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Mark VIII Fan Wiring Questions

  • Thread starter Thread starter ImportSlayer347
  • Start date Start date May 21, 2011
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ImportSlayer347

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Oct 13, 2008
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Sarasota, FL
May 21, 2011
#1
  • May 21, 2011
  • #1
I recently established that my 2,800 cfm electric fan is not doing a very good job at keeping the Stroker cool. I ordered a Mark VIII fan and I am planning the wiring before starting the install. My research has me conflicted. The install "How To" write ups for the Mark VIII fan I came across recommend using a 30 amp fuse and 30 amp relay. However, I also found that these fans use around 80-90 amps when starting up.

Should I use an 80 amp relay with a 100 amp circuit breaker to maintain that high current?

My other question is will my Hayden thermal control switch handle that amount of current?

This is the switch I bought...
Hayden Automotive 3653 - Hayden Electric Fan Controls - Overview - SummitRacing.com
 

ImportSlayer347

Member
Oct 13, 2008
173
1
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Sarasota, FL
May 21, 2011
#2
  • May 21, 2011
  • #2
Disregard the second question. I suppose if I put the thermal switch on the ignition side of the relay, current load shouldn't be a problem.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,934
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Massachusetts
May 21, 2011
#3
  • May 21, 2011
  • #3
They way I do my fan setup is to let any controller or switch I use activate a relay.

They have the main fan power run through a #8 wire through a 75a relay with a 60A maxi-fuse.

75a relay - Google Search
 

ImportSlayer347

Member
Oct 13, 2008
173
1
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Sarasota, FL
May 21, 2011
#4
  • May 21, 2011
  • #4
Thats the way I was thinking. I may put a circuit breaker on it instead of a maxi fuse. Thanks for the link. I couldn't remember the manufacturer. I wish there was a place locally that sold them. Hate having to wait for shipping.
 

ImportSlayer347

Member
Oct 13, 2008
173
1
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Sarasota, FL
May 21, 2011
#5
  • May 21, 2011
  • #5
Napa has them for $53. I guess I will wait for shipping.
 
S

steelie4u

Member
Jun 27, 2009
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May 22, 2011
#6
  • May 22, 2011
  • #6
I u se a DCC controller and it works awesome, its all adjustable and very accurate my car never gets above 195 even on the hottest days
 

ImportSlayer347

Member
Oct 13, 2008
173
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19
Sarasota, FL
May 22, 2011
#7
  • May 22, 2011
  • #7
Where can I find one of these DCC controllers?
 

HISSIN50

"How long does it take to get help in here?
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May 22, 2011
#8
  • May 22, 2011
  • #8
Welcome to Delta Current Control
 

ImportSlayer347

Member
Oct 13, 2008
173
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Sarasota, FL
May 26, 2011
#9
  • May 26, 2011
  • #9
My fan arrived this week and I checked the part number. It is from a '94 Thunderbird. I really wish the people on Ebay selling fans wouldn't advertise them as Mark VIII fans if that isn't what they are. They look identical but I am hearing these don't spin as fast as the MK8 fans. I'm gonna try it and see if it is sufficient. Crap.
 
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bgoins

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May 26, 2011
#10
  • May 26, 2011
  • #10
That does suck. Seems like the people who have the DCC controlers like them but they are $ and I've heard they take a while to get because they are made to order
 

ImportSlayer347

Member
Oct 13, 2008
173
1
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Sarasota, FL
May 26, 2011
#11
  • May 26, 2011
  • #11
Well apparently this thunderbird fan is single speed. I'm just gonna wire it up with a 75 amp relay, 100 amp circuit breaker, and I'll put the thermal switch on the ignition side of the relay. I'll set the fan to come on at 180 which will match my thermostat. I'm just hoping this solves the problem. I'm tired of messing around with this.
 

ImportSlayer347

Member
Oct 13, 2008
173
1
19
Sarasota, FL
May 26, 2011
#12
  • May 26, 2011
  • #12
Good News:
I got the fan installed with some shroud trimming. I also had to move the radiator about 1/4". All wired up nice and neat. It was holding at a steady 190 at idle.

Bad News:
I noticed a leak somewhere dripping off the bottom of the radiator. I can't win. FML.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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May 26, 2011
#13
  • May 26, 2011
  • #13
ImportSlayer347 said:
Well apparently this thunderbird fan is single speed. I'm just gonna wire it up with a 75 amp relay, 100 amp circuit breaker, and I'll put the thermal switch on the ignition side of the relay. I'll set the fan to come on at 180 which will match my thermostat. I'm just hoping this solves the problem. I'm tired of messing around with this.
Click to expand...

You'll want the fan settings phased above that of the t-stat's fully open temp. If your stat is fully open at 180* (assuming you have a balanced t-stat), you could use 200/190 on/off.
 
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steelie4u

Member
Jun 27, 2009
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May 26, 2011
#14
  • May 26, 2011
  • #14
HISSIN50 said:
You'll want the fan settings phased above that of the t-stat's fully open temp. If your stat is fully open at 180* (assuming you have a balanced t-stat), you could use 200/190 on/off.
Click to expand...


thats how i set mine
 

ImportSlayer347

Member
Oct 13, 2008
173
1
19
Sarasota, FL
May 28, 2011
#15
  • May 28, 2011
  • #15
Everything with the fan is good, but the damn radiator is leaking where I put one of the radiator ties through. Tiny leak somewhere between the fins. I don't know what to do now. Probably try some Bar's Leak.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
May 28, 2011
#16
  • May 28, 2011
  • #16
You know what to do. Mount the fan using brackets (not pull-throughs) and have a shop fix the rad (if the rad is older, weigh the cost of repair vs a fresh rad).
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
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May 28, 2011
#17
  • May 28, 2011
  • #17
I regret using pull throughs now. I almost would rather have left the stock fan clutch on.
 

ratio411

Founding Member
Apr 21, 2002
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Pensacola FL
May 29, 2011
#18
  • May 29, 2011
  • #18
ImportSlayer347 said:
Disregard the second question. I suppose if I put the thermal switch on the ignition side of the relay, current load shouldn't be a problem.
Click to expand...

True.

We are about to do an SN-95 fan (~60 amps from what I am told), and we'll be using that same adjustable controller.

Now to read the rest of the thread and get ideas!
 

ratio411

Founding Member
Apr 21, 2002
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May 29, 2011
#19
  • May 29, 2011
  • #19
Yeah, I thought about pull-throughs, but quickly ruled them out.
The worst part about retrofitting stock parts is they are not very user friendly when it comes to custom mounting.
 

ImportSlayer347

Member
Oct 13, 2008
173
1
19
Sarasota, FL
May 30, 2011
#20
  • May 30, 2011
  • #20
Well after emoving the fan, I found the leak. It was NOT where I put the pull-through straps. It is a tiny nick where I think I nicked it with a drill bit by accident. It is a tiny pinhole. I am thinking I will just clean the hell out of it and use some JB Weld or some kind of aluminum epoxy. It is very easy to get to without removing the radiator.

Any ideas as to what I should use? I was also considering soldering it.

Side note: Mounting with pull-through straps worked just fine. It stayed in place nicely and looked very clean. I put a thin layer of foam padding in between the shroud and the radiator. Sealed it airtight.
 
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