Auxiliary fans in front of the radiator?

[winkosmosis]

The problem is I can't do the draining etc myself because my lease forbids it. I don't like messing with those chemicals anyway. I also just moved from TX to Hawaii and I didn't bring many tools. I'm guessing shipping here would cost about $100 for something as big as a radiator anyway so I'll keep the stocker for now

 

[winkosmosis]

Well I took it to Sears. They checked the thermostat and said it was OK, then the guy took it for a test drive and it was running warm. The counter guy said it seemed like the tstat wasn't opening all the way, so they recommended flushing and replacing the tstat which is what I planned on doing anyway. So I had them do that and also got the radiator cap replaced. $193 total.

It's still running hot, maybe even worse than before! In the afternoon sun it hit 225 at a stop light. When moving it was more like 216. When I turned off the AC it went down to 207.

I'm not surprised it's worse than before since there may be bubbles in the system, but from reading on NAXJA it looks like they work themselves out in an open cooling system. But the fact that I'm sitting still makes it get hotter, just like before, makes me think it's an airflow problem. I forgot to check the aux fan but I'll do that tomorrow.

 

[alexfm]

Well I took it to Sears. They checked the thermostat and said it was OK, then the guy took it for a test drive and it was running warm. The counter guy said it seemed like the tstat wasn't opening all the way, so they recommended flushing and replacing the tstat which is what I planned on doing anyway. So I had them do that and also got the radiator cap replaced. $193 total.

It's still running hot, maybe even worse than before! In the afternoon sun it hit 225 at a stop light. When moving it was more like 216. When I turned off the AC it went down to 207.

I'm not surprised it's worse than before since there may be bubbles in the system, but from reading on NAXJA it looks like they work themselves out in an open cooling system. But the fact that I'm sitting still makes it get hotter, just like before, makes me think it's an airflow problem. I forgot to check the aux fan but I'll do that tomorrow.

Im havin a very similar problem with my XJ. It runs hot all the time, and although I dont have a Scangauge or anything that tells me exactly how how, its usually sitting on or near the line right before the red on the water temp gauge. Im not sure what the problem with mine is, I dont use the AC (it doesnt work anyway), but my dad told me that not having a fan-shroud is a big part of it. 100+ degrees almost everyday hasnt been much help either.

 

[R_Lefebvre]

Where's your fan shroud? Yes, that's a HUGE deal, especially when not moving.

 

[winkosmosis]

Im havin a very similar problem with my XJ. It runs hot all the time, and although I dont have a Scangauge or anything that tells me exactly how how, its usually sitting on or near the line right before the red on the water temp gauge. Im not sure what the problem with mine is, I dont use the AC (it doesnt work anyway), but my dad told me that not having a fan-shroud is a big part of it. 100+ degrees almost everyday hasnt been much help either.

That's a lot hotter. My gauge is still on the 210 mark when the actual temp is 225.

 

[winkosmosis]

Today, with some really slow stop and go (letting tourists cross the street in Lahaina) it got up to 238F according to the Scanguage. Intake air temp was 158F!!! So I was sure one of the fans had not be working, otherwise how could the temp under the hood get so high? But when I got home I checked, and both fans were spinning.

On the highway between 40 and 50mph, the temps were 210-220.

 

[winkosmosis]

There is one difference between now and last summer in Texas when it didn't overheat even in 90-95F weather. I have a front skid plate now. Could the restriction be making it harder for the fans to push air through the engine bay?

 

[baca327]

That may be restricting airflow. They may have left some air in the system, which would cause it to be worse now. Try letting it run with the heater on high just idling till vehicle warms up. That skid plate may be causing the fans to work harder especially parked or at a stoplight. Try driving it for a day with no skid plate see how your temps fare. As stated before make sure the fins are clean, no mud stuck in between them.

 

[winkosmosis]

I'd try taking off the skid plate but I don't have anyone to help lift it back into place. Will wash the fins tomorrow but they look pretty clean. Just some bugs stuck in them. It's not like I've done a lot of driving through dust.
I really want to add some fans. Whatever the problem is, airflow seems to be the solution to the heat. :campfire:Are there any decent cheap fans that are small enough to fit into the 3 gaps of the fascia once you remove the 7 slot grill?

