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-   -   Electric fan install details wanted (https://67-72chevytrucks.com/vboard/showthread.php?t=761737)

Bandit130 04-14-2018 12:55 PM

Electric fan install details wanted
 
Going to install single electric fan. Looking for details on which wiring kit I should get to work correctly.

SBC 350 stock (HEI upgrade)
Aluminum radiator
195 degree thermostat

Unsure about a 200 on and 185 off. Unsure if I need a 30, 40 or 50 amp.

Never done this before and can use all help I can get.

TIA

notallthere 04-14-2018 04:26 PM

Re: Electric fan install details wanted
 
It depends on the amp draw of the fans themselves so you may have to look at the manufacturers specifications. I have the windstar fans on my truck and my Chevelle. I used the 40 amp ones and the only issue I have is that the truck has toasted two relays in 8 years. I carry a spare in the truck right now.

Bandit130 04-14-2018 05:32 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by notallthere (Post 8238209)
It depends on the amp draw of the fans themselves so you may have to look at the manufacturers specifications. I have the windstar fans on my truck and my Chevelle. I used the 40 amp ones and the only issue I have is that the truck has toasted two relays in 8 years. I carry a spare in the truck right now.

The specs I have found state approximately 20 amp fan. Really wanting a complete kit. Maybe something on internet that I can order. Still unsure if the 200 degree on and 185 degree off is correct with using a 195 degree thermostat.

Justins76 04-14-2018 09:00 PM

Re: Electric fan install details wanted
 
I use a Tyco 75 amp relay. No problems with my Mark VIII fan I installed.

If your t-stat is 195° and the fan switch shut off is 185°, once the fan comes on, it will never shut off. Either use a 180° t-stat or a higher temp switch.

Bandit130 04-14-2018 09:06 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Justins76 (Post 8238378)
I use a Tyco 75 amp relay. No problems with my Mark VIII fan I installed.

If your t-stat is 195° and the fan switch shut off is 185°, once the fan comes on, it will never shut off. Either use a 180° t-stat or a lower temp switch.

A lower temp switch? Can you be more specific? Lower as I can think of would be like 185 on 170 off. Is that what your are referring to?

Justins76 04-14-2018 09:10 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Bandit130 (Post 8238392)
A lower temp switch? Can you be more specific? Lower as I can think of would be like 185 on 170 off. Is that what your are referring to?

Oops, a typo. I meant to say higher temp switch. I have a 195° t-stat and a switch that's 220° on/205° off.

Bandit130 04-14-2018 09:14 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Justins76 (Post 8238401)
Oops, a typo. I meant to say higher temp switch. I have a 195° t-stat and a switch that's 220° on/205° off.

OK. I understand that. So if I keep my 195 t-stat, I can get a 220 on 205 off switch. Very good. Something like that is what I've been looking for. I am not very experienced in temp cooling fan switches. I will try to find one similar to that. Thanks.

So, should a 50 amp relay be sufficient?

Searched and not finding any for 220/205. Finding a lot of 200/185 or 185/170 and 185/165.
In need of a little more help.

Justins76 04-14-2018 10:55 PM

Re: Electric fan install details wanted
 
The accuracy of these switches live a lot to be desired. I've tried many brands, and they all seem to have poor quality control. Either dont work or the temps are wrong. I've had them bad out of the box. Another died while I was on the emissions dyno. Luckily I caught it before the gauge got to the red and turned on the a/c.

That's another thing, if you have a/c, you want the fan to kick on when the a/c is on.

One thing to consider is placement. I could not put my switch in the head since it interfered with my headers, so I put in in the t-stat housing.

Here's the switch I have, AC Delco 14043275.

Bandit130 04-15-2018 10:05 AM

Re: Electric fan install details wanted
 
I found this one at Jegs that states 200 on-185 off for a 195 thermostat. Would like opinions about this kit.

http://www.jegs.com/i/JEGS-Performan...10561/10002/-1

epfatboy 04-15-2018 10:39 AM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Bandit130 (Post 8238684)
I found this one at Jegs that states 200 on-185 off for a 195 thermostat. Would like opinions about this kit.

http://www.jegs.com/i/JEGS-Performan...10561/10002/-1


I'd get the 200 on 185 off with a 180 tstat for a typical SBC. I like the engine to build to temp than have the water pump and fan do it's job.

