Electric fan fuel savings?

[tom slick]

Originally Posted By: sprintman
Faster warm up with electric fans so less wear.


could offset by the small amount of load helping to warm the engine. coolant isn't flowing until the engine is warm, initial radiator temp makes little difference in the warm up cycle.
IMHO electric fans were added to vehicles for engineering reasons, not performance or efficiency reasons. a small electric fan can fit into areas that a mechanical fan can't. it also allows the use of multiple fans so cooling can be staged and the A/C system can have its own fan to make it function with cheaper/smaller parts.

the bottom line is that a properly working fan clutch adds very little load to the engine and mostly operates when at idle or when the engine is under load, during both situations the mpg gain is not really a concern.

 

[sprintman]

Australian company Davies Craig have an electric water pump which is going to be OEM'd to many automakers around the world. Now that will certainly reduce startup wear and improve economy. I will probably fit one to our Outback

http://www.daviescraig.com.au/main/display.asp?pid=26

 

[XS650]

Originally Posted By: sprintman
Australian company Davies Craig have an electric water pump which is going to be OEM'd to many automakers around the world. Now that will certainly reduce startup wear and improve economy. I will probably fit one to our Outback

http://www.daviescraig.com.au/main/display.asp?pid=26


Meziere has been producing electric after market water pumps in the US for years.

 

[moribundman]

Pierburg has also been making electric water pumps for automotive applications for years.

 

[sprintman]

So has Davies Craig, not a new product

 

[swalve]

Well, you lose efficiency because the fixed fan spins all the time, where an electric one doesn't. On the other hand, the engine is less efficient at making electricity.

The MOST efficient way would be to find some way to use the waste heat to power the cooling fan, but that gets into exotic systems...

 

[nstoolman1]

I just finished installing one on my 2003 s-10 2.2 5 speed. I used the Taurus 3.8 2-speed fan. Got it at the wrecking yard for 29.00. Paid the warranty of 10.00. Made an in the-hose-fitting for the thermostic fan switch. A couple of relays and some wire. I am still deciding if I want to use the a/c clutch to fire the high fan or use the high head pressure switch. The jury is out on any savings yet. The little 2.2 takes awhile to warm up. I drive 11 miles to work. By the time I get there the fan has yet to come on. Remember, under normal circumstances the fan will only come on if the fan switch calls for it. At speeds above 45 MPH chances are the radiator will be kept cool enough. If you run tha A/C though you might need the high speed fan. You will need a fan to come on if you run tha A/C at an idle or at stop lights. Hope this helps.

 

[meep]

Hey thanks. Let us know how the mpg's behave, I'd be great to have real info. I'd use the a/c clutch in your case. In mine, a/c is kaput and will likely stay that way, so it's not an issue. $29? good find. I've seen salvage yards ask $90...

Mike

 

[VaderSS]

I really don't see how an electric fan could help on the highway. At those speeds, the fan is just freewheeling, not using any energy.

I could see it helping in stop and go, where an engine driven fan winds up using a lot more power, while you are accelerating. The underhood area heats up, causing the fan clutch to spin the fan harder, and then when you go to take off, you wind up using more power.

The LT1 Caprice/Roadmaster/Fleetwood had an optional 5,000Lb(7,000 for Fleetwood) towing package that included an engine driven fan. That engine driven fan reduced the ratings of the engine by 10HP and 15 Lb-ft or from 260hp/330tq to 250hp/315tq. Engines and PCMs were identical.

 

[mpvue]

I'll be doing a conversion on my '96 MPV in the spring. the fan in these is really big and loud, and, as far as I can tell, it's fixed, not clutched, but I could be wrong. it just makes sense that an electric will be less drag, one less thing for the engine to turn. reports from mpvclub.com are positive. the taurus fan is popular there too, but I don't have the schedule/time to start hunting around junkyards.

 

[ikeepmychevytoo]

.

 

[nstoolman1]

Originally Posted By: VaderSS
I really don't see how an electric fan could help on the highway. At those speeds, the fan is just freewheeling, not using any energy.


The fact that the e-fan is freewheeling and not requiring energy to turn for cooling means the engine doesn't have to. Granted without an instrument to get a precise amount I would have to rely on MPG/used over a time. Anytime you free up torque used on an accessory it means the vehicle can get to running speed, where fuel use can be more efficient, quicker. If you use this new found torque for jackrabbit starts and hotrodding, then no you won't see an increase in MPG. For $60.00 it frees up some engine compartment space. I'm thinking of getting rid of the nasty twist of an air intake pipe and putting a less restrictive one. I will use the original air box. Hope I made it more clearly for everyone. Sorry about the long post.

 

[VaderSS]

mpvue, you have a fan clutch, unless someone has converted it to non-clutched, which would be very odd. Clutches do lock up though. If you cannot easily turn the fan when the engine is off, then it is locked up and needs replacing.

My point on the highway fuel economy is that the clutch will be completely unlocked at any speed over 40 or so, drawing no power from the engine.

 

[SHOZ]

Some Lincolns have electrically controlled hydraulic fans.

 

[Gary Allan]

Quote:
My point on the highway fuel economy is that the clutch will be completely unlocked at any speed over 40 or so, drawing no power from the engine.


This may be true in the winter ...but I dunno about this in the hotter weather. It will always draw less than a direct blade ..but can we assume that it cannot engage if you're driving @ 75 mph in 95F weather??

My Peugeot had the best setup. The belt driven fan was electrically clutched like an AC compressor. It also had an electric in front of the rad.

 

[gomes512]

Originally Posted By: Gary Allan

My Peugeot had the best setup. The belt driven fan was electrically clutched like an AC compressor. It also had an electric in front of the rad.



Hmmmm that is a good setup. Thought I posted in this topic already. Anyways, my buddy and I did the e-fan swap on his 4.0 grand last spring. Real PITA as there was no room in front and the Ford fan doesn't fit.

He wanted the e-fan primarily for the fact that he encounters deep water in the summer a lot (that would explain the carpetless interior). Well we finally got a nice e-fan to drop in, somewhere along 2000 cfm's as I recall. No noticeable gain in mpg on that truck. Although being able to cut that fan off in a water crossing is nice.

We did encounter a problem when the temps went north of 90 in the summer though. Stop and go traffic when using a/c or towing even a light load... forget it. Coolant temps would start to tilt to the right. The first time this happened we blew the bottom rad hose (although I think it was bad anyways).

Good luck!