Alternator wiring

[Eliosso]

Need help in reinstalling my original alternator. Took it off without marking wiring colors. Does anybody have the pattern for color and related screws,  Model Prestolite
1) AC tap /
2) Ind.light term./
 (no wire was connected to this one)
3) Pos. output/
4) EXC./

would apreciate any help
Thank
Paul, Eliosso C34
PS: I know I should have taken notes  !!!!!!
SEN

[Ted Pounds]

Paul,

Try the following link: http://www.marinedieseldirect.com/universal/200157/universal-owners-wiring-diagram.html

I got to it by going to manuals on the home page then engine manual then  the link to the wiring diagram.  It's hard to read (at least on my screen) but it looks like Pos output is orange; Exc is purple; and the AC tap goes to the tach (can't tell the color but if you can see behind your tach you might figure it out).  The same info should be in your engine manual, if you got one with the boat.  If I go out tommorrow I'll try to remember to look at mine.

Ted

[Stu Jackson]

Alternator Wiring

Paul,

I'm in the process of designing my electrical system upgrade:

1.  new 100 amp Blue Circle alternator recommended by Jim Moe - I have it and it looks great

2.  new Balmar 612-H Max Charge smart regulator to replace my old AutoMac - lots of wiring challenges here: do I go directly from the alternator to the PDP or through the switch as currently wired, need and will increase wiring size by doubling up on the exiting #4's - my choice to make, still working on it, too long a discussion for this note

3.  installation of earlier purchased (1998) Link 2000 - need to remove old analog voltmeter and 1-25 amp non-shunted ammeter; and covering the old holes in the nav station

Planning going well, installation to follow.

As part of that I put together a special project book, with tabs for: notes,wiring diagrams, photographs, wiring harness, combiner and inverter charger (already installed), alternators and regulators.  Lot's of paperwork, great information and records for what it is that I now have, the changes I plan to make, and finally record documents of the final installation.

My Alternator tab has a sketch I drew of my OEM alternator, from the back.  I had removd it when I had my unfortunate alternator bracket mishpa:  see FAQs and Projects for the full story.

Pretend you're looking at the BACK of the alternator.  Either you have it out or you're the world's smallest person hanging out on the port side of the engine looking forward.

I'll try to do this physically, but this is not a WYSIWIG when you type in the message, so we'll see how it goes:

           Top of Alternator


               (0)  stator


                        (0)  BAT +(red output)


                     (0)  field


               (0)  ground

       bottom of round alternator              (looking forward)


(0) = stud with nut for wire connection.

I don't have a good enough photograph of this to show you, so I hope this helps.

Stu

Don't know if this is still working, but you may want to try:

www.film.queensu.ca/CJ3B/Alternator.html

[Stu Jackson]

Well, the physical stuff didn't pan out.

Try looking at the (0)'s above and make them curve to the right from the top to the bottom.

With the wiring diagram previously recommended, you should be able to match the wires with the function on the back of the alternator.

Stu

[Eliosso]

Stu, Thanks
I too will be installing all new stuff,(well founfd someone to do it for me , no time), got the alternator that Moe recommended, a balmar regulator, statpower 40 charger with remote, 1000watt inveter,auto charging relay, link 10, auto pilot simrad,Boat was a great deal but not equiped which is what I prefer anyway. Going in the water on the 3rd.
Thanks for the info
Paul

[Stu Jackson]

Paul

WOW, that sounds great,  She will be a new boat by the time you're done.  of course, you've got the batteries to support all that fun, right?

It's amazing how much "not having to worry about your electrical system" makes worry-free boating, and contributes to so much more fun.

Fair winds,

Stu

[Eliosso]

Stu
have already installe 4 Trojan 105 for a total of 450 AMPS plus another starting battery to come that will be installed just behind the engine. What do you have for a starting battery?
My present is a dodger, bimini and full enclosure , can't wait, will send pics when done. Am installing 2 outboard teak swim platforms on the transom , 1 on each side of the ladder. Saw this installed on another C34 , should make life alot better for boarding with the dog and all.
Paul

[Stu Jackson]

Paul

Our starting battery is a West Marine 60 ah starting battery.  Nothing more than that is needed for our small engines, has been working fine for the past two years.

