Power Drop

[coupecustom]

I've recently got my Typhoon up and running again, and have my first big issue that is preventing me from driving it.

Durring the redo process of my truck I upgraded the electric fans to the syty performance one. I bought it used and it seems to be working flawlessly. I also moved the battery to the back, because there was no room up front. I also installed a new battery. Last week when I ran the truck and took it for the first drive in months I noticed that the power was dropping electrically. It was raining out and so the window wipers were just getting slower and slower.

The next day I tested the electrical system and found that at the alternator the voltage continued to drop. While running it went from 10.6 to 10.58 to 10.55 ect. So, I figured hey, the alternator must be bad or not have enough power, now that the fans were hooked up. So, I bought a new alternator....a powermaster 140 amp.

Installed the new alternator and charged up the battery, since it was a little low from before. Started the truck and I can still see the volts just drop from the alternator using my volt meter. It started out at 13.9 and over the course of five minutes dropped all the way to 12.3 volts. I felt the alternator, seemed hot, not sure if it should be hot or not, but it was warm.

The relay system for the fans that I used is from the hollisterroad company.
http://www.hollisterroad.com/proddetail.asp?prod=D4060GPT10MTFK
It specifically says to not lengthen the power wire, but obviously with my battery in the back this was not an option. Could that be the issue? I wouldn't really think that a lengthened wire would have that much of an effect but :dunno:

So need some suggestions here.
I've tested with just the key on, and theres no drop...well there is, but it takes a long time to even drop .01 of a volt.
Wiring for the relocated battery is as follows:
Positive to starter
Negative to chassis
Alternator to starter and to power block
Power block to fan relay
chassis to engine
chassis to core support
fan negative to core support

Thanks for any suggestions.

 

[coupecustom]

Re: Power Drop

I should add that I tested pulling the fuse on the fans, but the truck seemed to start hunting for idle, so the voltage was a bit all over the place. Basically, I couldn't tell if it was dropping or not. Plus the truck was already warm so I didn't want to run it too long without the fans. Maybe I'll test again in the morning when the Ty is cold.

 

[dgoodhue]

Re: Power Drop

How do you ground your battery? What did you do with your OEM battery cable?

 

[coupecustom]

Re: Power Drop

How do you ground your battery? What did you do with your OEM battery cable?

Negative battery terminal is grounded directly to the chassis/frame. Its about a 1 and 1/2 length cable that goes through the rear floor to the frame.

The OEM cable used to go directly from the battery to the rear of the engine. I used that same wire and ran it from the back of the engine down to the frame as well.

 

[ajt86]

Re: Power Drop

Check the voltage coming out of the alternator... positive lead of your multimeter to the battery cable on the alternotor... ground to ground... if its not around 14.7 the alternator is just not charging

 

[dgoodhue]

Re: Power Drop

Negative battery terminal is grounded directly to the chassis/frame. Its about a 1 and 1/2 length cable that goes through the rear floor to the frame.

The OEM cable used to go directly from the battery to the rear of the engine. I used that same wire and ran it from the back of the engine down to the frame as well.

That sounds fine to me.

 

[coupecustom]

Re: Power Drop

Did a little more testing today.
I disconnected all power wires from the alt and connected the battery lead and accessory power leads together, so that the truck could run completely off the battery. I did this because I wanted to see if there was a quick drop in voltage at the battery with the truck running. There was a drop, but really not as quick as I would think. About .1 volt every minute or two....not much for load, just the fans, engine, and intercooler pump. Didn't turn lights on or anything like that.

I then tested the positive lead on the alt with those same wires disconnected. Out of the alt I was only getting a little over 1 volt. But then I realized, alternators don't really read like that, they need load, so that wasn't a valid test.

I connected everything back up to the alternator, and reconnected the battery cables (I remove them after every test so that disconnecting/reconnecting has no chance of shock). Now, I ran the truck, and rev'ed it to about 2500 RPM, with lights on, HVAC fan blowing, stereo on. I can now see the alt kicking out 13.2 V of juice. Not near what I was hoping for, but none the less a result to me that seems the brand new alternator is working. As soon as I let off the gas, power quickly drops to somewhere around 12.2 V

I still obviously have a problem though. Even at idle, I'd like to see the voltage going up, not down. So thoughts are, with the battery relocate, I'm possibly not running enough wire or something similar for battery charge. And possibly running a ground for the alternator would help too?

