Fan Wiring From Scratch
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Engine: 350 crate
Transmission: THM700-R4
Fan Wiring From Scratch
I have a 1988 Camaro. Vin codes say it was a 305tpi? When I got it it had a carburetated v6 with mechanical fan. I am doing a "True" budget build so I am trying to keep the money as little as possible but since ive had several projects over the years I have plenty of spare parts laying around to trade. I replaced the V6 with a 350 crate from my totaled out Buick and ECM delete. Right now I am trying to wire the fan from scratch. Here is my wiring diagram so far..can someone tell me if i am on the right track? I am planning on using a couple of the wires I deleted to run thru the c100
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From: Fairhope, AL
Car: 89RS(other cars & pics in vBgarage)
Engine: LO3, 305 TBI Mildly Modified
Transmission: BakerBuilt 700R4 w/B&M Megashifter
Axle/Gears: 3.23 Auburn Pro Series LSD
Re: Fan Wiring From Scratch
looks right to me ...... got a switch with a thermo, i like that idea
taking the 305 tpi out for a 6
good luck with the swap to the crate engine
taking the 305 tpi out for a 6

good luck with the swap to the crate engine
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Joined: Sep 2002
Posts: 9,192
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From: Cary, North Carolina
Car: 1992 RS
Engine: Carbed 350
Transmission: 700R4
Axle/Gears: 3.42 posi
Re: Fan Wiring From Scratch
Your relay wiring diag looks wrong to me.
terminal 30 should have the constant 12v+ from the battery.
terminal 87 should be the 12v+ OUT from relay to the fan.
You want the indicator light on terminal 87 as well.
When terminal 85 and 86 make a complete circuit (ground on one, 12v+ on the other), the relay "activates", and 12v+ is transferred from term 30 to term 87 (with a SPST relay). In the case of a SPDT relay, term 87a gets the 12v+ from 30 BEFORE being "activated", then term 87 gets the 12v+ from 30 after "activation".
So, you want 12v+ to either 85 or 86, and ground (toggle or thermo switch or both) to the the other, constant battery power to 30 on a heavy gauge wire, and the fan pos connected to 87 on a heavy gauge wire.
terminal 30 should have the constant 12v+ from the battery.
terminal 87 should be the 12v+ OUT from relay to the fan.
You want the indicator light on terminal 87 as well.
When terminal 85 and 86 make a complete circuit (ground on one, 12v+ on the other), the relay "activates", and 12v+ is transferred from term 30 to term 87 (with a SPST relay). In the case of a SPDT relay, term 87a gets the 12v+ from 30 BEFORE being "activated", then term 87 gets the 12v+ from 30 after "activation".
So, you want 12v+ to either 85 or 86, and ground (toggle or thermo switch or both) to the the other, constant battery power to 30 on a heavy gauge wire, and the fan pos connected to 87 on a heavy gauge wire.
Re: Fan Wiring From Scratch
Related question:
I have an 88 firebird, and I'm wiring a fan with a toggle switch. (No therm)
Here's the setup I've been directed to use.
30 - Constant 12v from battery to Relay
85 - Hot-in-run source
86 - relay to toggle switch, toggle switch to ground
87 - relay out to fan
87a - not used
I'd like to double check that this is a correct setup, and if so, I'm really new to automotive wiring and would like to know where exactly I need to wire to for my constant 12v source and the hot-in-run source.
I have an 88 firebird, and I'm wiring a fan with a toggle switch. (No therm)
Here's the setup I've been directed to use.
30 - Constant 12v from battery to Relay
85 - Hot-in-run source
86 - relay to toggle switch, toggle switch to ground
87 - relay out to fan
87a - not used
I'd like to double check that this is a correct setup, and if so, I'm really new to automotive wiring and would like to know where exactly I need to wire to for my constant 12v source and the hot-in-run source.
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