BlackMax 135 V6 (1991) rectifier

Juke

Recruit
Joined
Sep 3, 2020
Messages
5
Hi,

the rectifier burned and I replaced it. The battery charge is still not working. I'm pretty sure I connected the wires right but still, does anyone have wiring diagram (or photo) about connection. The new part is 100% right. Or if someone has idea what else might be broken. Help!
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,559
Check the maxrules website for a wiring diagram. Not sure you will find one for a '91, but a 1980+ should be very close.

Do you have a plain rectifier, a 40A voltage regulator or twin 20A voltage regulators? Those are the choices for that motor thru the years.
 

Juke

Recruit
Joined
Sep 3, 2020
Messages
5
It's plain rectifier, not twin. I already checked from maxrules. The problem is that there is two red wires coming to +. In diagram only one.
 

Dukedog

Captain
Joined
Oct 6, 2009
Messages
3,496
your motor will be same as any 16 amp system.. make them up together.. ALL RED wires anywhere on that motor will have a constant, unswitched 12v from battery... one goes to tha regulator and one should go to tha battery at start solenoid.. most will start from starter solenoid battery post.
 
Last edited:

Juke

Recruit
Joined
Sep 3, 2020
Messages
5
What voltage should come to rectifier while motor running? Now its something like 12,8 to 13,0 depending of rounds, Is that too low,? Is that the reason why charging is not working. Something wrong with the stator? Is there a separate charging circuit? Or just one for both charging and ignition?
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,897
Assume your pickups under the flywheel are similar to lower HP engines: One set of coils for triggers, another for generating voltage to charge the capacitors in your CDModule or CD system, and a third set for battery charging, all independent, non related (other than having insulation melt on the interconnecting wires and a short circuit resulting....you did say your rect/reg burned up.......) circuits.

Output voltage of rectifier/regulator depends on rpm and load current. A 16 amp red stator on a smaller engine is rated 16 amps max at WOT, but the voltage won't be 14.5V. Conversely, when a good battery is nearing full charge and the rpms are at max, the current will be in the low single digits and the voltage will have risen to 14.5V....serv. man. number. As long as your running (over 1k rpms) and battery voltage exceeds the value you had with the engine off, your charging circuit is working.

The question is, what kind of load is it driving? First thing I'd do is have the battery "load" checked....load checking forces high current out of the battery while monitoring terminal voltage. When the battery has a dead cell or sulphated plates, it can't do things like put out 300 amperes with 11V across the terminals, the numbers I use for pass/fail on what looks to be a good, fully charged battery.

Another possibility is that the supply from the stator can't deliver adequate current to the rect/regl because the interconnecting connectors on the wires feeding the rect/regl, overheated and as a result are high resistance...discolored insulation over the connectors is the clue to that and as said earlier, wires from the stators need to be inspected for melting insulation and shorts.

These thoughts keep coming to me....my third edit: Another possibility is that the "varnish" coating/insulating the wires making up the pickup coils in the stator(s) may have overheated and allowed wires to short together. It only takes one such wire, making a complete loop of current to kill the stator output.

The physics of the "transformer" are such that each turn has a given voltage it maintains and if that voltage doesn't develop, all the energy generated with in the device is applied to that loop, trying to establish the Volt/turn rating of the device. Hard to check with an Ohm meter as the manual's posted testing resistance for stators is fractional ohms.....but the two AC feed wires are to be insulated from chassis ground which can be easily Ohmed out.
 
Last edited:

Juke

Recruit
Joined
Sep 3, 2020
Messages
5
Thanks, this helped a lot. Battery is brand new, so probably that is ok. I think something happened is the charging circuit ( if that is a separate one) and that caused the rect. burn. Old engine, I will not prepare it but load the batteries with solar cell instead :). No problem while having some days fishing trip. By the way, I writing from Finland and like to thank you folks about help. This is really good forum!
 

racingdave

Cadet
Joined
Aug 2, 2020
Messages
26
I HAVE THE SAME SET UP ON MY 1990 BLACK MAX 135 YOU ARE NOT GOING TO SEE A LARGE OUTPUT FROM THAT CHARGING SYSTEM I TRICKLE CHARGE MY BATTERY EVERY OTHER TIME OUT TO KEEP THE BATTERY UP AND MONITOR THE CHARGING VOLTAGE AT CRUSING SPEEDS YES IT CHARGES ANYTHING OVER BATTERY VOLTAGE 12.6 AND ITS WORKING.THOSE MOTORS HAD A VOLTAGE REGULATOR PROBLEMS THEY WOULD GET HOT AND BURN UP THEY WOULD ACUALLY HAVE A SPOT ON THE POWERHEAD THAT SUBMERSED THE REGULATOR IN WATER TO KEEP IT COOL YOU DONT HAVE THAT STYLE AND YOU SHOULD BE HAPPY ABOUT THAT THEY CAUSED FIRES.Having only a 16 amp stator dosnt help either those modles offer a 40 or 16 amp stator.ANY WAY ANYTHING OVER BATTERY VOTAGE AND IT WORKS AND ALSO THE YELLOW WIRES COMING FROM THE STATOR GO TO THE RECTIFIER.
 

Juke

Recruit
Joined
Sep 3, 2020
Messages
5
Thanks, I will check that while next time ay the bost. I actually measured tha voltages from the battery end, showing 12,8 and the echo shows the same. With 9,9 hp trolling motor the echo shows 13.1 V.
 
Top