Alternator Forum General Overview and Instructions

This forum has been created to allow users such as yourself to post (ask) questions and discuss matters directly related to Marine Electrical Alternators, Regulators, and Brackets. By sharing your questions, experiences, and lessons learned (good & bad), all may share and increase their knowledge base. ZRD will monitor and provide additional guidance as appropriate. This will not prevent users from having a lively exchange of information. To be included (question or response) send an email with 'FORUM' in the subject. If you need more guidance, see the Email Instructions link under Company / Contact Us tabs. If you need more guidance, see the Email Instructions link under Company / Contact Us tabs.


1.) What makes zrd alternators so special? - Very frequent question

Refer to our link under the FAQs Why are ZRD Alternators Special


2.) Will my tachometer work correctly when I install a new alternator or regulator? - Very frequent question

Refer to our link under the FAQs Tachometer Adjustment


3.) Rebuilt or Remanufactured? - Very frequent question

Many years back the words "rebuilt" and "remanufactured" had a specific meaning to each of them, because the industry, and society itself, was held to a much higher level of conduct. By definition, a rebuilt part meant the unit was disassembled, checked and any failed components were changed. If the shop was concerned with quality, then service items such as the brushes were also replaced at that time.

In contrast, remanufacturing describes a unit that has most, if not all, of its internal parts changed or rebuilt and only the case is original. This became a little confusing, since a true remanufactured alternator or starter could use the same rotor, but may be rewound and have the slip rings machined on a lathe. A good rule with an alternator is:   A remanufactured unit will have a new voltage regulator (if single stage internally regulated), diodes, rectifier, brushes and holder along with the bearings replaced. In truth, few, if any, rebuilders/remanufactuers do this. We have inspected so-called remanufactured units, only to find worn brushes, rusty diodes and old rectifiers and bearings. In many instances, the only component that was replaced was the internal voltage regulator, along with a good cleaning and painting of the case. Some people buy paint-jobs.

For this reason, we have developed an relatively inexpensive, high output, small case alternator as a direct replacement ( ZRD High Output Replacement Alternators ). This eliminated the need, problems, time, ... with repairing a worn or broken alternator. At least you know it will be done properly.

4.) I have a model _______ (fill in the blank) Engine and I am tired of loose alternator belts and black belt dust all over the place. Do you have a pulley and belt kit to upgrade standard equipment alternator belt to serpentine? If so, how much does it cost? Does it replace the old pulley or mount to the old pulley?

Usually this situation comes about from one of three scenarios - Improper installation (alternator & pulley alignments), improper or lack of tensioning, or constant overload. Refer to our FAQs and specifically to the one regarding belts and tensioning ( items 4, 5, and 6). Regarding item 6 - Based on your engine size, you may be in a situation that you are overtaxing your existing alternator (battery bank size in excess of 500AH and using a single alternator of limited output). If your battery bank exceeds 500ah, certainly by 600-700ah, you probably need our second High Output Alternator (ZCCJE1222, 220+ amps). Also, the cost to do the mods you were considering are as expensive as adding a second High Output Alternator in the first place. Again, the mod you were considering is a no go item. Contact us via a phone call for full details regarding your specific situation.