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Old 06-18-2006, 04:36 PM
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Originally Posted by rapsag
I was not correct on the fuse set up. There is a fuse on the battery side of the switch which is 25 amp. I also then found a 25 amp fuse on the output side of the switch, and it is this fuse and the switch that heats up. I assume because it is on the output side.
Fuses will not stand up to the spike issues of a motor, that open as soon as the current exceeds the rating of the draw..even a slo~blow will open up..Always use a fuse link..They MUST heat up and "Burn" for some time before they will open..a Fuse can leave you without a fan and in an overheat in traffic..

I checked the ground and found it grounded to chassis through the radiator frame (also not good?).
Good Grounding for your car:

Run a properly gauged Ground cable from the battery to any handy bolt at or near the starter, From that same bolt get a Battery cable at the parts store, that has two 3/8 ring terminals on each end and attach it there and to the Frame.

Next get some 10 gauge wire and ring terminals and run that from your bolt on the block to the Firewall, and another to the Alternator bracket or mount bolt.

Next get some Wire Braid, (Radio Shack) and install braid from the radiator support to the frame, Fenderwells to frame , hood to firewall, Doors to door posts, gas flap to body, tailgate / Trunk to body.

At each point the wire is grounded, Burnish ALL the paint and grease off to bare metal. Use a proper star-washer and lock. Use sheetmetal or Tech screws where no screws are available.

It sounds like a lot of work, but after you assemble all the parts, it's only a few hours to do..and you'll end up with a system that will work reliably for many years to come..and can eliminate that from your troubleshooting list.

Doc, thanks for the prompt reply, and I will do just as you suggest. Please explain:
"Coil power to switch now." <--This will be to the switch from the fan as it stands the relay coil.

"Coil ground to a good bonded hard ground" <---the other side of the relay coil to a known good ground/body part, burnished surface and a star-washer.

Are you referring to the Relay Coil?<---Yes

Also, I am not sure of the gauge of the original fan wires, but they don't look like 10 gauge. Will a soldered splice with 10 gauge as close as possible to the fan be OK? (I can't get to the fan itself, as it is in never, never land in front of the radiator and behind the grill).
I would cut as close to the motor as possible, install ring terminals and a 2 terminal terminal the radiator support..10 gauge out from there.

And also, the battery ground cable is bolted to the block, would that place fit your description of a 'bonded' hard ground?
Read "Good Grounding" above ....

Lastly, will I still be able to power the relay with direct twelve volts (always on) so I can use the fan to cool down after engine is shut down. Don't want to use a thermostat.
Yes, just wire it as above...Power to the relay from the switch, and hard ground to the battery or body.

Your answer will as always be appreciated, and I will be able to get busy with the above answers, (sorry for so many questions).

No problem!

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