Troy

Yup, it was overheating, steam and fluid and boiling out the bottle cap,
with it still on. I notice I can't tighten it either or it will just click
over the stoppin point and be loose again.. damn plastic. I'm thinking of
replacing the bottle and cap to see if that fixes anything.

coolant wasn't changed before this happened... but I did notice i was a
quart low on oil. Maybe I needed that quart to keep cool? I added a quart
today and it still overheated.

Fan is wired correctly, although I wonder if and when I get the AC fixed if
it'll overheat when its on. The PO said he neighbor wired to fan to run at
all times since it was overheating to begin with.

Hmm, noticed that the valve cover was leaking a bit of oil, will check the
head gasket also. I'm assuming it even has the original radiator and I
heard someone say to replace it after 10 years, well it's been 16 if nobody
else has.

I'll check up on the things you mention and give ya'll a follow up.

Troy

Troy

Yup, it was overheating, steam and fluid and boiling out the bottle cap,
with it still on. I notice I can't tighten it either or it will just click
over the stoppin point and be loose again.. damn plastic. I'm thinking of
replacing the bottle and cap to see if that fixes anything.

coolant wasn't changed before this happened... but I did notice i was a
quart low on oil. Maybe I needed that quart to keep cool? I added a quart
today and it still overheated.

Fan is wired correctly, although I wonder if and when I get the AC fixed if
it'll overheat when its on. The PO said he neighbor wired to fan to run at
all times since it was overheating to begin with.

Hmm, noticed that the valve cover was leaking a bit of oil, will check the
head gasket also. I'm assuming it even has the original radiator and I
heard someone say to replace it after 10 years, well it's been 16 if nobody
else has.

I'll check up on the things you mention and give ya'll a follow up.

Troy

Troy

Yup, it was overheating, steam and fluid and boiling out the bottle cap,
with it still on. I notice I can't tighten it either or it will just click
over the stoppin point and be loose again.. damn plastic. I'm thinking of
replacing the bottle and cap to see if that fixes anything.

coolant wasn't changed before this happened... but I did notice i was a
quart low on oil. Maybe I needed that quart to keep cool? I added a quart
today and it still overheated.

Fan is wired correctly, although I wonder if and when I get the AC fixed if
it'll overheat when its on. The PO said he neighbor wired to fan to run at
all times since it was overheating to begin with.

Hmm, noticed that the valve cover was leaking a bit of oil, will check the
head gasket also. I'm assuming it even has the original radiator and I
heard someone say to replace it after 10 years, well it's been 16 if nobody
else has.

I'll check up on the things you mention and give ya'll a follow up.

Troy

Jeff DeWitt

Troy wrote:
> Yup, it was overheating, steam and fluid and boiling out the bottle cap,
> with it still on. I notice I can't tighten it either or it will just click
> over the stoppin point and be loose again.. damn plastic. I'm thinking of
> replacing the bottle and cap to see if that fixes anything.

I don't think those caps hold pressure, it's just the one on the
radiator that does.
>
> coolant wasn't changed before this happened... but I did notice i was a
> quart low on oil. Maybe I needed that quart to keep cool? I added a quart
> today and it still overheated.

While oil does help cool the engine being a quart low isn't going to
make it overheat.
>
> Fan is wired correctly, although I wonder if and when I get the AC fixed if
> it'll overheat when its on. The PO said he neighbor wired to fan to run at
> all times since it was overheating to begin with.

I figured as much... the Jeep started overheating so the PO tried a
Micky Mouse fix instead of figuring out what was wrong.
>
> Hmm, noticed that the valve cover was leaking a bit of oil, will check the
> head gasket also. I'm assuming it even has the original radiator and I
> heard someone say to replace it after 10 years, well it's been 16 if nobody
> else has.

They all leak oil, it's annoying but usually nothing more than that. My
Jeep ran great for 10 years and 300,000 miles with it's original
radiator, and never overheated except when the water pump went bad or
when I'd flushed out the cooling system and had a big bubble in it.
However when the engine was replaced they found the radiator was pretty
rotten, it not only had lots of rust and stuff in it but it had just
started leaking at one of the tanks.
>
> I'll check up on the things you mention and give ya'll a follow up.
>
> Troy
>
>

The radiators and water pumps aren't that expensive for these beasts.
If it was mine I'd first make sure it didn't have a bad head gasket. If
that was OK and I was planning on keeping it I'd put in a new water
pump, radiator, belts and hoses, and before removing the old parts I'd
give the engine a very through flushing out.

I'd also hook the fan back up properly.

Good luck, looking forward to hear what you find.