Right now, the power lead that is on the back of the alternator that used to run directly to the battery, in its factory location, is now connected to the positive terminal on the starter. This same connection is where the positive lead for the battery is at. When relocating the battery to the rear is this setup ok?

 

[Black Knight]

Re: Power Drop

Right now, the power lead that is on the back of the alternator that used to run directly to the battery, in its factory location, is now connected to the positive terminal on the starter. This same connection is where the positive lead for the battery is at. When relocating the battery to the rear is this setup ok?

That's how I always do it.

 

[coupecustom]

Re: Power Drop

Little update. I looked up on powermasters website to see if they had advise on the voltage drop, with the battery located in the back. One thing they said is that it would happen if the wire from the alternator to the starter was not large enough. So, this weekend I went ahead and ran a 4 gauge wire from the alt to the starter. It was a pain, but I got it done.

NO CHANGE. Same freaking issue I can litterally just watch my volt meter record the voltage drop at the alternator and the battery. It gets low enough, that on high speed the window wippers will barely move. The voltage drops fast enough that after about 10 minutes of running the vehicle the battery will need to be charged to get it back to full capacity again.

I can see that the alternator is working but there is short or something somewhere that is stronger than the alternator. The reason I know that alt is working is because I can check voltage at the battery and it will read 13.2 then start the truck up and can see it reads 14.7. The thing is if I leave the truck running for a few minutes I can see the voltage reading 11.9 and continuing to drop.

How do I go about finding a short or whatever this is?

 

[It's just a six]

Re: Power Drop

Just wondering if you are running stock sized crank & alternator pulleys?

 

[coupecustom]

Re: Power Drop

Yep stock crank and alt pulley.

I can rev the engine and get to voltage to come up a little.....but even rev'ed I can still see the voltage drop on my volt meter.

 

[coupecustom]

Re: Power Drop

Okay made some progress, but I need a little help from my friends.

I believe that there is a short that is causing the power drop. Furthermore, it looks like it is associated with the horn wire that is connected to the keyless entry system. What I did, was disconnect the power wire to the security system and it was still active! So, then I went ahead and disconnected the acc wire for keyless entry...still active. After all this was disconnected I kept hearing a little tick from the horn, it wasn't honking, but just like a relay was kicking it or something. So I disconnected the wire that goes to the keyless entry system from the horn. Vola, security system affectively powered down. Of course now I'm like how in the world did that happen.

Tested the voltage comming from the factory horn wire in the truck and it reads 12V. Very strange. Cause I believe this should be a neg. Then I did a little darring test. I hooked up a test wire to the factory horn wire and touched it to ground...even though I knew 12V was comming from it. Welp, the horn went off. This tells me that at least the keyless entry system is working, its just getting back feed power through the horn wire, when it should not be.

So how do I fix this horn wire?

On top of that I have another issue. The ACC for the truck is also not working. If I turn the key just one click the radio does not come on as expected. So I tested this wire with volt meter as well....and yep, no power when the key is turned to ACC. Checked the fuse, its good. Now what?

 

[gstacky]

Re: Power Drop

On our trucks the accessory position is turned back, not one click ahead, one click ahead releases the column lock, 2 clicks is ignition power, 3 is start.

Your horn wire will have 12 volts when the horn button is pushed, grounds to the core support, do you have an alarm in the truck?

Edit: I may have mis-read your post, where are you testing the horn power?

 

[coupecustom]

Re: Power Drop

Update: I think I found my short.

Today I went ahead and setup my multimeter by first disconnecting the negative battery cable from the neg post on the battery. Then put the com lead of the multimeter on the neg battery post and the Volt lead (+) to the negative battery cable. This should read zero in this test. Mine read 12.78 volts.

With the multimeter hooked up I started pulling the fuses, thinking that would help me find the source. I pulled ALL the fuses, still 12+ V at the multimeter. Pulling all fuses told me that the short was before the fuse block. I then disconnected various connections in the engine compartment ... none of them brought the multimeter to zero. I then said ok, I'll pull the lead on the back of the alt. Reading dropped to about 10.8 on the multimeter.

