I've got a '96 Jeep Cherokee 4.0L with 100k miles. I live in Las Vegas and
spend months driving in 90-100+ temps (I've seen 120+ a few times), often
off-road on grades at relatively low speeds.

Over the past two years the jeep has begun to climb up to the 240 degree
mark on the thermostat and not come back down unless I turn it off and wait
a while. Knowing the neglect I've put on the vehicle, I just put in a new 3
core radiator, a high flow water pump, and a new 195 thermostat, along with
flushing the whole system with some prestone product. I also put in an
electric fan in replace of the mechanical fan (I'm still debating weather
this was a dumb idea.)

Nonetheless the vehicle can now hold steady between 210-215 in 90+ temps
with the AC on and the vehicle stopped. It still seems a bit high.

My question is, ignoring the actual cooling components what engine parts
could cause my engine itself to generate more heat? I've never done much
with my fuel/exhaust system. I've got all original sensors (o2 etc..) and
never used fuel injector cleaner. I've begun noticing a loss in fuel
economy along with the heat problem and it does seem to idle a little
rougher then when she was younger.

Any thoughts would be appreciated.

Thanks,

Matt

 

Well... I would guess the clutch on your original mechanical fan wore
out.

You are describing the symptoms perfectly....

It is a cheap easy repair....

You have a 195 t-stat, running at 200 to 220 is perfectly normal in hot
weather.

s wrote:
>
> I've got a '96 Jeep Cherokee 4.0L with 100k miles. I live in Las Vegas and
> spend months driving in 90-100+ temps (I've seen 120+ a few times), often
> off-road on grades at relatively low speeds.
>
> Over the past two years the jeep has begun to climb up to the 240 degree
> mark on the thermostat and not come back down unless I turn it off and wait
> a while. Knowing the neglect I've put on the vehicle, I just put in a new 3
> core radiator, a high flow water pump, and a new 195 thermostat, along with
> flushing the whole system with some prestone product. I also put in an
> electric fan in replace of the mechanical fan (I'm still debating weather
> this was a dumb idea.)
>
> Nonetheless the vehicle can now hold steady between 210-215 in 90+ temps
> with the AC on and the vehicle stopped. It still seems a bit high.
>
> My question is, ignoring the actual cooling components what engine parts
> could cause my engine itself to generate more heat? I've never done much
> with my fuel/exhaust system. I've got all original sensors (o2 etc..) and
> never used fuel injector cleaner. I've begun noticing a loss in fuel
> economy along with the heat problem and it does seem to idle a little
> rougher then when she was younger.
>
> Any thoughts would be appreciated.
>
> Thanks,
>
> Matt

 

Well... I would guess the clutch on your original mechanical fan wore
out.

You are describing the symptoms perfectly....

It is a cheap easy repair....

You have a 195 t-stat, running at 200 to 220 is perfectly normal in hot
weather.

s wrote:
>
> I've got a '96 Jeep Cherokee 4.0L with 100k miles. I live in Las Vegas and
> spend months driving in 90-100+ temps (I've seen 120+ a few times), often
> off-road on grades at relatively low speeds.
>
> Over the past two years the jeep has begun to climb up to the 240 degree
> mark on the thermostat and not come back down unless I turn it off and wait
> a while. Knowing the neglect I've put on the vehicle, I just put in a new 3
> core radiator, a high flow water pump, and a new 195 thermostat, along with
> flushing the whole system with some prestone product. I also put in an
> electric fan in replace of the mechanical fan (I'm still debating weather
> this was a dumb idea.)
>
> Nonetheless the vehicle can now hold steady between 210-215 in 90+ temps
> with the AC on and the vehicle stopped. It still seems a bit high.
>
> My question is, ignoring the actual cooling components what engine parts
> could cause my engine itself to generate more heat? I've never done much
> with my fuel/exhaust system. I've got all original sensors (o2 etc..) and
> never used fuel injector cleaner. I've begun noticing a loss in fuel
> economy along with the heat problem and it does seem to idle a little
> rougher then when she was younger.
>
> Any thoughts would be appreciated.
>
> Thanks,
>
> Matt

 

On Fri, 12 Sep 2003 22:02:02 UTC "s" <a> wrote:

> I've got a '96 Jeep Cherokee 4.0L with 100k miles. I live in Las Vegas and
> spend months driving in 90-100+ temps (I've seen 120+ a few times), often
> off-road on grades at relatively low speeds.
>
> Over the past two years the jeep has begun to climb up to the 240 degree
> mark on the thermostat and not come back down unless I turn it off and wait
> a while. Knowing the neglect I've put on the vehicle, I just put in a new 3
> core radiator, a high flow water pump, and a new 195 thermostat, along with
> flushing the whole system with some prestone product. I also put in an
> electric fan in replace of the mechanical fan (I'm still debating weather
> this was a dumb idea.)
>
> Nonetheless the vehicle can now hold steady between 210-215 in 90+ temps
> with the AC on and the vehicle stopped. It still seems a bit high.
>
> My question is, ignoring the actual cooling components what engine parts
> could cause my engine itself to generate more heat? I've never done much
> with my fuel/exhaust system. I've got all original sensors (o2 etc..) and
> never used fuel injector cleaner. I've begun noticing a loss in fuel
> economy along with the heat problem and it does seem to idle a little
> rougher then when she was younger.
>
> Any thoughts would be appreciated.

The old system was slowly plugging up and losing efficiency, but the
electric fan doesn't have the power of the mechanical fan by a long
shot. A better idea would have been an electric fan in addition to
the mechanical fan. I suspect that just putting the mechanical fan
back in (assuming the fan clutch is OK) will solve most of the
problem.

--
Will Honea <whonea@codenet.net>

 

On Fri, 12 Sep 2003 22:02:02 UTC "s" <a> wrote:

> I've got a '96 Jeep Cherokee 4.0L with 100k miles. I live in Las Vegas and
> spend months driving in 90-100+ temps (I've seen 120+ a few times), often
> off-road on grades at relatively low speeds.
>
> Over the past two years the jeep has begun to climb up to the 240 degree
> mark on the thermostat and not come back down unless I turn it off and wait
> a while. Knowing the neglect I've put on the vehicle, I just put in a new 3
> core radiator, a high flow water pump, and a new 195 thermostat, along with
> flushing the whole system with some prestone product. I also put in an
> electric fan in replace of the mechanical fan (I'm still debating weather
> this was a dumb idea.)
>
> Nonetheless the vehicle can now hold steady between 210-215 in 90+ temps
> with the AC on and the vehicle stopped. It still seems a bit high.
>
> My question is, ignoring the actual cooling components what engine parts
> could cause my engine itself to generate more heat? I've never done much
> with my fuel/exhaust system. I've got all original sensors (o2 etc..) and
> never used fuel injector cleaner. I've begun noticing a loss in fuel
> economy along with the heat problem and it does seem to idle a little
> rougher then when she was younger.
>
> Any thoughts would be appreciated.

The old system was slowly plugging up and losing efficiency, but the
electric fan doesn't have the power of the mechanical fan by a long
shot. A better idea would have been an electric fan in addition to
the mechanical fan. I suspect that just putting the mechanical fan
back in (assuming the fan clutch is OK) will solve most of the
problem.

--
Will Honea <whonea@codenet.net>

 

On Fri, 12 Sep 2003 23:22:47 UTC "s" <a> wrote:

> I would like info on the engine portion of the question. But in regards to
> the electri fan I've got some questions. First as I wrote in the original
> post, I too don't know if its a good idea either but...
>
> First cost wise: I broke the fan shroud getting it off, so that plus a new
> clutch is about $70.00. I got the electric fan for $80.00 from a friend
> (flex-a-lite 110.)

Mine's an 88 - anything plastic is getting brittle by now so I just
expect to break things like that when I pull them. I keep a sheet of
16-18 guage galvanized steel in the garage so that if something
cracks I just cut a patch of steel, gunk it up with Automotive GOOP
and pop-rivet the thing back together. Adds character to the beast.
Seriously, no piddly-assed little electric motor is going to pull the
air that the mechanical one will. I figure that the aux fan on mine
is just that, a little help whe needed. It can be unplugged and I
never miss it. It's all about the volume of air you put thru the
radiator.

> I figured it was worth a try for the following reasons:
>
> 1.) The car only heats up at low speeds, above 40 or so it ram cools just
> fine as long as I'm under 2500rpm. Will the fan, which runs at a higher
> speed then the mechanical fan at idle, cool better in these conditions
> despite lower cfm rating?

See above - it's CFM that counts in the end.

>
> 2.) Mud and water crossings, It's kinda nice to be able to turn the thing
> off and not have mud pushed into the engine bay. (When it rains here, it
> floods.)

Now there you have a point.

> 3.) Noise level. When both fans are off (I do have the factory aux fan.) the
> thing is so quite that when I first tried it out I thought I stalled at an
> intersection.
>
> Anywhen have thoughts on these items?