For a relay most fans want a 30amp unless your running a super high CFM fan or your fan is starting to sh_t the bed. It's that initial ON spike that kicks the relay.

I have used that kit on a few builds, it is fine for most setups, just make sure your fan does not need more than a 30 amp initial draw. I'd also throw a spare relay in the glove box, most of these are chiniseium and while the larger percentage are fine you don't want a $5 part stranding you in traffic!

Bandit130 04-15-2018 10:42 AM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by epfatboy (Post 8238726)
I'd get the 200 on 185 off with a 180 tstat for a typical SBC. I like the engine to build to temp than have the water pump and fan do it's job.

For a relay most fans want a 30amp unless your running a super high CFM fan or your fan is starting to sh_t the bed. It's that initial ON spike that kicks the relay.

I have used that kit on a few builds, it is fine for most setups, just make sure your fan does not need more than a 30 amp initial draw. I'd also throw a spare relay in the glove box, most of these are chiniseium and while the larger percentage are fine you don't want a $5 part stranding you in traffic!

So I should change my t-stat to 180, then use this kit?

gezn2 04-15-2018 11:45 AM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Bandit130 (Post 8238097)
Going to install single electric fan. Looking for details on which wiring kit I should get to work correctly.

SBC 350 stock (HEI upgrade)
Aluminum radiator
195 degree thermostat

Unsure about a 200 on and 185 off. Unsure if I need a 30, 40 or 50 amp.

Never done this before and can use all help I can get.

TIA

I just trawled through my bookmarks, and Photobucket getting greedy has made most of them useless for this :(
My setups are a homebrew MarkVIII and an HHR with a continuous-duty solenoid doing the heavy lifting controlled by one scrounged OEM cube relay triggered by an OEM fan switch, put another cube relay in the circuit and it would handle AC :metal:
If the weather stays crappy I'll try to get a drawing up, wiring the thing isn't all that hard.
Dave Barton over in the Volvo world posted a great PDF that was my jumping off point:
http://www.davebarton.com/pdf/coolingfandiagrams.pdf
Amp draw depends on what your fan wants, the big draws are momentary so a reasonably sized fusible link or PAL fuse on the 'hot' side is all you need.
When I was doing my research the subject of fan switch temperatures and location seemed to generate a *lot* of crosstalk :banghead: There is more than one way to do it and they all work *if* done correctly. If you *have* the 200 switch it can work fine with a 195 thermostat if you have it downstream of the thermostat in the upper rad hose or rad inlet tank, in the block or the coolant crossover and the fan will never shut off and all the benefits of e-fans evaporate :(. If you want the switch in the crossover or head you'll need a higher temp trigger, around 210, which is why I prefer the system lots of OEMs use and put a 185 degree switch in the rad outlet tank or return hose, the fans only run when the rad isn't keeping up.
I tend to stick with re-purposed OEM stuff, it gets lots of testing before it hits the streets.
More later :smoke:

gezn2 04-15-2018 12:34 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Bandit130 (Post 8238684)
I found this one at Jegs that states 200 on-185 off for a 195 thermostat. Would like opinions about this kit.

http://www.jegs.com/i/JEGS-Performan...10561/10002/-1


If you're using a fairly light-drawing fan it ought to work as long as the chineseium parts hold up :rolleyes:
If you use that knockoff Bosch cube to drive a heavier-duty contactor instead of running the fan directly it *might* last a long time.

gezn2 04-15-2018 12:52 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Bandit130 (Post 8238735)
So I should change my t-stat to 180, then use this kit?

IMO it will certainly work, but the cooler thermostat is a band-aid.
OTOH If you put that sensor downstream of the thermostat the engine will come up to the stock temperature and stay there.

