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Sounds like a good plan. (y)

Don't know what I'd do without my DC clamp-on ammeter. You probably remember the days when you had to insert an ammeter into the circuit by cutting a wire -- kind of like old skool dash mounted ammeters. Nothing like full charge/discharge current running behind the dash!
 

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Are you jumpering terminal 2 to the BAT terminal on the alternator? This is a common trick and it works OK if you aren't needing lots of amps. But term 2 is the sense line; it tells the alt how much voltage to put out. Best practice is to run the sense line to the fuse block so you get 14.7 volts at the fuse block.
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #23 · (Edited)
Ok, got my new CS130 yesterday, and just finished installing it. WAY BETTER performance, but still not "out of sight" better. I tested at 2,000 engine rpm, since that's about where I drive most of the time (700R4 and Jag 2.88 rear end). Battery was low, would not start...put charger on at 10 amps for about 10 minutes, started up cold, all accessories off... then loaded it up with A/C, three fans, radio/amp, interior lights, headlights, under hood lights, and trunk lights. Here are the results. These tests only took no more than 10 minutes, and when I shut her down, residual voltage was 12.66 on the battery.. Then I put the charger back on and it still showed about 1/2 charge (gauge position on the charger)... In any case things are WAY better with the output voltage at 14.31 at full load. Oh, by the way, I learned a few years ago about a trick to improve fan performance, and that is to wire another 10 gauge directly from the alternator to the fan controller-power input terminals through a 40 amp circuit breaker. The fans run noticeably faster when they come on as opposed to going to the fuse box and back to the fans. As a reminder, the fuse panel and the battery are in the trunk.

And of course it's Chinese, and the case was chromed after the threaded ear was tapped, causing me to run my tap through it to clean up the threads so the dang bolt would even go in....

What is strange and disappointing is that with a "low battery", and virtually no load except the ignition, that although the voltage was good and a lot higher, at 14.86, only 6.3 amps are actually being delivered, and the output of the alternator is only 12.3 amps. Weird. Leads me to believe that no matter what, I'm only going to get 6+ amps to the battery no matter what, since there is hardly any difference between the no load condition and the fully loaded condition. I will charge the battery to fully charged, and see if it goes to near zero after putting the "starting discharge" back in....

I did have a potential problem with clearance of the output terminal, since it's on the side and not the back of the alternator. It's only about 1/2 inch from the radiator connector/hose, but I cut the old rubber "cover" for the terminal (three output wires and it wouldn't fit, and tie-wrapped it back on with the flex wire cover.

Thanks for all the input, guys.... we shall see if I don't have to get a jumper the next time I stop at a 7-11 (or anywhere else, for that matter)... and it's still hitting nearly 100 degrees in Austin... grrrrr.

Also, thanks for the tip, potvinguy... Some day when I have nothing else to do I might try to string another wire to the trunk, but for now..........

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Well, it sure is purty!

12.66 volts at the battery with no load should not cause any problems. I just checked my truck that's been sitting for almost two weeks. It's 12.44 at the battery and I know it will spin the engine over with authority.

Have you checked current draw on the battery with ignition off and engine not running? And did you have a parts store do a load test on the battery?
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #25 ·
Yes, my parasitic draw is 0.7 amps.. and about a year ago I stopped by a parts store and they did a test and said that the battery was just fine but I know it's got a little bit of a problem. For a long time I haven't been able to get any more than about 15 seconds of crank time before it won't start. I'm not sure the guy that was testing it knew what the hell he was doing...
 

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Man, 700ma sounds like a lot. Which load is drawing that much? Clocks and radio memory probably don't draw 25ma.

Just found this on the Optima Batteries site:

We suggest a 25-milliamp draw is acceptable and anything that exceeds 100-milliamps indicates an electrical issue that needs to be addressed.
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #27 ·
Well I've got the dash mounted voltmeter, security system, remote fob operated door openers, and radio memory. That's all I can think of right now. I guess I could put a switch on the voltmeter and the radio....
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #29 ·
So what happens if you disconnect the neg bat cable overnight with the bat voltage and cranking ability???
No problem at all starting.. problem with SI10 is that it didn't put out enough amperage at slow speeds and stop and go traffic with a/c on to add any energy to the battery.... but as I mentioned above, at best, even after charging till the charger was cycling off and on, I wouldn't get much cranking time.. maybe 15 or 20 seconds..
 

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Unless you have Prius electric AC the only electric power an engine driven AC system is using is a relay or two and the heater’s fan.

The big issue with AC when it’s running it pulls the idle speed down, however, there should be a relay that engages to pull the idle up one of the benefits of which is higher alternator output as the revs come up.

Then again Apollo 13 is a good class in unnecessary load shedding.

Bogie
 

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1949 Ford Coupe RESURRECTION
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Discussion Starter · #31 ·
Bogie......And the compressor clutch.

But here's what happened today... charged the battery last night just for the hell of it.. residual sitting at 12.45.. cranked it up, went for a 25 minute drive, mostly highway... Battery voltage readings on dash mounted two decimal voltmeter, 14.2 to 14.6 volts depending on rpm., but amps drops fast below 900 rpm. everything running except the headlights. Came home, turned her off, went to restart, and NOTHING, except a couple of the dreaded "werrrrp, werrrp......."... so after a quick charge, I made a journey to the battery store, and $177.62 later, I have a new 700+ amp battery. This hopefully should end the headaches...........THANKS everybody.. and it's still 95 degrees in Austin... grrrr
 

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I used to live in Houston, just can’t do the combo of heat and humidity. I’ll take a temp/humidity at 120/05 any day in Muroc over 96/90 in Houston.

I put deep dwell marine battery in my 350, S15 which is mounted in the rear of the bed behind the right wheel well. That thing cranks the engine with a purpose, let me tell ya.

Had the Harley out for shakedown cruise this morning the new tires are sweet. Need to go back and peek at the electrical harness that got tore up when the rear tire blew. The nav light on the bottom of the fender isn’t lighting again though it did on the electrical test a few days ago. I never felt the 2-1-2 exhsust I put on years ago sounded right so while the exhaust had to come off to get the rear axle out there while there was time to wait on new tires arriving I did a deep dive into how that exhaust system works and concluded that if I drove a length of 2 inch exhaust tube to bridge the “Power Box” through from the tail pipe end I’d have a 2 into 2 straight through.
The pipes are probably too loud though a WSP cruiser passed me and didn’t appear to take notice. Oh Yeah, the best is on!

Bogie
 
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