Ontopic A Thread About Butt Mustard, For Those Who Drive Automobiles
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Mr. Argumentor
I fab shitboxes and shitbox accessories.
Jehannum
Puts the "pro" in procrastination
@gee, I'm going to swap to a Delco Remy 27SI alternator (100A) into my Datsun tomorrow, and I wanted to make the kill switch safe. Right now, the alternator is setup so that the charge wire runs to the small terminal on the kill switch on a 10 gauge wire, which probably isn't safe even with the 50A unit that's on it right now.
The above is the "longacre" wiring diagram for their switch (the Moroso instructions for my kill switch just shows my unsafe-as-fuck setup), but isn't the field wire supposed to run to ignition switched power?
The SI alternator has battery, field, and sense terminals (3-wire).
The above is the "longacre" wiring diagram for their switch (the Moroso instructions for my kill switch just shows my unsafe-as-fuck setup), but isn't the field wire supposed to run to ignition switched power?
The SI alternator has battery, field, and sense terminals (3-wire).
Darth Handsome
Not Nearly as Handsome as Advertised.
Ive watched the last 4 episodes of Fantom Works. What do you think of those vee-hick-ulls?
Right. Alternator field goes to +12V switched, otherwise you'll have a parasitic drain which will kill your battery. I'm thinking that diagram is intended for a race car without an ignition switch, where you'd use the kill switch as the master switch for the car and use a pushbutton or whatever to start the thing.
For a 100A alternator, you'll want a minimum 4ga, preferably 2ga path between alternator and battery, 4ga will probably get toasty if the battery is close to dead and you're winding the car up. Also make sure the kill switch is good for 100A, I figure it is if it's rated to have a starter run through it.
Couple of options for how to wire it up:
- Cheap and easy: if it's convenient to do on the motor, daisy chain the battery and starter on the existing starter harness.
- Make work project: Do a distribution block. Battery -> kill switch -> dist block -> separate paths to alternator/starter/audio/rest of car. Buy some gold plated Stinger thing from a car audio shop or whatever and make sure water can't get in it with how it's mounted.
Jehannum
Puts the "pro" in procrastination
Jehannum
Puts the "pro" in procrastination
I've already got the "make work" project in progress, because I'm mounting a fuse block in the engine bay for the light relays and e-fan that's going in.
edit: and I forgot to put a fuse on the fuel pump, too. derp.
edit: and I forgot to put a fuse on the fuel pump, too. derp.
Jehannum
Puts the "pro" in procrastination
Fuck. I re-read the installation instructions, and the fucking alternator kill on the switch is only rated for 20A.
I'm going to just share the battery-side post of the kill switch with the alternator (each with its own 2 ga cable), and use the 12V 10 ga cable as the "sense" side of the voltage regulator. That only takes mA of current.
It keeps the alternator cable hot during a wreck even if the kill switch is hit, but it should cut power to the rest of the car, and I guess I'll have to put a fuse on it.
Finally, something electrical that @Valve1138 could really get on me for.
I'm going to just share the battery-side post of the kill switch with the alternator (each with its own 2 ga cable), and use the 12V 10 ga cable as the "sense" side of the voltage regulator. That only takes mA of current.
It keeps the alternator cable hot during a wreck even if the kill switch is hit, but it should cut power to the rest of the car, and I guess I'll have to put a fuse on it.
Finally, something electrical that @Valve1138 could really get on me for.
Just put a fusible link in the alt/battery connection. Likewise with the battery/starter connection. Works for the rest of the automotive world.
Any reason you've got a kill switch on there anyway? required for running the car on a track?
Any reason you've got a kill switch on there anyway? required for running the car on a track?
Darth Handsome
Not Nearly as Handsome as Advertised.
I suggest you get out your cables and boost er.
If that dont work get out your ball peen and tap the carb.
Mr. Argumentor
I fab shitboxes and shitbox accessories.
Dad's been trying to get his VW Van running again. The old Solex carbs were so worn that there were permanent air leaks around the throttle shafts, so he found a Weber kit to replace them. It's running well, but he keeps getting issues with fuel leak-down into the crank case when it's shutoff.
His mechanic has reset the float level twice (to my knowledge) and is supposed to be fairly knowledgeable with VW Weber swaps, so I'm wondering if there's another issue that might be going on. I seem to remember that when a fuel pump gasket went out it allowed fuel to leak into the crankcase, but Dad tells me that was a combination of issues.
Anyone have any ideas on what I can pass on to Dad for stuff to check?
@Mustard Dispenser, I know you're a VW guy, can't remember who else is an air-cooled VW guy
His mechanic has reset the float level twice (to my knowledge) and is supposed to be fairly knowledgeable with VW Weber swaps, so I'm wondering if there's another issue that might be going on. I seem to remember that when a fuel pump gasket went out it allowed fuel to leak into the crankcase, but Dad tells me that was a combination of issues.
Anyone have any ideas on what I can pass on to Dad for stuff to check?
@Mustard Dispenser, I know you're a VW guy, can't remember who else is an air-cooled VW guy
Jehannum
Puts the "pro" in procrastination
Right - battery's in the back.
Battery -> kill switch (upgrade it to something that can do 100A, or get a smaller alt) -> heavy gauge to engine compartment -> distribution block -> alt/starter/car harness. Bring the alt field wire to switched ignition. Tap off the battery with a fuse holder for your rear audio stuff.
Also make sure you've got a heavy gauge ground path from engine block to chassis and batt to chassis.
Sent from my Nexus 5 using Tapatalk
Battery -> kill switch (upgrade it to something that can do 100A, or get a smaller alt) -> heavy gauge to engine compartment -> distribution block -> alt/starter/car harness. Bring the alt field wire to switched ignition. Tap off the battery with a fuse holder for your rear audio stuff.
Also make sure you've got a heavy gauge ground path from engine block to chassis and batt to chassis.
Sent from my Nexus 5 using Tapatalk
Jehannum
Puts the "pro" in procrastination
I figured it out.
Battery -> kill switch (175A continuous, 2000A surge post) -> distribution block -> alt battery post
Battery -> kill switch (20A continuous post) -> relay signal line (triggered by ignition voltage) -> alt field wire
alt sense wire -> new fuse block constant +
new fuse block constant + -> distribution block
Jehannum
Puts the "pro" in procrastination
Jehannum
Puts the "pro" in procrastination
Perfect, first try. The car starts, the fuel pump and lights work with the new fuse block, and the car dies when I hit the kill switch.
Bunch of GM weatherpak connectors so that I wouldn't have to worry about water infiltration.
The Napa people looked at me weird when I asked for a 5/32" post connector for a 4 gauge cable.
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