I use Amsoil ATF. It will add a little over a quart, 33oz to be exact. Plus the added cooler lines.
CK5
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'89 R3500 Crew Cab 2wd to 4wd conversion & beyond
- Thread starter mrk5
- Start date
Started out with 2wd TBI350 with SM465 to current 4wd with 454, 700r4, NP241
I'm having relay trouble getting the trans cooler wired up.
The relay will be triggered by the Terminator thru the ground side. This means the ground wire is quite long to get from the bed to the Terminator in the dash.
The power side of the relay I connected to the battery along with the main power feed. Since the Terminator will only be on with the ignition figured it made wiring easier.
Aside from the ground to trigger the relay, all of the other wiring is less than 12" long because the bed mounted battery is right there.
There is a simple wiring diagram below.
The problem came when I test wired it. I just put the relay trigger ground with the long wire straight to the battery negative. The wire got smoking hot quickly.
I double checked the wiring and I had the positive and ground trigger wires backwards on the relay.
I fixed the wires and the exact same thing happened, ground trigger wire smoking hot immediately.
Did I ruin the relay with the trigger wires swapped? Is the 20ga ground trigger too small gauge? Is the ground trigger too long? Or do I have a bad relay? Is the problem having the trigger power and main power connected at the same place?
FWIW, the fan works fine if I jumper the battery supply wire to the fan.
The relay will be triggered by the Terminator thru the ground side. This means the ground wire is quite long to get from the bed to the Terminator in the dash.
The power side of the relay I connected to the battery along with the main power feed. Since the Terminator will only be on with the ignition figured it made wiring easier.
Aside from the ground to trigger the relay, all of the other wiring is less than 12" long because the bed mounted battery is right there.
There is a simple wiring diagram below.
The problem came when I test wired it. I just put the relay trigger ground with the long wire straight to the battery negative. The wire got smoking hot quickly.
I double checked the wiring and I had the positive and ground trigger wires backwards on the relay.
I fixed the wires and the exact same thing happened, ground trigger wire smoking hot immediately.
Did I ruin the relay with the trigger wires swapped? Is the 20ga ground trigger too small gauge? Is the ground trigger too long? Or do I have a bad relay? Is the problem having the trigger power and main power connected at the same place?
FWIW, the fan works fine if I jumper the battery supply wire to the fan.
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85 and 86 don't matter on the coil side. The other 2 are just power in and out 87 and 30. They don't really matter either. Something isn't right if your ground got hot.
I would bench test the relay with an Ohm meter. Make sure that there isn't something screwed up internally. Even new parts can be a problem, right?
I didn't think 85 and 86 mattered either but the instructions do specifically say that one of them must be positive and the other negative, I don't remember which tho.
I was thinking a little bench testing might be in order.
I was just looking at that cooler a couple weeks ago. What size fluid lines are you running? Are you looping the radiator cooler first?
Some relays have a diode in them to prevent reverse voltage spikes, on those particular units the polarity matters on 85 and 86. It will usually show this on the relay diagram. Because of this I typically wire all my relays in case I put one in, and you should use either a resistor or diode relay to protect the ECU when triggered by an ECU.
And although I wouldn't think it would fry it with only 12 V, anything is possible, I've fried one before, but it just didn't work, it never made the wire hot. It appears you have a short in the relay coil based on your test. I would try a different relay and also jumper/bypass the relay/fan terminals as a quick test to make sure the fans are working correctly.
Are you sure those eBay fans are genuine? They aren't speedmaster with Derale on them are they?
Haha! No I did test the fans and they work. If it's a knock off, they did a really good job so hopefully it cools just as well.Some relays have a diode in them to prevent reverse voltage spikes, on those particular units the polarity matters on 85 and 86. It will usually show this on the relay diagram. Because of this I typically wire all my relays in case I put one in, and you should use either a resistor or diode relay to protect the ECU when triggered by an ECU.
And although I wouldn't think it would fry it with only 12 V, anything is possible, I've fried one before, but it just didn't work, it never made the wire hot. It appears you have a short in the relay coil based on your test. I would try a different relay and also jumper/bypass the relay/fan terminals as a quick test to make sure the fans are working correctly.
Are you sure those eBay fans are genuine? They aren't speedmaster with Derale on them are they?
I'm going to try a couple more tests but I did go a head and order another relay. I've got the same relay in a couple places so even if I don't need the new one, it can be a spare backup unit.
FWIW, I'm using a Painless relay 80129
My complaint is the terminals are not labeled on the relay itself because the terminals are potted. They do include a little picture of the bottom of the relay with the terminals labeled. The trick is the picture is from the perspective of looking at the bottom of the relay. So if you're like me and already have the relay installed, you have to hold the little diagram the right way so you get the terminals right.
I'm just going to run 6an lines. The only adapters I found for the cooler are made by Derale. IIRC the cooler is 7/8-14 oring. I think you can get 10an and I know there are also barb options too.
I'm not running to the radiator, at least not for now. I frankly don't want to spend the money on the amount of hose I'll need to make that run with my long-ass truck. It'll be interesting to see what the trans temps are in the winter. Since the cooler is mounted below the spare tire it's not going to get any passive air flow. So I tend to think it may not have any issue warming up, but I could be wrong.
Okay, it's definitely a bad relay. I tested it in the truck one more time with a shorter 18ga wire and it heated up immediately again.
I pulled it out and set up 2 short pieces of wire to test it on an uninstalled battery. As soon as I touched the positive battery terminal the wire welded itself to the terminal. I panicked for half a second then jerked the wire off which took a good tug to pop off. The ground was hot as shit again.
I pulled it out and set up 2 short pieces of wire to test it on an uninstalled battery. As soon as I touched the positive battery terminal the wire welded itself to the terminal. I panicked for half a second then jerked the wire off which took a good tug to pop off. The ground was hot as shit again.
That relay does have a diode in it so 85 and 86 have to go the correct way. You sure there's not little numbers up in by the terminals? Most every one I've seen has them. Pin 30 is always the sideways one for reference.
Yep, this means diode....(in the red circle), it even says ignition protected on the top.
Not that these aging eyes can see.
This is the little diagram in the packaging for reference.
Every time I wire a relay I confuse myself and have to relearn how it works. It doesn’t help the sockets I have all are different colors. 
Every single time I do a relay I have to look up the pins. One of those mental mind block things I guess.
Since I was having trouble, I've probably looked at the little drawing a dozen times. I'm tempted to make a label that goes around the bottom to mark the terminal numbers.
Just remember 85 is less than 86.
Negative is less than positive.
Negative is less than positive.
Or in Vice Grip Garage terminology, I'm always happy with more and sad with less.
Let me know if my thinking is sound. It occurred to me with the trans cooler having over a quart in it, it could be an issue if it drains back to the trans. So I looped the lines up so the peak is above the cooler. That should keep the cooler from draining back to the trans when it's not running.
In theory it sounds right, they make one way valves for an lines if you really want to add them.
I find it takes about a week of not being started before it becomes an issue and the transmission starts leaking from anywhere it can find.
