Well, today I jumped in my truck and it cranked slowly then started the lovely clicking sound. I jump started it and it started right up. Only took about 45 seconds of charging off the other car to start right up.

For the past week it has been cranking slower and slower. The starter is new and the truck charges at 14 volts, even at idle.

When get in the truck in the morning and turn it on, after the glow plugs go out the batteries rest at 10.5-11 volts.

I checked for any current draw with the truck shut off and get .002 amps.

My battery cables look to be in good shape.

Am I right in assuming that my batteries are on their way out?

 

Check the output terminal on the alternator, big wire fastened with a nut.
I burnt mine off while plowing snow a couple weeks ago.
Charged the batteries OK, but not full.
Had slow starts in the morning for two days before it fried.

Get the batteries load tested with the ground wire removed from one of the batteries during the test.
Test each battery individually.

Load testing will tell you the battery condition and the charge level.

I have an aftermarket 150 amp alternator.
A while back my truck was rather tempermental about starting.
So down to the auto parts house I went.
Salesman hooked the tester up to the alternator first, charging 14 volts and 6 amps at 1500 RPM.
OK shut it off, unhook a ground, hook the battery leads to the first battery.
Battery good, charge low.
Test second battery, once again battery good charge low.

Salesman tells me alternator good, output good.
Batteries good, need charged though.

I say get me a new alternator, that is a 150 amp unit, if it was good it would be charging more than 6 amps with low batteries.

Next day we changed the alternator, this time the alternator was putting out 14 volts and 100 amps when we checked it at 1500 RPM.
No more starting problems.

When your batteries are low, if the alternator is not putting out at least 70% of what ever amperage it is rated at, the alternator has a problem.

 

I stopped by Napa, the guy told me to go to a specific Shucks to get the truck tested.

Went there and the guy would only test on battery at a time cause I didn't know if I could stat it again. One battery came up bad. Could only get 163 amps out of it.

Went back to Napa, they can only warranty the one bad battery. They only had one battery in stock, and I'm short on cash so I just replacd the one under warranty. They can't replace the other one under warranty unless it shows up dead on their tester. Friday I will see about replacing the other battery.

I'll see how good it starts in the morning.

 

The truck has been starting better then I've seen it start, even when my friend owned it. Guess it was just the battery, I'll replace the other one on Friday soa have a new pair.

 

Not sure what your vehicle is, but it does good to take apart and clean ALL wire connections, these things are really picky about corrosion. It took me almost 3 weeks to figure out that mine were corroded and not charging the batteries well enough. Cleaned them and charged them and it starts every time faster than ever. The only problem that I am having is that the charge meter (87 f-250 6.9) drops fairly low if the headlights and/or the fan is turned on even when running. Does anyone (read Dave. LOL) know if this thing has an internal voltage regulator or external?

 

I will be buying the needed terminals and wire and have the guys at work assemble new battery cables for me.

Then I will have new cable, starter and batteries. Unless the glow plugs take a dump on me I shouldn't have any starting problems for awhile.

 

The stock charging system has an external voltage regulator, located on the passenger side inner fender right behind the battery.

 

Yep, and I have a spare in both my pickup and my SVO. I also have an aftermarket voltage guage in the pickup so I can keep an eye on things.

 

Does it make sense that the voltage regulator has a problem with the high load side? Wouldn't that cause a drop in voltage even from something as minor as headlights and/or fan?

 

I am not sure if Ford changed the wire size running from the engine compartment on the 87 body style, I show a much lower voltage when the heater motor is on high than I do when it is off. I have installed relays on my headlights so there is a very low draw on the stock wiring when the headlights are on.

I atribute my lower readings to the small wire size Ford used when they did the original wiring harness since my volt meter is tied into the original wiring inside the cab.
I keep wanting to do a rewire, but time seems to be slipping away to fast for me to get it done.

I will tell you that running relays on the headlights made a big improvement on how bright the headlights are, and the headlight switch does not get near as warm as it used to. Also the voltage drop on my volt meter is much lower when the headlights are on.

The heater draw may be due to the fact your heater motor is about worn out.
Worn bushings in the motor cause the draw to go up, even more if it happens to let the blower wheel touch the side of the heater housing.
Not sure about the 87 model, but on the 86 there are only 4 bolts holding the heater motor in.
Pulling it out to check for play in the shaft is easy.

 

Sorry to say they did not change the diameter. Basically the same deal just a different firewall connector. The 87 has the updated GP wiring harness but the rest was the same just routed a little different. I had the same problem with turn on the blower and the gauge would go down. I changed the #6 wire and put a bigger wire off of the altenator made a huge difference. A plus was from plowing and having the headlights and lightbar running never would get back to normal for like 10 minutes now it is very quick recovery.

 

could someone give me an idea or two of what I need to do to help with this? How can I check the blower motor? what do I need and how do i wire what type of relays to the headlights? Which wire off of the alternator do I need to change to a bigger wire?

 

Blower is easy there is 3 or 4 screws it pulls away pretty easy be careful most of the blower wheels (squirrel cage) are brittle and the fins break easy. Just give it a spin if it wobbles or is hard to turn time for a new one. Secondly does your blower work at all settings? If it does very good if not the resistor pack is shot and those are 18-25 dollars from Ford.

The #6 wire is the supply wire from your passenger side battery to the starter solenoid but only really supplies one small wire to your starter. The rest of the bundle attached to the starter solenoid is the GP supply LH and RH bank power for cab interior and lights head and markers. The altenator charging wire is in the mix and your brake lights are powered seperate I think that is a Dark Blue wire. The charging wire will be the largest coming from the alt. and has a nut holding it, the other 2 are small and create your "field" for the alt. to work.

Before you mess with the alt. make sure that #6 wire is in good shape might be corroded at the terminal or even at the solenoid. If your not plowing snow or running a bunch of lights probably would not double things up or make things bigger.

Think of electricity is like water moving through pipes bigger the pipe more flow less resistance. That #6 wire can be a pain because it may look good but under that coating it could be corroded. That wire also pulls double duty it supplies your truck and also charges the batteries. Stock is to small my opinion.

 

Out under the hood on the passenger side you should see the blower motor.
Four bolts hold it into the heater housing.
Pull those bolts out and remove the blower motor.
Then check the shaft for play and inspect the squirrel cage for signs of rubbing.
I bought a replacement blower motor from Advance Auto, the price was not to bad, under 50 dollars if I remember right.

At Advance Auto is where I bought the relays for the headlights.
They each have four terminals, power in, ground, power out and trigger.
You need two, one for low beam and one for high beam.
I also bought heavy duty headlight sockets, they have 12 AWG wire instead of the 18 AWG Ford used.
I ran 8 AWG wire from the battery positive post to an inline fuse (30 amp fuse) then to the power in on the relay.
I cut my stock headlight wires near the windshield washer tank and added terminals to attach them to the relay trigger terminal.
The power out terminal has two 10 AWG wires, one for each headlight.
The ground wire on each headlight socket is attached to 10 AWG wire that runs back to the battery negative terminal.
The ground terminal on each relay is attached to a 12 AWG wire that also runs to the battery negative terminal.

I know this sounds complicated, but it is really easy to do.

 

Thanks Dave, That actually doesn't sound all that complicated. I will see if I can get a chance to look at it this weekend.