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I did some troubleshooting today on the fans. I am still confused. Here is what I did:
Ran 14ga wire from negative battery terminal to the fan.
Ran a 14ga wire to an in-line fuse holder with a 15a fuse. From there it went to a switch rated for 60a. From there to the positive connection of the fan.
I then (with the motor and ignition off) switched on and off the fan. I had no problems. The fan turned off and no with no problems.
After that, I started the car. I switched on the fan and it came on with no sputter or stalling of the motor. I switched the fan off, and a few moments later switched it back on. The fuse blew.
I swapped the fuse with another 15a fuse and watched the fuse this time. On the first power up of the fan I could see the solder on the fuse melt but not break contact on the first switch-on. However, on the second switch-on the fuse blew again.
Why is my fan blowing a 15a fuse connected directly to the battery when the car is running but not when the engine ignition is off? I will buy another 20a fuse set on my way home tonight and put my meter in-line to see what the max amperage draw is under both conditions.
My plan going forward will be to slowly walk the ground supply and the power supply forward on the chain one link at a time to see at which point it causes the motor to stall.
WHat fans do you have? gauge sounds small for spal fans.
My SPAL fans I ran 10 gauge wires right off the alternator + terminal, 40A fuse for each fan, 50A relay for each fan. Ground goes to chassis near factory ground point under headlights, one on each side. The wires get warm running them on high. If I had 8 gauge wire I would have used that.
The reason you blew a 15A fuse with the engine running, but not when the engine is off is because the voltage was lower with it off, so less power was going through the fuse. With more voltage available, the fans were pulling more amps and that blew the fuse.
Electric motors typically pull 2-3x their normal current during startup, it's called inrush current. My spals spike around 120A each on startup. I designed and built a custom fan controller that PWM controls the fans to soft start them, and vary the % duty cycle as needed so that under normal driving, they don't pull much power and they turn on/off as soft as stock fans. But if things get hot, they can ramp up to 100% duty cycle and then move a lot of air.
The reason the motor didn't sputter with your new setup is because your wiring/fuse is limiting how much current they can pull, thus not affecting the battery voltage supplied to the coils/injectors as much as it previously did.
I upgraded all the wiring to 10ga and used a 60a switch for testing purposes. I was blowing fuses up to 25a. 30a would survive, but it would cause my motor to die immediately, which placed me back at square one.
Essentially, it is a PWM fan controller that soft starts the fans and raises the fan speeds as the radiator gets hotter. I was initially resisting this because I wanted the car to control the fans 100% of the time, but the more I thought about it, as long as the fans come on at 195 degrees (for example) and allows me to force them on (for example, when the A/C is on), I am ok with that.
I laid all the ground work yesterday so we will see how it turns out tomorrow night when I put it in.
On a separate note, I decided to start messing with my A/C. I will post more about that soon.
PWM fan controller installed. I have a couple problems with it.
First, it's intended to run off the coolant temperature of the radiator. They give you this probe you are supposed to thread through the fins of your radiator. I hated to do it, but I tried it. And it sucked. It didn't even give me discernible fan movement until about 200 degrees. Even then it was barely turning.
So instead I went with a sensor that reads the coolant temperature in the head. This results in two problems. First, the coolant in the head bares little relationship to the temperature of the coolant in the radiator during warmup, especially before the thermostat opens up. The second issue is that when the engine shuts off, the fans keep running until the ENGINE is below my set point and there is no coolant flow to move the coolant into the engine. I am worried that it will drain my battery and that I will need to install a relay.
Another issue is that at the VERY HIGHEST set point my fan starts spinning when the engine is only 155 degrees or so. This further compounds my "engine off" fan problem. I really hope I don't have to add a relay to turn the fan off. My solution will be to try and calculate a viable offset resistor that will adjust the usable range of the sensor. I want the fan to start to turn about 180-185 degrees. My ECU will then force the fan to 60% duty at 195 degrees and it will continue to rise in duty above that.
I will likely end up adding a relay either way so I can experiment with shutting off the fans at highway speed, but for now that's where I am.
I did drive it to work this morning so that was nice. It ran fairly well until I got to work and the draw on the fans caused the car to stall :(
In order to get the fan to operate at a more reasonable temperature range in it's current incarnation, I created a resistor pack wired in-line that brought the resistance of the threaded temperature probe in line with the push in probe. An off-season mod will be to add a temperature bung to the discharge side of the radiator near where the lower hose comes out and I will move the sensor there.
Also, in the time since my last post it has gone from Chicago to deals gap and back and pretty much everything has been resolved. I am still not happy with how my tune seems to change as the car gets hot but I have a few changes in mind that should eliminate some possible weak links.
The big developments: My EFR6758 has been traded for the following:
(built) Engine will be professionally assembled by a person who has done it before (all parts provided by me)
Engine will be installed in my car and broken in according to best practices
All fabrication necessary to install my sensors will be handled as part of my agreement
Ducting in the front will be upgraded from my current coro-plast stuff to something a little nicer.
Assorted other projects until the money runs out.
This means that my car will keep the precision 4828 and current manifold/downpipe for the foreseeable future. It's ok though because it will still be a monster and I don't feel like spending the money necessary to really take advantage of the 6758 anytime soon.
The motor build should be done within a week or two, and all labor should be done by the time my car comes out of storage in approximately March. It may even be in the car and broken in within a couple weeks but it's getting cold fast and I would rather keep the stock engine in the car until we get all the supporting stuff done. I am thinking honestly that maybe I should do the v8roadsters getrag rear end swap as well as the new BMW trans swap before doing the EFR turbo kit. I feel like if I am going to be upgrading to "all-of-it" I will need all the supporting mods and maybe I should just save up money to get that stuff before I worry about swapping out a perfectly good turbo setup.
