hey guys. i have a few questions and problems on my f4i.
I purchased this used and it had a busted radiator. i replaced with a new radiator and i seem to be having shorts when the radiator moves. it shorts at the upper mounting point to the frame when i move it too much. i believe its the fan harness that's causing the short.

the fan harness is on a direct connection to the battery. power and ground. the fan comes on normally at 230 degrees no problem. there is a ground wire at the switch as well and it is grounded. i dont know if aluminum can be grounded though

pictures always work better
here is how its mounted


this eyelet is where it see it shorting


what do you guys think can be causing this? the harness is grounded to battery so why would it be shorting at the eyelet? i disconnected the plug and it seems to not do it
thanks

 

Look downrange at the thermostat.
It's the black and silver thing, going into the radiator below the hose.
In the first picture. This is essentially a thermal controled switch.

The positive, from the battery, goes to it. When the temp is high enough,
it closes a contact, sending the current to the fan.
Which is then grounded to the frame, to complete the circuit.

Check all of the connections and wires through that area.
You probably have a short bypassing the thermostat/fan.

That's my best guess.
Hope it helps, ern

 

that did help quite a bit. although a little late. i took it for a ride around the block and i saw a huge cloud of smoke coming from under me. looked down and didnt know what it was. pulled over and saw the "harness" i made completely melted.
so the + goes the the spade terminal on the thermostat and the - goes to the ground wire on the radiator? the PO might have hacked the original harness so i don't know how it's supposed to look. its just 2 individual wires running straight to the battery so i just wrapped it in electrical tape to make a "harness"

how is it grounded to frame at all? the radiator attaches to the frame by rubber grommets so i'm not sure how it would work.

 

There is supposed to be a ground strap that goes from the radiator to the frame.

How many terminals are on your switch?

 

the thermostat switch? only one

 

The switch completes the ground through the threads on the radiator. The radiator need to be grounded to the frame because its rubber mounted.

I will look at the diagram tomorrow. But iirc, the power goes to the fan, the fan ground goes to the switch, and the tab on the radiator or the fan bolt has a wire that goes to the frame or radiator mount bolt (which touches the frame)

 

i found out what was the problem. dumb me.
i had to take the connectors inside the plug apart so i could splice new wire into it. i guess i left + and - on opposite ends so it was shorting out. good thing when the wires melted, it didnt melt any other harnesses next to it.

 

the ground is carried down to the assembly via the wiring harnes.. the plastic connector. common issue with 90% of engine electrical systems is lack of grounding. i piggy backed a ground wire from the neg on the battery up the wiring harness and spliced it in to the ground line and added a ground to the radiator. stopped delayed fan headlights are brighter also. have experienced even better electrical system performance.

on a side note i added a fan switch toggle turn the fan on manually on really hot days and can keep the engine running at 185 degrees. i let the fan auto cycle on cooler days.

this is just me not saying you should do it take it how you take it if you do decide to do it read your wiring diagram very careful.

 

Cool man. Where do you mount the switch at. I want to do a switch as well. Do you use a relay to it?