Mark VIII fan and stock alternator?

93VertLX

Founding Member
Apr 7, 2002
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Dayton, OH
I may have a lead on a cheap Mark VIII fan. I dont have the money to upgrade the alternator right now and was wondering if it is at all possible to run this fan with the stock alternator? Thanks.
 
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I've heard the Mark 7 fan pulls 45 amps. The stock alternator has 65 amps I believe.

Plus with the underdrive pulleys it'll be terrible.

Off Topic: Did 94-95 5.0's come with 130 amp alternators? Or is it 96 and up?
 
yep, you can do it. Expect a dead battery for short trips here and there. You'll have no charge in the battery after a couple starts / stops.

Just wait one minizzle for a PA performance 3G alt. It's the 'Kiss Me''Kiss Me''Kiss Me''Kiss Me'zzz.

I recently did a dual 12 inch electric....draws 20 amps and the stock alt could NOT even keep up. I had to keep the RPM's up to 4K or else I could not start the car later.

Oh and threre is a reason the 3G alt from PA peformance is so highly recommeded. It is a fantastsic piece. My headlights have never been so bright and the volt meter never even moves when every power device is on (fan, rear defrost, head lights, fog, radio, defrost fan). PA PERFORMANCE - YOU GUYS ROCK!
 
Bes ure you know which fan your getting. The T-bird, Taurus and others look just like it (same frame and fan) but probably use different motors. I just measured my TB/Tauras fan last night on low & high speeds - 11amps and 17 amps.
 
a stock 2G alternator wont come close to keeping up with a MK8 amp draw, on startup the Mk is know to spike to 60+amps. save your pennies and get a PA perf. 130 as recommended by others. I have a pep boys(yeah yeah i know....crap)130A 3G alternator and barely keeps up with my Mk8 fan and other power consuming parts.


Scott


Scott
 
According to this Ford Muscle article http://www.fordmuscle.com/archives/2001/03/paperformance/index1.shtml , the stock 2G alternator only puts out 30 amps and 11.78 volts at idle, while the 3G they tested put out 75 amps and 13.77 volts at idle. For some idea as to the amperage of my 3.8 derivative fan I blew a 30 amp in line fuse when I was testing it on the high setting using a Flex-a-lite Variable Speed Controller set to come on with the air conditioner (which I had set to max on my way home from work as a test). For most of the winter I've been using the lower speed wire on the fan with the stock 2G amp with no problems, but summer will be a different story. I'm sure I will have to upgrade to the 3G soon myself. Even on this fan judging by the blue flame that jumps from the high speed wire when you touch it to the battery post you can tell there is some serious amperage involved. Taxing a 2G alternator with an even stronger Mark VIII fan could have far reaching and undesirable results. If money is the problem (I can relate) buy the parts in stages. I know 67coupe in here just picked up a used 3G for 60 bucks, just need to know what to look for.
 
tmoss said:
Bes ure you know which fan your getting. The T-bird, Taurus and others look just like it (same frame and fan) but probably use different motors. I just measured my TB/Tauras fan last night on low & high speeds - 11amps and 17 amps.

I get 10.8amps on low with my taurus fan, but 28amps on high, with a nearly 60 amp start-up. Yours is only pulling 6 more amps on high, that doesnt seem right to me.
 
BlackGT89 said:
According to this Ford Muscle article http://www.fordmuscle.com/archives/2001/03/paperformance/index1.shtml , the stock 2G alternator only puts out 30 amps and 11.78 volts at idle, while the 3G they tested put out 75 amps and 13.77 volts at idle.

They were testing a bad alternator. If it doestnt put out 13.5=14.5v at idle, it is no good. Thirty amps at idle is pathetic. The 2G is a 75amp alt. ususally. Mine will put out 65 amps at idle if I turn on everything, and still be at 14v. If I turn everything off but the engine, it will only put out 25amps. You will only get the amperage you are calling for, so you can make the alt look good or bad depending on what you are running.

Oh, and dont try to run that Mark VIII fan with the 2G, thats suicide for you battery and could start a fire.
 
There are other wild cards here - the radiator/a-c core/intercooler/oil-tranny cooler cores all resist air moving across them. Depending on how many fins per inch, how many rows of fins and what kind of shape they're in, two identical fans can pull different current trying to draw air across the cores.
 
jerry beach said:
I get 10.8amps on low with my taurus fan, but 28amps on high, with a nearly 60 amp start-up. Yours is only pulling 6 more amps on high, that doesnt seem right to me.

Well, could be Jerry. I used some heavy cable and a 15amp/50mv shunt (biggest I had) to measure the current. The high speed exeeds the shunt rating, but I would think the shunt curve would be close enough to linear to get closer than that. I got 58mv on high and I think 35-36mv on low.
 
tmoss said:
Well, could be Jerry. I used some heavy cable and a 15amp/50mv shunt (biggest I had) to measure the current. The high speed exeeds the shunt rating, but I would think the shunt curve would be close enough to linear to get closer than that. I got 58mv on high and I think 35-36mv on low.

Thats greek to me, I dont use shunts. I bought a clamp on inductive ac/dc ammeter from UEI for $100. Its very useful for many things, such as finding out what exactly is draining your battery! And its easy for anyone to use. I got this meter at an AC supply house for residential/commercial units.
 
A shunt is a machined brass block that is machined with a skinny section that causes a certain amount of millivolts to appear across the small section at a rated amperage. It has large connectors on the block ends and small screws in the side of the block where the small section meeets the big blocks. millivolts that appear are proportional to amperage. The shunts used to be used in metering quite a bit. Now current transformers are more widely used - but they work on AC only, except for the hall effect type that you have. Shunts used to be one of two ways to measure DC current. Older cars used a series meter but larger DC currents had to be measured with a shunt. The new Hall Effect DC current meters just measure the DC field. Their accuracy was call into question when they were new. What is the stated accuracy of your meter? 5%, 10%?
 
I won't post it on a thread - robot sam spiders snoopin in here. I notice the "PM" buttons are not here!!!!! What's up with that??????? I also tried AIM but came up with an invalid page. Man this new format on Stangnet SUCKS!
 
is this the right fan?
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