Electric Fan Conversion

[warmonger]

A couple little caveats to throw in here. The transmission cooler in the factory radiator of most cars is weak at best. If you pull trailers or drive at slower speeds at higher rpms (low range or rock crawling) a tranny cooler is a good idea. How you hose it in makes all the difference in the world to the radiator. If you put the hose on incoming line of the radiator, it will cool the tranny fluid prior to entering the radiator, hopefully reducing the temp of the coolant slightly or cutting back on the amount of heat transferred. (Keep in mind this is hypothetical. Without an engine temp gauge and a tranny temp gauge, you couldn't verify this.) If installed on the out going side, it should have no effect on coolant temp from factory.

As for engine oil coolers, that is really a matter of personal choice. It may very well make your engine last longer. But since the oil is not a primary cooling source in the motor, the effect won't be huge. You will see no performance change with any of these mods. All you will be doing is helping the motor cool more efficiently.

As for the changes based on engine temp, that is VERY true. A lot of people don't realize what effect engine temp has on an emission controlled motor. I have seen improperly gapped spark plugs cause detonation. Also, if you live in a northern climate, you don't want to cool the motor too much for obvious reasons. But keep in mind this requires dramatic changes in engine temp, say putting in a 160 degree thermostat. Simply adding a trans cooler or oil cooler won't effect this by itself. Adding electric cooling fans and stuff can dramatically effect it though. That's why I am doing engine phase (Phase 6) last. I will let everyone else guinea pig it for me so I can learn from others mistakes and successes.

[Lance]

You Tell'm War!

[ned946]

Follow up:
I e-mailed the mag to ask them why they didn't include an oil cooler in their article. I got an e-mail back and they stated what has already been stated here!




From: quinnelc@emapUSA.com (Cole Quinnell)
To: NED946@aol.com
CC: PeweR@emapUSA.com (Rick Pewe)



We ran an oil cooler on the Jeep previously. While not part of this testing, so we don't have solid A:B:C testing data, it did not make a noticeable difference in engine coolant temperature.

An oil cooler (or power-steering cooler) will keep that fluid cooler which, of course, is better for the engine (or power steering). However, it does not work effectively to cool the engine because the bulk of the engine heat is generated in the cylinders and around the exhaust valves in the head. These areas are surrounded by cooling passages carrying engine coolant. Even if your engine oil is 20 degrees cooler, it won't effectively lower the engine coolant temperature. Also, oil is significantly less efficient in transferring heat compared to water or 50/50 coolant and water mix. Therefore, it cannot efficiently radiate heat or transfer it to the air through a radiator.

This is a smattering of information. I hope it answers your question.

Thanks,

Cole


>>> <NED946@aol.com> 9/3/01 3:41:10 PM >>>
In your October 2001 story, "Our Trials and Errors in Improving a 4X4's
Cooling System," you conclude that in your configuration, all of your
modifications netted "no real change."
Additional cooling is something that I am currently working on (I now have
a transmission cooler and a power steering cooler) and I was contemplating a
"Derale 16 Pass 10" Reversible Turbo Fan" oil cooler. Is there a reason that
option (or similar) was not considered for your Flatfender?

Ned

[warmonger]

Just an interesting little note. Did you know that the Cadillac Northstar motor is cooled primarily by the engine oil? It is designed so you can literally run the engine out of coolant but continue to drive. I for one wouldn't have the #$%& to test the theory out on a $45,000 car, but it is supposed to work. The block is cooled entirely by the oil. Only the heads flow coolant. Doesn't pertain to Xterras, but interesting nonetheless.

As for the mags conclusions on oil coolers, I agree totally. I know I will be adding a tranny cooler on my X, but the engine oil cooler will be left off. It's not something to worry about.

[Lance]

Yep.

Northstar's excepted, as a design, most people cool the oil so it stays as oil, and not to cool the engine. When the oil gets too hot, it can coke, break down (No lube...just deposits instead). As having a coke in this case is a bad thing...they want the oil to stay cool enough to avoid that.

If you use a pure synthetic (Not a blend) you avoid this altogether...they will keep working no matter how hot your engine gets.

Maybe a synthetic run Northstar in the Flattie instead of the (Mouse?/Rat?) V8 would be an improvement?

[wqbang]

Originally posted by warmonger
Just an interesting little note. Did you know that the Cadillac Northstar motor is cooled primarily by the engine oil? It is designed so you can literally run the engine out of coolant but continue to drive. I for one wouldn't have the #$%& to test the theory out on a $45,000 car, but it is supposed to work. The block is cooled entirely by the oil. Only the heads flow coolant.

I was also under the impression that when the Northstar system senses a loss of coolant the the system actualy utilizes 4 cylinders for cooling the engine with air, alternating between all 8 cylinders. I might be delusional though.

[Lance]

Despite the possibility that you are delusional, you are correct about the 4/4 oil/air split on limp home mode for the Northstar system...loose all the coolant, and the thing drops to a 4 cyl with air injection on the other 4.

I wonder what the system does if you loose all of the oil instead? Re-Route its ATF ? Have the On-Star call the EPA to clean it up?

[jnapier]

Originally posted by warmonger
Just an interesting little note. Did you know that the Cadillac Northstar motor is cooled primarily by the engine oil.

So is a Porche 911 Carrera.

My mom took hers one time (only once) to a Jiffy Lube and when they got done she asked how many quarts of oil they replaced.
--"Three. Why?"
"That's an oil-cooled engine, so it must be more than that."
--"Ma'am, cars don't need more than that."
"How many quarts did you drain?"
--"Let me check..."

Turns out they drained 16 quarts (IIRC), but the next guy only replaced 3. Needless to say my mom has since only taken it to a dealer.

[Lance]

Jiffy Rube....say no more

[ned946]

I guess I was thinking back to my 1979 Suzuki GS1000 and my Suzuki Bandit 1200S days. No coolant, just oil cooler (on the bandit) and good old air. I realize the Xterra ain't a motorcycle and it isn't designed to be an oil cooled engine, but I did think that removing heat would benefit overall (especially with a temp activated sandwich adaptor that won't allow oil to flow to the cooler unless over 180 degrees) especially at low speed, high temp trails.

[Lance]

Aircooled engines are not the best for heavy loads...they are lighter though...

[rednec]

I've been able to test the fan setup a little more over the past week. I noticed with only the one 16" fan that it would start to overheat when sitting idle with the A/C on. I installed a 10" pusher fan last night and everything seems to be good. I let my truck sit idle with the A/C on for about 30 minutes and it didn't get above the 1/2 way mark. A/C seems to blow a little cooler too. I gonna try and hit some trails in the next week or so and see how it does then.

[Lance]

Red - Suposed to get hotter this weekend too...sounds like you might be ready for it!

[rednec]

Things seem to be doing great. The temp. gauge did not move above the half way point. It's almost 90 degrees here today. I'm very happy with this mod. Seems to have a little more take off power with out the clutch fan. Gonna install a voltage gauge this evening to see if I'm pulling to much power.

[Lance]

Sounds like the fans are doing it for you....good idea on checking the draw...the fan motors are rated typically around 10 - 20 amps at full draw...less as they have momentum, etc...take the readings on start-up, as well as while running...makes a difference,