HO Alternator For a Mercruiser in a Sanger

(noquams) · (noquams) **Join Date: Apr 2002** 05-10-2006, 12:13 PM

I have been watching an reading every post relating to HO alternators. I have yet to see one relating to someone adding one in a Sanger or Mercruiser. I took mine out and looked into getting it rewired. due to it's size it is maxed out. It tested @92 amps not sure on the rpms when tested.
I would like to add a larger capacity alternator but have been unable to find one that would simply bolt in. Can anyone help with a place that sells a bolt in or how to modify things so one can bolt in. Thanks is advance.

(acurtis_ttu) · (acurtis_ttu) **Join Date: May 2004** 05-10-2006, 12:34 PM

You can have a machine shop build you another bracket. From my research ~135 amp is usually about as big as you can go w/o any bracket alterations. Try soundillusions.com for a good rebuild, btu be prepared to pay....your lookin in the $400-500 range. Why do you need a bigger alt? What are you running?

(noquams) · (noquams) **Join Date: Apr 2002** 05-10-2006, 12:46 PM

To be candid I'm not 100% certain I need a larger alt. I have a 5 chanel and a 4 chanel Kicker amps pushing 1 sub, 4 6x9's and 4 component speakers. I have three batterys now. I believe having a larger amp would push more amps at idle or slightly higer to charge when needed.

(acurtis_ttu) · (acurtis_ttu) **Join Date: May 2004** 05-10-2006, 12:58 PM

Your stock alternator should be fine, IMO it's not worth the extra $$$$. Are you seeing a large voltage drop when the volume is turned up? Does it eventually return back to normal (13.5-14.4)?

90-105 amp alts are probably the best alt for the $$$ b/c you can get a reasonable amount of amps at low RPM and decent output at high RPM w/o have to make any major modifications.

Make sure you have adequate wiring to your amplifiers.....if they are seeing low voltage they will pull more amps and drain your batt's quicker as well as more strain on the alt when running.

(ss1234) · (ss1234) **Join Date: Jul 2005** 05-10-2006, 1:58 PM

I have a Sanger DLX and the previous owner fabricated a bracket and hung an additional alternator off the motor, (not a HO alternator). This additional alternator only powers the stereo, and runs to (1) battery. The system has (4) amplifiers. I would have to check the wattage, but I know they are not small 2-channel guys. Never had an "insufficient power" issue with the stereo. Also never have to worry about the stereo set up interferring with the boat starting.

I see you have a DLX (from profile). I have a '96, but I could send you a picture if it would help.

(noquams) · (noquams) **Join Date: Apr 2002** 05-10-2006, 2:07 PM

I would really appreciate a picture. I believe most of my low voltage issues stemmed from using a single battery at a time. I have a Perko(sp) switch and can use one at a time or both. This year I will have at least two and two maybe theree and one. The one used as a back up in the event I run the others down enough to not be able to start the boat. Seems most of the modifications done to systems with photos and explanations were on non Mercruiser engines. Any photo's or explanations would be appreciated.

(ss1234) · (ss1234) **Join Date: Jul 2005** 05-10-2006, 2:19 PM

I have mercruiser. I did not do the original modification, but I've been through it to where I know 90% of what was done. I'll shoot some pictures and post tomorrow with some additional explanation

(acurtis_ttu) · (acurtis_ttu) **Join Date: May 2004** 05-10-2006, 2:40 PM

The main advantage of using multiple batteries is more run (stereo) time w/ the key off and as a backup for starting, not to increase voltage. Your issue more than likely does not stem from using only one battery. You should really check your stereo system first and make sure that your problem is your alternator....There are quite a few reasons why you coudl be seeing low voltage. Also I would not use the guage on the dash as your testing measure.

(ss1234) · (ss1234) **Join Date: Jul 2005** 05-11-2006, 12:18 PM

Chris-
here ya go, she's not pretty, but she's paid for and still works....

Lower alternator shares a mounting point with the original (above) and a Stainless bracket was fabricated to support the lower mount. The stainless bracket mounts to the same holes as the original bracket. Add a longer belt and done.

My amps are mounted on a board that is mounted to the top of the compartment under the observer seat. One battery and a disc changer mounted in the same compartment. There is another amp mounted behind a custom sub enclosure that is wedged under the dash.

Hope it helps.....

Upload

(noquams) · (noquams) **Join Date: Apr 2002** 05-12-2006, 3:53 PM

Steve,
Thanks for taking the time to post the photo's. That seems like a good way to seperate things into two systems.

(ss1234) · (ss1234) **Join Date: Jul 2005** 05-15-2006, 10:28 AM

No problem. It's worked for me so far. Hope you get your system figured out.