 

[baca327]

I'd try taking off the skid plate but I don't have anyone to help lift it back into place. Will wash the fins tomorrow but they look pretty clean. Just some bugs stuck in them. It's not like I've done a lot of driving through dust.
I really want to add some fans. Whatever the problem is, airflow seems to be the solution to the heat. :campfire:Are there any decent cheap fans that are small enough to fit into the 3 gaps of the fascia once you remove the 7 slot grill?

If your looking for an aux fan your best bet is to upgrade your current fans to add more. Also hood vents alleviate some of the heat during idle at a stop. Sounds like by adding the skid plate its blocking air flow. You need to compensate that by moving air more with less work. Opening up area to vent the hot air and adding better fans. Alot of folks usually replace the viscous fan with an electric.

 

[winkosmosis]

The problem is those options are much more difficult - plumbing for at thermostat, cutting for vents, fabricating for either -and require finding a shop to do the work.
If I took my XJ here http://www.mauioffroad.com I might get it back with 30x15.5" Super Swampers and chrome bling everywhere.

Also, an efan might not be such a good idea on this island. Most driving is at low speed, so it would be running constantly, negating the efficiency bonus. I was thinking last night, if you're at idle speed a lot so the alternator isn't generating much power, wouldn't the battery just get used a lot and worn down faster than normal? It's like you're hybridizing your cooling system with a battery meant for starting.

 

[bobDog]

XJs have 2 fans....one is mechanical one electric. be sure the electric comes on when you turn on the AC or the defrost. If not get a new sensor. The mechanical has a viscous clutch.....that clutch can start failing w/o you knowing. Drive till you have the engine hot. turn off and see if you can spin the fan by hand....if so you need a new clutch. Replace w/ a grand cherokee clutch from a unit w/o the tow package and you will also gain cooling performance.:victory:

 

[winkosmosis]

OK, I'll try seeing if I can spin it by hand when it's hot.

On a 1999 the efan is controlled by the computer based on temperature and mine does spin at 220F

 

[baca327]

The problem is those options are much more difficult - plumbing for at thermostat, cutting for vents, fabricating for either -and require finding a shop to do the work.
If I took my XJ here http://www.mauioffroad.com I might get it back with 30x15.5" Super Swampers and chrome bling everywhere.

Also, an efan might not be such a good idea on this island. Most driving is at low speed, so it would be running constantly, negating the efficiency bonus. I was thinking last night, if you're at idle speed a lot so the alternator isn't generating much power, wouldn't the battery just get used a lot and worn down faster than normal? It's like you're hybridizing your cooling system with a battery meant for starting.

Depending on the condition on your voltage regulator your alternator produces the same amount of power throughout the RPM range. There is a electro-magnet in your alternator and the slower it spins the more power is sent to it conducting more voltage and amps. While the engine is running your using the alternator, your battery acts more or less like a voltage buffer absorbing most of the voltage spikes in the system. Your wearing out your battery if you have a short directly to it or everytime you start your engine. Hope that makes sense. Nice thing about e-fans is you can wire them to switch also so you can turn them on before the ecm decides its too hot or you could use it to disable it during any fording. Hope this helps. Also if your engine gets hot during low speed your mechanical will be running anyway causing parasitic drag on the crank resulting in worse fuel mileage.

 

[winkosmosis]

Depending on the condition on your voltage regulator your alternator produces the same amount of power throughout the RPM range. There is a electro-magnet in your alternator and the slower it spins the more power is sent to it conducting more voltage and amps. While the engine is running your using the alternator, your battery acts more or less like a voltage buffer absorbing most of the voltage spikes in the system. Your wearing out your battery if you have a short directly to it or everytime you start your engine. Hope that makes sense. Nice thing about e-fans is you can wire them to switch also so you can turn them on before the ecm decides its too hot or you could use it to disable it during any fording. Hope this helps. Also if your engine gets hot during low speed your mechanical will be running anyway causing parasitic drag on the crank resulting in worse fuel mileage.

Hmmm I guess there is a big benefit in being able to run at full speed even when the engine is only idling. Too bad it would probably be near impossible to find one of those Taurus fans here. I haven't even seen a Taurus on Maui. Everybody drives Tacomas an 4Runners... maybe there is a Toyota product that could be swapped in.

Still though, for $150 for a new fan + cost of plumbing the system for a thermostat + having someone properly mount it, it would get expensive.