Jeff DeWitt

Jeff DeWitt

Troy wrote:
> Yup, it was overheating, steam and fluid and boiling out the bottle cap,
> with it still on. I notice I can't tighten it either or it will just click
> over the stoppin point and be loose again.. damn plastic. I'm thinking of
> replacing the bottle and cap to see if that fixes anything.

I don't think those caps hold pressure, it's just the one on the
radiator that does.
>
> coolant wasn't changed before this happened... but I did notice i was a
> quart low on oil. Maybe I needed that quart to keep cool? I added a quart
> today and it still overheated.

While oil does help cool the engine being a quart low isn't going to
make it overheat.
>
> Fan is wired correctly, although I wonder if and when I get the AC fixed if
> it'll overheat when its on. The PO said he neighbor wired to fan to run at
> all times since it was overheating to begin with.

I figured as much... the Jeep started overheating so the PO tried a
Micky Mouse fix instead of figuring out what was wrong.
>
> Hmm, noticed that the valve cover was leaking a bit of oil, will check the
> head gasket also. I'm assuming it even has the original radiator and I
> heard someone say to replace it after 10 years, well it's been 16 if nobody
> else has.

They all leak oil, it's annoying but usually nothing more than that. My
Jeep ran great for 10 years and 300,000 miles with it's original
radiator, and never overheated except when the water pump went bad or
when I'd flushed out the cooling system and had a big bubble in it.
However when the engine was replaced they found the radiator was pretty
rotten, it not only had lots of rust and stuff in it but it had just
started leaking at one of the tanks.
>
> I'll check up on the things you mention and give ya'll a follow up.
>
> Troy
>
>

The radiators and water pumps aren't that expensive for these beasts.
If it was mine I'd first make sure it didn't have a bad head gasket. If
that was OK and I was planning on keeping it I'd put in a new water
pump, radiator, belts and hoses, and before removing the old parts I'd
give the engine a very through flushing out.

I'd also hook the fan back up properly.

Good luck, looking forward to hear what you find.

Jeff DeWitt

Jeff DeWitt

Troy wrote:
> Yup, it was overheating, steam and fluid and boiling out the bottle cap,
> with it still on. I notice I can't tighten it either or it will just click
> over the stoppin point and be loose again.. damn plastic. I'm thinking of
> replacing the bottle and cap to see if that fixes anything.

I don't think those caps hold pressure, it's just the one on the
radiator that does.
>
> coolant wasn't changed before this happened... but I did notice i was a
> quart low on oil. Maybe I needed that quart to keep cool? I added a quart
> today and it still overheated.

While oil does help cool the engine being a quart low isn't going to
make it overheat.
>
> Fan is wired correctly, although I wonder if and when I get the AC fixed if
> it'll overheat when its on. The PO said he neighbor wired to fan to run at
> all times since it was overheating to begin with.

I figured as much... the Jeep started overheating so the PO tried a
Micky Mouse fix instead of figuring out what was wrong.
>
> Hmm, noticed that the valve cover was leaking a bit of oil, will check the
> head gasket also. I'm assuming it even has the original radiator and I
> heard someone say to replace it after 10 years, well it's been 16 if nobody
> else has.

They all leak oil, it's annoying but usually nothing more than that. My
Jeep ran great for 10 years and 300,000 miles with it's original
radiator, and never overheated except when the water pump went bad or
when I'd flushed out the cooling system and had a big bubble in it.
However when the engine was replaced they found the radiator was pretty
rotten, it not only had lots of rust and stuff in it but it had just
started leaking at one of the tanks.
>
> I'll check up on the things you mention and give ya'll a follow up.
>
> Troy
>
>

The radiators and water pumps aren't that expensive for these beasts.
If it was mine I'd first make sure it didn't have a bad head gasket. If
that was OK and I was planning on keeping it I'd put in a new water
pump, radiator, belts and hoses, and before removing the old parts I'd
give the engine a very through flushing out.

I'd also hook the fan back up properly.

Good luck, looking forward to hear what you find.

Jeff DeWitt

Mike Romain

Your rad system has been modified, badly it would seem...

The old system has no rad cap for the radiator.

If your rad is plugged up with scale no amount of fans is going to help,
it is likely time to flush it out.

Putting power to the secondary fan to make it sort of work implies the
primary fan has failed. This would be a normal failure of the fan
clutch from age.

To test the fan clutch, you get the engine fully warmed up and watch the
fan as someone shuts down the engine. If the fan clutch is working, the
blades will stop spinning almost instantly on hot shut down. If they
continue spinning, you need to replace the fan clutch.