Bandit130 04-15-2018 01:29 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by gezn2 (Post 8238854)
IMO it will certainly work, but the cooler thermostat is a band-aid.
OTOH If you put that sensor downstream of the thermostat the engine will come up to the stock temperature and stay there.

You mention band-aid, is this a bad thing to do?
Where downstream is a suggested place to place sensor?
Is placing sensor into top of water pump an option? There is a plug there now.

gezn2 04-15-2018 02:16 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Bandit130 (Post 8238881)
You mention band-aid, is this a bad thing to do?
Where downstream is a suggested place to place sensor?
Is placing sensor into top of water pump an option? There is a plug there now.

IMO it is a balancing act, putting the fan switch in the water jacket of the engine guarantees that your e-fan and the thermostat will be fighting each other under some conditions.
180 degrees was standard temp until the '70s, the 'band-aid' comment comes from using it as a workaround :)
A 200 degree sensor would work fine, with a 195 thermostat, in the coolant outlet after the thermostat, the upper rad hose, or the 'top' or incoming radiator tank. It will certainly work in the crossover or head you'll just be running the fan a lot more than needed.
I've seen fan switches installed in the water pump, the temps there will only be a few degrees more than the return coolant from the radiator, it should work great with a sensor that triggers about 10 degrees below your thermostat temp :metal:

tucsonjwt 04-17-2018 05:59 PM

Re: Electric fan install details wanted
 
I am not sure why you want an electric fan, but I installed a new AC Delco fan clutch on my 83 BB, then added a small electric pusher fan from a GEO Metro I got out of the junkyard (it turns on via relay when the a/c compressor turns on.) I have a factory oil cooler (it is a camper special) so I did not have room for bigger dual fans. It seems to work fine and I live in 110+ degree HotZona.

Bandit130 04-17-2018 07:06 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by tucsonjwt (Post 8240894)
I am not sure why you want an electric fan.

https://www.youtube.com/watch?v=ZXdLgaFXZzs

DieselSJ 04-17-2018 11:52 PM

Re: Electric fan install details wanted
 
An electric will never move as much air as the mechanical. Keep that in mind since you live in Texas.

Use a controller from DC Controls. They activate the fan based on the outlet temp of the radiator so it keeps the engine at a stable temperature instead of letting it cycle through 15 degrees for on/off. The fan pulls the heat out of the radiator so that is the temp you should monitor for your controller, not the engine temp. Fan should come on at the point where the radiator isn't able to keep the engine at the thermostat temp.

Honest Bob 04-18-2018 01:48 PM

Re: Electric fan install details wanted
 
I used a tarus fan and a volvo fan controller/relay. I just stuck the tarus fan into the stock 350 shroud and drilled 4 holes and bolted the two together.

https://www.cherokeeforum.com/f67/ta...ay-how-214815/

I am running the original 60 amp alt and I never got around to the temp sensor part and just have it hardwired to always run on low. I do have some sort of thermal circuit breaker wired in as a fuse. My temp gauge is broken (living dangerously) but I've been in stop and go traffic on 90 degree days for over an hour and didnt have any issues.

DieselSJ 04-19-2018 12:25 PM

Re: Electric fan install details wanted
 
Quote:

Originally Posted by Honest Bob (Post 8241538)
My temp gauge is broken (living dangerously) but I've been in stop and go traffic on 90 degree days for over an hour and didnt have any issues.

Stop and go isn't where you need the big flow.

Bandit130 04-28-2018 09:50 PM

Re: Electric fan install details wanted
 
1 Attachment(s)
UPDATE; I got a 2002 Jeep Grand Cherokee electric fan, a relay kit that is on at 200 off at 180. Picture is where temp gauge reads with or without AC. Needle may move about needle width left or right, no overheating. The gauge use to read at the first mark above cold. I am thinking this is probably a little too hot. Wondering if I replaced the 195 t-stat with a 180 or 185 would bring gauge reading down some?

SunSoaked 04-28-2018 10:03 PM

Re: Electric fan install details wanted
 
It might. But, it won't stay there if the fan isn't keeping up. That's probably the best way to test it.


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