Electrical prob.
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Lead Driver
Joined: Mar 2008
Posts: 7,188
Likes: 384
From: Near Los Angeles
Electrical prob.
I just came from the tow truck, so I haven't had time to check anything yet. I just thought someone would immediately know the problem before I started checking.
I have a new 100 amp alt with less than 5k on it. Today the belt started screeching like mad. I could not accel w/o it wailing!! But I had zero tools. It was one of the remaining bugs from the engine swap. The belt would 'yelp' when started. I noticed the amp gauge would jump a bit toward C on acceleration, higher than usual.
I hit the auto parts, got a wider belt, put it on, and screeching stopped, but the gauge still jumped on accel. I got about 3 miles before it died. Dead. Not even a click. The tow truck driver put a charge box on the battery, still not a click. No dash lights...nothing.
The belt slipping is unrelated. If it was the alt, the charge box would have allowed me to move it. I'm thinking it must be the solinoid relay between batt. and ignition.
Any ideas?
I have a new 100 amp alt with less than 5k on it. Today the belt started screeching like mad. I could not accel w/o it wailing!! But I had zero tools. It was one of the remaining bugs from the engine swap. The belt would 'yelp' when started. I noticed the amp gauge would jump a bit toward C on acceleration, higher than usual.
I hit the auto parts, got a wider belt, put it on, and screeching stopped, but the gauge still jumped on accel. I got about 3 miles before it died. Dead. Not even a click. The tow truck driver put a charge box on the battery, still not a click. No dash lights...nothing.
The belt slipping is unrelated. If it was the alt, the charge box would have allowed me to move it. I'm thinking it must be the solinoid relay between batt. and ignition.
Any ideas?
Senior User
Joined: Mar 2010
Posts: 231
Likes: 0
From: Lakeland
I have heard of a battery getting reverse charged before. Usually it's on something like motorcycles where, by some fluke the engine gets started and run in a reverse rotation. It could be a bad connection or a corroded wire. I recently changed my negative cable and fixed a intermittent starting problem. The negative cable was severely corroded through about half the length of the cable. A bad plate in the battery itself. I'm no expert by any means and this probably isn't much help but that's all I got right now.
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Lead Driver
Joined: Mar 2008
Posts: 7,188
Likes: 384
From: Near Los Angeles
As soon as I poked around I found the problem. The battery still had ample power. The main wire from the alt. to the solenoid was fried, and I mean toast, crumbling as I picked it up!! I changed alts. a ways back, to a 100 amp one, and did not up-grade the wires carrying the juice. Oops. That was not mentioned in the Napa Instructions! I just spliced in a beefyer wire, and down the road I went. But my trusty oem amp guage is not working. It shows a constant D for "discharge", which startled me at first, but it is still running. I hooked up my dwell meter, on the volts setting, and it showed 12.5 coming off the alt, and the same at the battery. I will check the fuses tomorrow. Maybe I'll have to pull another instrument cluster from the bone yard, or go with an aftermarket one.
It's funny, but my entire garage has become a storing facility for this vehicle. I fried a wire. No problem. I just went into the shelf with wires for DD, and boom, there we go. Spliced to life. The factory splices look nicer, but once they're covered with elect. tape, no one is the wiser.
It's funny, but my entire garage has become a storing facility for this vehicle. I fried a wire. No problem. I just went into the shelf with wires for DD, and boom, there we go. Spliced to life. The factory splices look nicer, but once they're covered with elect. tape, no one is the wiser.
Postmaster
Joined: Dec 2006
Posts: 3,603
Likes: 10
From: Spokane, WA
Yup...what gfw1985 said. I'm currently working on a low voltage problem with a boat I just bought. I cleaned and greased all the battery connections...may have to change the cables though...but I will find out when I run it again.
Post Fiend
Joined: Dec 2007
Posts: 8,521
Likes: 16
From: Lost
X3. 12.5V is not enough to keep the battery charged. The battery is *actually* 13.2V, when fully charged.
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Lead Driver
Joined: Mar 2008
Posts: 7,188
Likes: 384
From: Near Los Angeles
My NAPA alternator, $100, lasted 4500 miles, 10 months. I don't think I can return to that napa store, because I told them they use the same rebuilder as the discount stores, but charge double, and gaurantee for half as long. They are trying to sell their name.
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Cranky Old Guy
Joined: Mar 2008
Posts: 3,562
Likes: 6
From: Raphine, Virginia
I would think the 100a alt would do the job. You do have the electric fan running off a relay and getting fan power from the battery right? The alternators function is to charge batt when voltage drops, not actually power anything. Might be a good idea to load test that battery to check it's condition. Some electric fans can pull a butt load of amps. Never owned a MSD igniton, but have read they can be sensitive on how they are getting power, like sharing a circuit with other loads.
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Lead Driver
Joined: Mar 2008
Posts: 7,188
Likes: 384
From: Near Los Angeles
I have the MSD direct to batt., and directed. The fan relay is hooked to the starter solenoid. When the fan kicks in, engine hesitates. I am changing to a 100 amp alt. Any suggestions where I should run the fan from?
Cranky Old Guy
Joined: Mar 2008
Posts: 3,562
Likes: 6
From: Raphine, Virginia
Sounds like you have it covered on the connections. Just need to get that voltage up a bit. Still load test that batt, and the fan could be messing with your voltage readings due to alt. not able to keep up. Without the fan running you should read at least the 13.5 volts across the batt at idle.
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Lead Driver
Joined: Mar 2008
Posts: 7,188
Likes: 384
From: Near Los Angeles
Interesting info: While shopping around for a new alternator, I've been reading on PowerMaster and Tuff Stuff sites. I was a little surprised to learn that when they call an alt. 100 amps., that means it produces 100 amps at about 6k rpm! and only 70 amps at 2400 rpm. Their site does give conflicting information. So, at idle, it's pumping what, around what? maybe 40-50 amps?
I just learned something.
I just learned something.
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