At my age, noise has ceased to be a major problem - after over 4000
hours flying jets I could frequently use an ear trumpet, anyway.

> My decesion will be made this weekend: Saturday a slow 15 mile steep offroad
> climp 85-95 outside temp. Sunday: a long road trip 95-105 temp with 7-10%
> grades at highway speeds.
>
> Let me know,

I ran mine all over West Texas, last summer especially, 25-30 kt
headwinds and 100+ temps with the A/C going full bore and never saw
the guage get above the center mark even when I forgot to plug the aux
fan back in after I had it off to swap the serp belt. I was also
hauling some heavy loads around the farm pulling 6-8 tons on a flatbed
in 4LO. Best I recall, there was one day that we hauled over 100 tons
total up the hill from the back field to the dock - about a mile each
way - and it ran rock solid there as well. The only time I've ever
seen mine above the center mark on the guage was last weekend pulling
long grades at 10-12,000 feet in 3rd (damned 3.07 diffs!) and it was
either on or just barely above the line. That's with the original (at
least the original style) 2-core radiator in this miserable closed
system they used back then. I wouldn't think twice about replacing
the clutch versus an electric myself.


--
Will Honea <whonea@codenet.net>

 

On Fri, 12 Sep 2003 23:22:47 UTC "s" <a> wrote:

> I would like info on the engine portion of the question. But in regards to
> the electri fan I've got some questions. First as I wrote in the original
> post, I too don't know if its a good idea either but...
>
> First cost wise: I broke the fan shroud getting it off, so that plus a new
> clutch is about $70.00. I got the electric fan for $80.00 from a friend
> (flex-a-lite 110.)

Mine's an 88 - anything plastic is getting brittle by now so I just
expect to break things like that when I pull them. I keep a sheet of
16-18 guage galvanized steel in the garage so that if something
cracks I just cut a patch of steel, gunk it up with Automotive GOOP
and pop-rivet the thing back together. Adds character to the beast.
Seriously, no piddly-assed little electric motor is going to pull the
air that the mechanical one will. I figure that the aux fan on mine
is just that, a little help whe needed. It can be unplugged and I
never miss it. It's all about the volume of air you put thru the
radiator.

> I figured it was worth a try for the following reasons:
>
> 1.) The car only heats up at low speeds, above 40 or so it ram cools just
> fine as long as I'm under 2500rpm. Will the fan, which runs at a higher
> speed then the mechanical fan at idle, cool better in these conditions
> despite lower cfm rating?

See above - it's CFM that counts in the end.

>
> 2.) Mud and water crossings, It's kinda nice to be able to turn the thing
> off and not have mud pushed into the engine bay. (When it rains here, it
> floods.)

Now there you have a point.

> 3.) Noise level. When both fans are off (I do have the factory aux fan.) the
> thing is so quite that when I first tried it out I thought I stalled at an
> intersection.
>
> Anywhen have thoughts on these items?

At my age, noise has ceased to be a major problem - after over 4000
hours flying jets I could frequently use an ear trumpet, anyway.

> My decesion will be made this weekend: Saturday a slow 15 mile steep offroad
> climp 85-95 outside temp. Sunday: a long road trip 95-105 temp with 7-10%
> grades at highway speeds.
>
> Let me know,

I ran mine all over West Texas, last summer especially, 25-30 kt
headwinds and 100+ temps with the A/C going full bore and never saw
the guage get above the center mark even when I forgot to plug the aux
fan back in after I had it off to swap the serp belt. I was also
hauling some heavy loads around the farm pulling 6-8 tons on a flatbed
in 4LO. Best I recall, there was one day that we hauled over 100 tons
total up the hill from the back field to the dock - about a mile each
way - and it ran rock solid there as well. The only time I've ever
seen mine above the center mark on the guage was last weekend pulling
long grades at 10-12,000 feet in 3rd (damned 3.07 diffs!) and it was
either on or just barely above the line. That's with the original (at
least the original style) 2-core radiator in this miserable closed
system they used back then. I wouldn't think twice about replacing
the clutch versus an electric myself.


--
Will Honea <whonea@codenet.net>

 

Well I didn't even get to the second day of testing. Mid way through my
offroad trip saturday I had to pull off the trail because the Jeep was
getting up around 240. Turns out the electric fan blades had made contact
with the radiator housing and bent over a few blades and was now stalled.
In retrospect I think it probably happened fairly earlier in the drive. I
think its a testament to the other components in the cooling system that I
made it as far as I did. This was during a 9 mi 7%-9% grade with tons of
big rocks and ruts to negotiate very slowly.

