Does anyone have a suggestion of a set of fans that I can install behind my bumper to cool the radiator? Also how should I wire them so they kick on with the other aux fan at the top of the radiator?

Thanks

 

Pardon me, but since the factory setup of the main rad mechanical fan and the single powerful electric fan seem to be enough for most people, world wide; how is it you need more cooling?

Do you have a radiator half full of dexcool sludge?

Are your rad and AC condenser full of mud and leaves?

Are you using a scanner or ultra gauge to get accurate temp readings?

My point is, if you think you don't have enough cooling , and you are running hot, extra fans may not be the answer.

If your cooling problem exists at 50 mph, it is nothing to do with fans unless they are mounted in reverse direction or belt is on wrong. If problem is when slow, eliminate the possibility of viscous clutch being bad (freewheeling when hot), and electric fan never running (blades should spin freely and not be locked up).

Now if your cooling system is in great shape, and other fans and clutches are working, good. If you want to add electric fans just use a relay to control them and place relay coil to be activated by the existing fan. Be sure to use an extra in-line fuse. The existing fan is supplied power by a black/brown wire on conector C0574 pin 4. See attached pic from RAVE manual.

But if you don't have the basics working, adding fans will cover up a problem that will get worse.

 

Savanah - we 'think' the issue might be not nough air flow to the radiator on the highway.

The following are new:
Radiator, water pump, soft spring thermostat, expanion tank pressure cap, 50:50 peak fluid, properly bled system. Front fan comes on with ac, viscous fan functions.

Around own temps are low 190's, on th highway it peaks at 218. Makes no sense. Shop is speculating it is air flow related. I am beyond frustrated at ths point. Temps verified on ultraGauge.

 

If this is the "big bumper blocks the air " theory, I don't buy that. I've got a W124 Mercedes, it has two electric fans out front with a shroud, the shroud blocks 40% of the radiator.

If fan belt on wrong would mess with air flow and water pump.

If bad coolant temp sensor could throw off the readings. Could shoot right beside it with IR thermometer (top of motor between compressor and alternator). Could compare scanner read temp before cold start to ambient; if scanner say 90 degrees and it is 74 in your garage in AM, might be an issue. Can also have crud on sensor contacts making it read off normal. The sensor resistance gets lower as it heats up, so any extra partial short or ground could make it read higher temp. Could also be crud on a connector anywhere from sensor to ECU. You can unplug ECU and sensor and read cable with meter (ohms) across and each side to frame ground.

Al this assumes shop has tested for combustion gas in coolant.

 

https://landroverforums.com/forum/di...acement-51088/

 

could be a minor headgasket or crack in the block leak that only leaks under high rpm load. Or your running super lean, pull a spark plug and see if they look white.

 

You are right, your temp readings make no since, way to high at highway speeds, but another fan is not going to fix it. You really need to find why you are so high at highway speeds and fix that instead of putting a bandid on it.

 

At idle, the air flow is 600 - 800 feet per minute speed. With electric fans on, mine reads close to 1100 feet per minute. But at 60 mph, with no fans, 5,280 feet per minute. So if overheat at highway speed, cooling system can't dump enough heat fast enough. New rad takes out scale and sludge, new water pump takes out broken vanes, new stat takes out stuck stat, so what's left? Other than cracked block, gasket, and such fun?

Any time water pump replaced chance for belt route to be wrong. Double check.

Any time work done on cooling system thermostat should be last, so little holes in it don't get plugged up with trash, these let in a metered quantity of hot coolant to make stat open, block that tiny fow and stat will open later (block hotter). Also, if not a factory stat (no matter the temp rating) - there have been reports of non-oem stats opening later (or not at all).

AC condenser fins and tranny cooler and oil cooler (if equipped) could be plugged with mud.

Fan blades could be mounted reversed. Electric fan could be wired to run backwards. Cupped sides of blades go toward block.

A paper towel should be held to the grille by air flow, not blown away.

Pix of air flow meter, sat holes close up, and attachment of plumbing routes - hoses in wrong path won't help. Stubbing off heater core won't help, if bypassing make it a closed loop.

 

I'll idle in traffic upto about 210F, the fans will bring it down to about 200-205. 215 is the hottest i've seen it and that was a 102F day in stop in go traffic for about an hour on fresh paved road lol. Highway I rarely see above 195F, 189-192 mostly. Around town about 202-206 average. had headgaskets, thermo, wp etc done maybe 9 months or so ago so that should be good. Stock radiator, unknown condition... and amsoil coolant. If I saw 220 I'd pull over and do a check!

Sealevel in NJ with summer temps about 75-85, hit 95-100 on sunny days, rarely above that.... spring fall 55-70, winter 30-35, rarely below 20, -5 windchills lowest ive seen, overnight lows 15-25.

 

Do you have a PDF of the belt routing so I can verify?

I was under the impression That the viscous fan could only be mounted 1 direction. Is That not true? Could it be backwards?

The electric fan seems to be sucking and Sorta holds a napkin to the grill.