XJ open/closed cooling system
 

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

Re: XJ open/closed cooling system
 

Hi Troy,
The closed coolant system is the reason you don't see any Renaults
on the road. If it's cold, pull the top radiator hose to see if you have
coolant on that side. If so go ahead and replace the thermostat, many go
bad from new. If filling the system with a new thermostat fixes your
problem, then I would convert the the closed system to one like we use
now, the radiator cap is pressurized and the side tank is just a holding
reservoir. Then begin to check it's level like you chick your oil.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

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

Re: XJ open/closed cooling system
 

Hi Troy,
The closed coolant system is the reason you don't see any Renaults
on the road. If it's cold, pull the top radiator hose to see if you have
coolant on that side. If so go ahead and replace the thermostat, many go
bad from new. If filling the system with a new thermostat fixes your
problem, then I would convert the the closed system to one like we use
now, the radiator cap is pressurized and the side tank is just a holding
reservoir. Then begin to check it's level like you chick your oil.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

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

Re: XJ open/closed cooling system
 

Hi Troy,
The closed coolant system is the reason you don't see any Renaults
on the road. If it's cold, pull the top radiator hose to see if you have
coolant on that side. If so go ahead and replace the thermostat, many go
bad from new. If filling the system with a new thermostat fixes your
problem, then I would convert the the closed system to one like we use
now, the radiator cap is pressurized and the side tank is just a holding
reservoir. Then begin to check it's level like you chick your oil.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

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

Re: XJ open/closed cooling system
 

Couple of thoughts... first I assume you are sure it really did overheat
and it isn't just the gage going up?

Second, I've had problems with air lock after changing the coolant. If
there is air blocking a hose it's going to overheat. One of those flush
and fill kits solved that.

Third, the PO did odd things with the fan, might he have hooked it up
backwards? A lot (all?) of those fans will work fine as either pushers
or pullers, but if it's hooked up backward it won't cool your radiator.

Forth, with the engine hot and off run your hand over the radiator
feeling for hot and cool spots. The whole radiator should be about the
same temp, if you find cool spots then you've got a clogged radiator.

Fifth, you might check the dip stick for any signs of foaming in the oil
or rust on the dip sick. If you've got a blown head gasket it's gonna
overheat no matter what else you do.

Of course you also want to make sure your belt and hoses are in good
shape. A lower hose can look fine but collapse at speed and cause the
engine to overheat, and of course a slipping belt can cause the water
pump to not pump at capacity and could cause overheating.

Good luck!

Jeff DeWitt

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
>
>

Re: XJ open/closed cooling system
 

Couple of thoughts... first I assume you are sure it really did overheat
and it isn't just the gage going up?

Second, I've had problems with air lock after changing the coolant. If
there is air blocking a hose it's going to overheat. One of those flush
and fill kits solved that.

Third, the PO did odd things with the fan, might he have hooked it up
backwards? A lot (all?) of those fans will work fine as either pushers
or pullers, but if it's hooked up backward it won't cool your radiator.

Forth, with the engine hot and off run your hand over the radiator
feeling for hot and cool spots. The whole radiator should be about the
same temp, if you find cool spots then you've got a clogged radiator.

Fifth, you might check the dip stick for any signs of foaming in the oil
or rust on the dip sick. If you've got a blown head gasket it's gonna
overheat no matter what else you do.

Of course you also want to make sure your belt and hoses are in good
shape. A lower hose can look fine but collapse at speed and cause the
engine to overheat, and of course a slipping belt can cause the water
pump to not pump at capacity and could cause overheating.

Good luck!

Jeff DeWitt

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
>
>

Re: XJ open/closed cooling system
 

Couple of thoughts... first I assume you are sure it really did overheat
and it isn't just the gage going up?

Second, I've had problems with air lock after changing the coolant. If
there is air blocking a hose it's going to overheat. One of those flush
and fill kits solved that.

Third, the PO did odd things with the fan, might he have hooked it up
backwards? A lot (all?) of those fans will work fine as either pushers
or pullers, but if it's hooked up backward it won't cool your radiator.

Forth, with the engine hot and off run your hand over the radiator
feeling for hot and cool spots. The whole radiator should be about the
same temp, if you find cool spots then you've got a clogged radiator.

Fifth, you might check the dip stick for any signs of foaming in the oil
or rust on the dip sick. If you've got a blown head gasket it's gonna
overheat no matter what else you do.

Of course you also want to make sure your belt and hoses are in good
shape. A lower hose can look fine but collapse at speed and cause the
engine to overheat, and of course a slipping belt can cause the water
pump to not pump at capacity and could cause overheating.

Good luck!

Jeff DeWitt

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
>
>

Re: XJ open/closed cooling system
 

Bill,

The reason you don't see Renaults on the road, is that this is not Europe.

A fan that always runs, is a fan that is going to burn out soon.

Earle

"L.W.(Bill) ------ III" <----------@cox.net> wrote in message
news:44679E81.C480ACD@cox.net...
> Hi Troy,
> The closed coolant system is the reason you don't see any Renaults
> on the road. If it's cold, pull the top radiator hose to see if you have
> coolant on that side. If so go ahead and replace the thermostat, many go
> bad from new. If filling the system with a new thermostat fixes your
> problem, then I would convert the the closed system to one like we use
> now, the radiator cap is pressurized and the side tank is just a holding
> reservoir. Then begin to check it's level like you chick your oil.
> God Bless America, Bill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> 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

Re: XJ open/closed cooling system
 

Bill,

The reason you don't see Renaults on the road, is that this is not Europe.

A fan that always runs, is a fan that is going to burn out soon.

Earle

"L.W.(Bill) ------ III" <----------@cox.net> wrote in message
news:44679E81.C480ACD@cox.net...
> Hi Troy,
> The closed coolant system is the reason you don't see any Renaults
> on the road. If it's cold, pull the top radiator hose to see if you have
> coolant on that side. If so go ahead and replace the thermostat, many go
> bad from new. If filling the system with a new thermostat fixes your
> problem, then I would convert the the closed system to one like we use
> now, the radiator cap is pressurized and the side tank is just a holding
> reservoir. Then begin to check it's level like you chick your oil.
> God Bless America, Bill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> 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

Re: XJ open/closed cooling system
 

Bill,

The reason you don't see Renaults on the road, is that this is not Europe.

A fan that always runs, is a fan that is going to burn out soon.

Earle

"L.W.(Bill) ------ III" <----------@cox.net> wrote in message
news:44679E81.C480ACD@cox.net...
> Hi Troy,
> The closed coolant system is the reason you don't see any Renaults
> on the road. If it's cold, pull the top radiator hose to see if you have
> coolant on that side. If so go ahead and replace the thermostat, many go
> bad from new. If filling the system with a new thermostat fixes your
> problem, then I would convert the the closed system to one like we use
> now, the radiator cap is pressurized and the side tank is just a holding
> reservoir. Then begin to check it's level like you chick your oil.
> God Bless America, Bill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> 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