I ended up hooking up my aux. electric fan to come on at 195 (like the main
fan would.) With just this fan I made it up the last .5 mile of the climb
and the 100miles back to town without ever going over 215.

I guess its time to put the mechanical fan back on.

Matt

"s" <a> wrote in message news:kwidnc2eVcnTyP-iXTWJlg@mpowercom.net...
> I would like info on the engine portion of the question. But in regards
to
> the electri fan I've got some questions. First as I wrote in the original
> post, I too don't know if its a good idea either but...
>
> First cost wise: I broke the fan shroud getting it off, so that plus a new
> clutch is about $70.00. I got the electric fan for $80.00 from a friend
> (flex-a-lite 110.)
>
> I figured it was worth a try for the following reasons:
>
> 1.) The car only heats up at low speeds, above 40 or so it ram cools just
> fine as long as I'm under 2500rpm. Will the fan, which runs at a higher
> speed then the mechanical fan at idle, cool better in these conditions
> despite lower cfm rating?
>
> 2.) Mud and water crossings, It's kinda nice to be able to turn the thing
> off and not have mud pushed into the engine bay. (When it rains here, it
> floods.)
>
> 3.) Noise level. When both fans are off (I do have the factory aux fan.)
the
> thing is so quite that when I first tried it out I thought I stalled at an
> intersection.
>
> Anywhen have thoughts on these items?
>
> My decesion will be made this weekend: Saturday a slow 15 mile steep
offroad
> climp 85-95 outside temp. Sunday: a long road trip 95-105 temp with 7-10%
> grades at highway speeds.
>
> Let me know,
>
> Matt
>
>
>
> "Will Honea" <whonea@codenet.net> wrote in message
> news:JxX2tWiP5BNp-pn2-21UIdUWrKgnE@anon.none.net...
> > On Fri, 12 Sep 2003 22:02:02 UTC "s" <a> wrote:
> >
> > > I've got a '96 Jeep Cherokee 4.0L with 100k miles. I live in Las
Vegas
> and
> > > spend months driving in 90-100+ temps (I've seen 120+ a few times),
> often
> > > off-road on grades at relatively low speeds.
> > >
> > > Over the past two years the jeep has begun to climb up to the 240
degree
> > > mark on the thermostat and not come back down unless I turn it off and
> wait
> > > a while. Knowing the neglect I've put on the vehicle, I just put in a
> new 3
> > > core radiator, a high flow water pump, and a new 195 thermostat, along
> with
> > > flushing the whole system with some prestone product. I also put in
an
> > > electric fan in replace of the mechanical fan (I'm still debating
> weather
> > > this was a dumb idea.)
> > >
> > > Nonetheless the vehicle can now hold steady between 210-215 in 90+
temps
> > > with the AC on and the vehicle stopped. It still seems a bit high.
> > >
> > > My question is, ignoring the actual cooling components what engine
parts
> > > could cause my engine itself to generate more heat? I've never done
> much
> > > with my fuel/exhaust system. I've got all original sensors (o2 etc..)
> and
> > > never used fuel injector cleaner. I've begun noticing a loss in fuel
> > > economy along with the heat problem and it does seem to idle a little
> > > rougher then when she was younger.
> > >
> > > Any thoughts would be appreciated.
> >
> > The old system was slowly plugging up and losing efficiency, but the
> > electric fan doesn't have the power of the mechanical fan by a long
> > shot. A better idea would have been an electric fan in addition to
> > the mechanical fan. I suspect that just putting the mechanical fan
> > back in (assuming the fan clutch is OK) will solve most of the
> > problem.
> >
> > --
> > Will Honea <whonea@codenet.net>
>
>

 

Well I didn't even get to the second day of testing. Mid way through my
offroad trip saturday I had to pull off the trail because the Jeep was
getting up around 240. Turns out the electric fan blades had made contact
with the radiator housing and bent over a few blades and was now stalled.
In retrospect I think it probably happened fairly earlier in the drive. I
think its a testament to the other components in the cooling system that I
made it as far as I did. This was during a 9 mi 7%-9% grade with tons of
big rocks and ruts to negotiate very slowly.

I ended up hooking up my aux. electric fan to come on at 195 (like the main
fan would.) With just this fan I made it up the last .5 mile of the climb
and the 100miles back to town without ever going over 215.

