Electrical question for Dave s.

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Feb 4, 2007 | 07:41 PM

davelong667

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From: Halstead, KS

Electrical question for Dave s.

I recently got new battery cables, 2 new 1000 CA batteries (850CCA), and with the gear reduction starter, she turns over like a champ now. Starts even in the coldest temps. Now.... Here is my issue, While driving around, my battery gauge is at about 5/8 the way up, which is good, and it charges at 14.5 or so volts, I can turn on the high beams, low beams, windows up and down (both) and it barely budges the charging gauge much. BUT, as soon as I kick my heater blower onto high, it whips my batt. gauge down 2 or 3 notches and keeps it there. Why is my blower motor creating such a load? It blows niclely, is my heater core clogged, causing it to bog down? whats going on?
Thanks!!

Feb 4, 2007 | 08:27 PM

PLC7.3

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From: Manitoba

Pull the fan and see if there is any debis in the heater plenum, I would think it should do a fairly good draw but check it or have it checked.

Feb 4, 2007 | 08:50 PM

davelong667

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From: Halstead, KS

I might just pull it off tommorow to see what I can see. If its clear, then maybe Dave S. has an idea of whats wrong, after all he is a Jedi IDI Master.

Feb 4, 2007 | 10:23 PM

KJLYPW

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From: Powell River B.C.

Are you running a volt meter or an amp meter? An ammeter normal shows how much charge is going back into the battery, with the high load on with the heater, it would not show as much charge.

Feb 4, 2007 | 10:58 PM

roamer37

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From: Grosse Ile Mi.

Check your battery voltage with a real volt meter.. and see what it really is doing.. also find the heater resistor block in the heater case unplug it see if you have any melting in the plug then remove the block it should have two small screws holding it in the heater... see if anything is melted broken or other wise damage.. check across the resistors with a ohm meter make sure they all work ... my guess is your going to find the resistor block is toast.. and you have more then one speed running on the fan motor..

Feb 5, 2007 | 12:20 AM

Dave Sponaugle

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From: Nutter Fort, WV

My volt gauge shows a good drop as well, I think a lot of it is where I taped into the electrical system with the gauge.

I am not real happy with the wire size Ford used for the wiring harness in several areas in my 86. The small conductor size causes a lot of voltage drop to big draw items. Two specifically are the headlights and heater motor. I already switched my headlights to run off relays, which has resulted in much brighter headlights and longer lasting bulbs.

Feb 5, 2007 | 05:10 AM

tjc transport

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From: Marlboro Mental Hospital.

the 87-90 trucks used too small of a wire to feed the blower motor, and when you turn it on high, it pulls allot of amps to run. every one of my trucks did the same thing, with 2 of them melting the wire off of the fuse block.