Stu

[Eliosso]

Stu, did you check the total amperage from the blue circle alternator?? I seem to be getting only 45 to 50 amp.
Paul

[Stu Jackson]

Paul

45 to 50 amps is more than twice what you'd get from the OEM stock alternator.

My Blue Seas is not yet installed.  I seem to remember around 100.  But that output would only be expected for a very short time on almost completely dead batteries.  If you're using the 80-50 rule on charging, why would you expect more output from the alternator?

If your batteries were reasonably charged, 40 to 50 amps may be all they can accept (i.e., need).  Think of the "system" not just the parts.  With your 450 AH battery bank capacity I wouldn't expct more than the 50 amps would be necessary.

Stu

[Roc]

Here is a chart I made from information from one of the battery manufacturer's websites.  I made a reduced copy and laminated it.  It now is attached near my batteries for easy reference.

Roc-

%   VOLTS   SG
100   12.70   1.265
95   12.64   1.257
90   12.58   1.249
85   12.52   1.241
80   12.46   1.233
75   12.40   1.225
70   12.36   1.218
65   12.32   1.211
60   12.28   1.204
55   12.24   1.197
50   12.20   1.190
40   12.12   1.176
30   12.04   1.162
20   11.98   1.148
10   11.94   1.134

[John Langford]

Stu,
I was wondering if you are running your new 100amp alternator with the original 11mm (7/16") wide alternator belt. I have a 110amp Leece Neville alternator (with Heart smart regulator) and I am having trouble with belt slippage (oscillation of tach needle, voltage oscillation and up and down amp readings on the e-meter). I am using a good Gates green line belt and I am tightening the belt appropriately but it is still starts slipping after a short period. As there is no obvious belt wear and the belt appears to be running smoothly, I am convinced the pulleys are lined up. There is a small amount of cupping in the belt but the belt is not bottoming out in any of the three pulleys. Also, I am rarely discharging below 50 amp hours (one night on the hook) so I am hardly asking the alternator to work that hard. My e-meter tells me that it is not putting out much more than 50 amps even at the beginning of the charge cycle.

Any ideas about what the problem might be or possible solutions? I tried some belt dressing but it just made a gummy mess which I have completely cleaned up (including scrubbing the pulleys with acetone) and replacing the 6 month old belt which the NAPA guy thought was glazing a bit from slippage...it still looked good to me after I cleaned the goop off it.

Cheers,
John

[Ray & Sandy Erps]

Hello John,

For what it's worth, I'm using the original belt on the new 100 amp alternator.  I installed the alternator in June.  Probably have 50 hours on it or more and have had no problems.  Our biggest discharge was 50 amps for three days on the hook with the fridge running occasionally and the existing belt handled the 50 amps that the new alternator was putting back into the batteries just fine.  I figure I'll buy a Gates industrial belt soon, but wanted to see how well the old belt would handle it.

Ray

[Stu Jackson]

John

No, I haven't installed the new alternator yet, so can't give you a definitive answer.

I'd also recommend going back to Ron Hill's old conversations.  I believe he stepped up to a 1/2 inch belt and recommended that idea when increasing the size of the alternator.

In the meantime, you could use the amp manager feature on your regulator (if you have one with that feature), which is what Steve Lyle did when he first installed his larger alternator.

Also, any newer alternator will most likely put a bigger load on the belt, even though they run free, the new alternator will not have been as "broken in" as a 15 year old OEM alternator.

Stu

[John Langford]

Thanks folks. Interesting idea about governing the alternator, but asking for 50 amps is hardly a major load for a 7/16" belt. Ron, one consideration when moving up to a Gates belt is that a friend at the club suggested that the Gates is possibly more prone to slip because of the harder material built into the side of the belt. I am actually going to try a cheaper, softer belt without teeth (the size of the pulleys apparently doesn't demand the teeth). We will see!

Cheers,
John