This means the short is somewhere along the line from the power cable to the starter to the alternator. If the short was after the alternator or at the alternator, I'd see multimeter drop to zero, quick. It reads a little lower, because I've just taken some of the juice away since my alternator is grounded too. Just to be frank, a short means power is running to your ground.

Now here's my thought. The starter has the solenoid on top of it, and it is now hooked up with much larger power leads than it had from the factory, due to my battery in the back and the 4g wire to the alternator. Because of the increase in size, I believe that the power wire is hitting the engine block just enough. Since the engine is also grounded to the frame, this is causing the short, is my thoughts.

I've installed the starter a couple of times now and each time I've thought, man that’s a tight fit between the headers and engine block. I'm thinking the resolution will be to either get a smaller starter or get a ford style starter solenoid so that only one wire is going back there. I'd still need to protect it as much as possible.

Edit: I may have mis-read your post, where are you testing the horn power?

I'm testing the horn from the black wire that is lead down from the button to the harness that is on the column. From my understanding the horn button, when pressed, completes the ground circuit.

 

[coupecustom]

Re: Power Drop

On our trucks the accessory position is turned back, not one click ahead, one click ahead releases the column lock, 2 clicks is ignition power, 3 is start.

I feel like an idiot on this. Thank you for pointing this out to me.

 

[sly dvl]

Re: Power Drop

Update: I think I found my short.

Today I went ahead and setup my multimeter by first disconnecting the negative battery cable from the neg post on the battery. Then put the com lead of the multimeter on the neg battery post and the Volt lead (+) to the negative battery cable. This should read zero in this test. Mine read 12.78 volts.

Um, not quite right. Your meter is reading voltage, which is pressure. You'll have zero pressure on the ground post of the battery, but battery voltage/pressure on the negative cable going to the battery, since all the little electrons are trying to get from the pos to the neg. post on the battery.
So, in short, I don't see a problem there. Your 12.? volt reading from neg to neg is correct.

 

[coupecustom]

Re: Power Drop

Um, not quite right. Your meter is reading voltage, which is pressure. You'll have zero pressure on the ground post of the battery, but battery voltage/pressure on the negative cable going to the battery, since all the little electrons are trying to get from the pos to the neg. post on the battery.
So, in short, I don't see a problem there. Your 12.? volt reading from neg to neg is correct.

Your right, I was messuring voltage when I should have been measuring amps, for that test. It does appear very low in amperage .05. So not too concerned.

 

[coupecustom]

Re: Power Drop

So far this weekend, I did move the starter power/alt wire. They were actually touching the headers. I was able to just rotate it a bit so that its away from the header and engine. Dont know if that was a problem at all but certainly would melt through the protectant over time. It could have been a contributor to the power drop seen when the truck is running, but I'm not sure.

I did find out that the issue with the security system was that it was definately not grounded well. Once grounded, I wasn't experiencing any of the crazy issues with the horn and what not any more.

So, all in all truck seems to be doing okay. Running at about 13.5 V from the alternator when running, I wish it were higher. But I think its time to move on and see if it becomes more of an issue later. I haven't had time to test just leaving it run for an hour and see where the voltage is, but I will later. Right now seems to hold enough power for me to drive it to an A/C shop where I'll be able to have some custom lines made so that the A/C can go back in.

 

[tunerpike]

Re: Power Drop

The relay system for the fans that I used is from the hollisterroad company.
http://www.hollisterroad.com/proddetail.asp?prod=D4060GPT10MTFK
It specifically says to not lengthen the power wire, but obviously with my battery in the back this was not an option. Could that be the issue? I wouldn't really think that a lengthened wire would have that much of an effect..

Lengthening that power wire could burn your truck to the ground. Make sure you fully understand electrical circuits before modifying them.

 

[CC801]

Re: Power Drop

Go to the mini starter from a big block. Fits great. No ford style needed. Plenty of room for both wires i run 2g on mine. From alt to starter, starter to battery, battery grounded to frame. Engine grounded to frame. All 2g wire. There are 2 large terminals on the starter solenoid. One of them is a ground. Make sure both wires are on the same terminal.