragen or pep boys.

philthy wrote:
> you can guess all you want but a cooling system pressure test is what u need to
> put on the vehicle and look for leaks this way u can verify any external leaks
>
> there is a kit available now that u can add the engine coolant to and mix if the
> head gasket is leaking and combustion chamber chemicals into the coolant it will
> show up and to what degree. most well stocked parts stores can get it
> how long ago was the water pump replaced?? could be the wrong one if it was
> recent there is 2 versions that spin in opposite directions
>
>
> Mike Romain wrote:
>
> > I mean a leak into a cylinder will make the plug look clean like new.
> >
> > You can have leaks into the exhaust. Usually you can actually see smoke
> > coming out the rad or smell it when that happens. You also might be
> > able to feel puffs of compression if you put your hand over the rad
> > opening when it is first going.
> >
> > I had a head gasket go like that an the coolant foamed up like a wash
> > machine with dish soap in it. Here is a photo:
> > http://www.imagestation.com/album/pi...?id=4290636987
> >
> > Mike
> >
> > bbb wrote:
> > >
> > > Thanks Mike,
> > >
> > > I pulled all the plugs and they all looked clean. I replaced them
> > > around a month ago. One of the plugs had more carbon on the outer rim
> > > then the others but not a noticeable difference on the electrodes.
> > >
> > > Mike Romain wrote:
> > > > If you pull the plugs and look at them, a plug that has seen coolant
> > > > will be super clean.
> > > >
> > > > Mike
> > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > > > 88 Cherokee 235 BFG AT's
> > > > Canadian Off Road Trips Photos: Non members can still view!
> > > > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > > > (More Off Road album links at bottom of the view page)
> > > >
> > > > loren.betts@gmail.com wrote:
> > > > >
> > > > > Hi All,
> > > > >
> > > > > Here's a good one. Bought used Jeep 2000 wrangler with 4L. Over the
> > > > > past few years replaced radiator, thermostat, water pump. Now I have a
> > > > > mysterious coolant loss. No visible leaks. Did compression test (not
> > > > > leak down). All cyclinders are 185 +- 10 psi.
> > > > >
> > > > > What I noticed is that if I take the rad cap off and start the
> > > > > engine...as it warms up the coolant starts to rise out of the top.
> > > > > When I rev up the motor the coolant goes down and does not over flow.
> > > > > However if I then release the throttle the coolant rises and over
> > > > > flows. I then watched more closely at it looks like there are bubbles
> > > > > that come up ver so often.
> > > > >
> > > > > This to me is pointing to a bad head gasket or head.
> > > > >
> > > > > What are your thoughts? Any other things to try before I pull the head
> > > > > off and spend the $250 for all the gaskets?
> > > > >
> > > > > Help!
> > > > >
> > > > > Loren