Upgrades this off-season:
Upgrade fuel pump wiring with a dedicated relay. Maybe PWM?
Upgrade to return style fuel system
Upgrade to e85 compatibility
Build muffler delete for fun
Motor build details:
95'ish block with oilers deleted
10.5:1 Wiseco pistons, 84mm bore
Manley forged rods
Boundary VVT oil pump
ATI fluidamper
NB2 oil pan and windage tray/girdle
VVT head, ported with +1mm oversize valves. Exhaust valves are inconnel
ported VICS intake manifold
LS2 coils
ARP studs for everything
I am also thinking of having my spare alternator rebuilt and re-wound to give a little more amperage.
Last edited by Chiburbian; 10-29-2017 at 12:22 PM.
Started car the other day to get move some fuel through the system and give the battery some relief since I don’t have it on the charger. It’s now dripping coolant pretty steady from the area of the no. 3 cylinder on the drivers side. I’m hoping it’s just a loose coolant supply line for the turbo and not a cracked block from incorrect coolant mixture. :
Still having problems with shadow dash and my joying head unit talking to my MS Bluetooth adapter. MSdroid connected but not having much luck with shadowdash, and I was hoping to run shadowdash as my main gauge screen. If nothing else I can use usb but I can’t do that until after I get it tuned.
Also, the Joying head unit will stay powered up and only go to sleep if I go between off and accessory. However, if I try and start the car it does a full boot. I need to figure that one out.
Also on the agenda before I put the dash back together is to install an AEM rotary switch for boost levels or whatever I decide to use it for. Then, install powered USB port in armrest cubby. Last, figure out how to get launch control working.
So, I am troubleshooting a strange issue with my new Android head unit.
I can power it up with the key in the ACC position. The first time I go on to the ACC position it will take about 30 seconds to boot, but after that if I key it off I can wait days to turn the switch back on and it will instantly wake up from standby/sleep mode.
HOWEVER.
If I start the car, the head unit reboots. Another 30 seconds...
So, after doing some research it seemed that what was happening is that the BATT line to the head unit was dropping below the operating voltage (10.5v minimum) while cranking. During that period, the power coming in through the ACC line is interrupted.
So, I built this nifty thing...
The capacitor is 1000µF 35v, the diode is a common 1A 4001.
I found a nifty board called the Shmartboard that was the perfect size. Wired up it looks like this:
Works great... Prevents the voltage going to the BATT wire ever going below 12v. What it doesn't do, is prevent a reboot on my head unit... :(
Odd thing I noticed though, when not hooked up to the head unit the voltage goes to 18v. Which IS above the operating voltage of the head unit. IF that is the problem, what could be causing an over-voltage spike enough to charge up that capacitor? Is that common? Could that be the problem?
Unfortunately it's going to take a pretty decent pay cut to get me out of the state as well.
"Cost of living" is better supposedly but I still need to pay my bills and my debt isn't going to miraculously disappear. The type of property I am looking for looks like it's only available at a distance from my desired place of employment that is equal or greater in distance and commute time to where I am at now, which I am not thrilled with either.
But it means I would be living with my fiance which is the whole point. And It would get me out of this state.
Living with the beloved is worthwhile. GA is not a terrible state. GA commuting around Atlanta can be horrendous, but I've only experienced that from a distance and the occasional visit.
Bottom line if it puts you with your beloved and is otherwise a wash, it's a no brainer.
Ok. So next weekend it didn't happen as far as I understand. I was out of town in Atlanta for a job interview. Went pretty well. I am expecting an offer once I get my background screening packet complete and mailed in. Hopefully they offer a wage I can afford. I really like the idea of moving South as of right now.
The population increased without enough road widening to keep the traffic down at reasonable levels. But many southern cities have the same problem due to the exodus of talent from northern decay/taxes/weather. Which part of town?
Road Atlanta, Atlanta Motorsports Park, and Miatas at the Gap will be within easy reach. Roebling Road and Barber Motorsports Park aren't too far away, either.
Well, the job is at Emory, so when I look I will be looking somewhere around Snellville, Lithonia etc. Fiance is currently near Bethlehem/Winder. It will be a long commute until we buy a house and relocate. It will be a long commute either way honestly, but if we can get a nice property and stick to about an hour commute I will be happy.
Emory is a tough commute because it is inside the perimeter. Lithonia is way too hood for me. This is why lots of people commute a very long way to work downtown and live in quieter neighborhoods further out. Stone Mountain used to be really nice in the 1980s but it got swallowed up by hood sprawl. Where you live is typically where you will shop and go to restaurants and use local services. You want that to be someplace safe for you and your wife. Perhaps Rob @m2cupcar can shed some light since he lives in the area now.
I know Conyers up to Stone Mountain is mostly no bueno but don't know my way around the Snellville to Winder area.
Last edited by sixshooter; 03-29-2018 at 07:46 AM.
Well, I am trying not to make a move backwards in terms of commute distance (and much further backward in terms of commute time). I currently live about 35 miles from work and it takes me 45-1:30 to get to work. Lately closer to 50 minutes.
I realize that i'm not getting a shorter commute time wise at least not with what I am willing to spend.
What I DO want, is 1-4 acres, preferably a house where someone had horses, pigs etc. I want space and the freedom to put up a garage with a lift. I want to do some permaculture style landscaping and avoid big open grassy areas for the most part. (This in time of course). The buildings would be converted to workshops, plant nursery, storage, etc.
Thank you for mentioning the "where you shop, eat etc" info. That is something I didn't think about.
Winder is too far out. 45 miles each way and up to 2.5 hours commute each way. I'll do it for a time (including leaving well before I have to get to work). I don't want to do it long term.
07-29-2017, 04:28 PM
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