Changing the cap on the overflow bottle has no effect here, but you
could have a bad rad cap. They are a cheap replacement anyway.

If the last owner used the wrong antifreeze mix, it will boil over. I
would check that out for too much antifreeze in the mix.

You can also let it warm up with the rad cap off to watch for smoke
and/or tiny bubbles. If smoke comes out or if it foams up like a washer
with too much soap in it, suspect head gasket.

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)

Troy wrote:
>
> well the 90XJ I have overheated on the way home last night. It was a cool
> evening. Checked it out today, refilled the system w/coolant and it
> overheated again. Previous owner has changed the thermostat already. SO
>
> I was reading about the open and closed systems, and how you can change it
> from the closed it is now to an open system. As it is now the electric fan
> always runs while the key is forward in the ignition (previous owner). Now
> with the closed system it has now, sometimes would a new bottle and cap fix
> the problem? Does the closed system it has now have a fill cap for the
> radiator also cuz this one does, which leads me to think its an open system
> radiator in it already somehow?
>
> Troy

Mike Romain

Your rad system has been modified, badly it would seem...

The old system has no rad cap for the radiator.

If your rad is plugged up with scale no amount of fans is going to help,
it is likely time to flush it out.

Putting power to the secondary fan to make it sort of work implies the
primary fan has failed. This would be a normal failure of the fan
clutch from age.

To test the fan clutch, you get the engine fully warmed up and watch the
fan as someone shuts down the engine. If the fan clutch is working, the
blades will stop spinning almost instantly on hot shut down. If they
continue spinning, you need to replace the fan clutch.

Changing the cap on the overflow bottle has no effect here, but you
could have a bad rad cap. They are a cheap replacement anyway.

If the last owner used the wrong antifreeze mix, it will boil over. I
would check that out for too much antifreeze in the mix.

You can also let it warm up with the rad cap off to watch for smoke
and/or tiny bubbles. If smoke comes out or if it foams up like a washer
with too much soap in it, suspect head gasket.

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)

Troy wrote:
>
> well the 90XJ I have overheated on the way home last night. It was a cool
> evening. Checked it out today, refilled the system w/coolant and it
> overheated again. Previous owner has changed the thermostat already. SO
>
> I was reading about the open and closed systems, and how you can change it
> from the closed it is now to an open system. As it is now the electric fan
> always runs while the key is forward in the ignition (previous owner). Now
> with the closed system it has now, sometimes would a new bottle and cap fix
> the problem? Does the closed system it has now have a fill cap for the
> radiator also cuz this one does, which leads me to think its an open system
> radiator in it already somehow?
>
> Troy

Mike Romain

Your rad system has been modified, badly it would seem...

The old system has no rad cap for the radiator.

If your rad is plugged up with scale no amount of fans is going to help,
it is likely time to flush it out.

Putting power to the secondary fan to make it sort of work implies the
primary fan has failed. This would be a normal failure of the fan
clutch from age.

To test the fan clutch, you get the engine fully warmed up and watch the
fan as someone shuts down the engine. If the fan clutch is working, the
blades will stop spinning almost instantly on hot shut down. If they
continue spinning, you need to replace the fan clutch.

Changing the cap on the overflow bottle has no effect here, but you
could have a bad rad cap. They are a cheap replacement anyway.

If the last owner used the wrong antifreeze mix, it will boil over. I
would check that out for too much antifreeze in the mix.

You can also let it warm up with the rad cap off to watch for smoke
and/or tiny bubbles. If smoke comes out or if it foams up like a washer
with too much soap in it, suspect head gasket.

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)

Troy wrote:
>
> well the 90XJ I have overheated on the way home last night. It was a cool
> evening. Checked it out today, refilled the system w/coolant and it
> overheated again. Previous owner has changed the thermostat already. SO
>
> I was reading about the open and closed systems, and how you can change it
> from the closed it is now to an open system. As it is now the electric fan
> always runs while the key is forward in the ignition (previous owner). Now
> with the closed system it has now, sometimes would a new bottle and cap fix
> the problem? Does the closed system it has now have a fill cap for the
> radiator also cuz this one does, which leads me to think its an open system
> radiator in it already somehow?
>
> Troy

Troy

This thing must be whacked out real good....
I looked around other posts in the past about this issue, checked out my fan
clutch and it would stop spinning almost immediately while cold, but when
the engine warmed up it spins quite more than when it was cold... replaced
it and everything is running cool! Although, before I was trying to track
down a blinker issue; they would come on but not blink. Now the freakin
blinkers work too? I think I must have jiggled some wires while wrestling
with the fan...

Troy

Oh I have other issues about the xj i'm gonna post in a new thread!