I guess its time to put the mechanical fan back on.

Matt

"s" <a> wrote in message news:kwidnc2eVcnTyP-iXTWJlg@mpowercom.net...
> I would like info on the engine portion of the question. But in regards
to
> the electri fan I've got some questions. First as I wrote in the original
> post, I too don't know if its a good idea either but...
>
> First cost wise: I broke the fan shroud getting it off, so that plus a new
> clutch is about $70.00. I got the electric fan for $80.00 from a friend
> (flex-a-lite 110.)
>
> I figured it was worth a try for the following reasons:
>
> 1.) The car only heats up at low speeds, above 40 or so it ram cools just
> fine as long as I'm under 2500rpm. Will the fan, which runs at a higher
> speed then the mechanical fan at idle, cool better in these conditions
> despite lower cfm rating?
>
> 2.) Mud and water crossings, It's kinda nice to be able to turn the thing
> off and not have mud pushed into the engine bay. (When it rains here, it
> floods.)
>
> 3.) Noise level. When both fans are off (I do have the factory aux fan.)
the
> thing is so quite that when I first tried it out I thought I stalled at an
> intersection.
>
> Anywhen have thoughts on these items?
>
> My decesion will be made this weekend: Saturday a slow 15 mile steep
offroad
> climp 85-95 outside temp. Sunday: a long road trip 95-105 temp with 7-10%
> grades at highway speeds.
>
> Let me know,
>
> Matt
>
>
>
> "Will Honea" <whonea@codenet.net> wrote in message
> news:JxX2tWiP5BNp-pn2-21UIdUWrKgnE@anon.none.net...
> > On Fri, 12 Sep 2003 22:02:02 UTC "s" <a> wrote:
> >
> > > I've got a '96 Jeep Cherokee 4.0L with 100k miles. I live in Las
Vegas
> and
> > > spend months driving in 90-100+ temps (I've seen 120+ a few times),
> often
> > > off-road on grades at relatively low speeds.
> > >
> > > Over the past two years the jeep has begun to climb up to the 240
degree
> > > mark on the thermostat and not come back down unless I turn it off and
> wait
> > > a while. Knowing the neglect I've put on the vehicle, I just put in a
> new 3
> > > core radiator, a high flow water pump, and a new 195 thermostat, along
> with
> > > flushing the whole system with some prestone product. I also put in
an
> > > electric fan in replace of the mechanical fan (I'm still debating
> weather
> > > this was a dumb idea.)
> > >
> > > Nonetheless the vehicle can now hold steady between 210-215 in 90+
temps
> > > with the AC on and the vehicle stopped. It still seems a bit high.
> > >
> > > My question is, ignoring the actual cooling components what engine
parts
> > > could cause my engine itself to generate more heat? I've never done
> much
> > > with my fuel/exhaust system. I've got all original sensors (o2 etc..)
> and
> > > never used fuel injector cleaner. I've begun noticing a loss in fuel
> > > economy along with the heat problem and it does seem to idle a little
> > > rougher then when she was younger.
> > >
> > > Any thoughts would be appreciated.
> >
> > The old system was slowly plugging up and losing efficiency, but the
> > electric fan doesn't have the power of the mechanical fan by a long
> > shot. A better idea would have been an electric fan in addition to
> > the mechanical fan. I suspect that just putting the mechanical fan
> > back in (assuming the fan clutch is OK) will solve most of the
> > problem.
> >
> > --
> > Will Honea <whonea@codenet.net>
>
>

 

I think I am driving in one of the most hostile deserts in the world.
Driving grades in 125 temps in and out of Death Valley and elsewhere in the
Mojave can be awfully hard on a car (and a driver.)

Matt

"Dave Milne" <jeep@_nospam_milne.info> wrote in message
news:VE09b.10187$Vc.90092675@news-text.cableinet.net...
> from the Kenlowe advert:
>
> "your go anywhere 4x4 has cooling designed for the most hostile deserts in
> the world. So its not surprising that only one in a milliom owners
actually
> need the oversize viscous engine driven fan ... replace your viscous fan
> with a thermo electric Kenlowe fan to save fuel .. " and blah blah blah.
>
> In other words, it doesn't work...
>
> --
> Dave Milne, Scotland
> '99 TJ 4.0 Sahara
>
> "mpower" <a@a.com> wrote in message
> news:SO2dnQje9voCCfmiXTWJiA@mpowercom.net...
> : I guess its time to put the mechanical fan back on.
>
>