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how to test rectifier/regulator 582905

vanceboroguy

Contributing Member
I'm kinda short on play money now and need to know how to test rectifier/regulator part# 582905 on 150HP evinrude. Seems, these little suckers are $200 bucks a pop. Wolud like to know if this is really my problem before I shell out the dough. I have little to none knowledge of these charging systems. Anyone out there got a good used one that they will part with? Battery on boat reads same volts, motor running or not and Tach works fine.
 
What does this mean? The meter should indicate continuity in one direction but not the other. Therefore, if a reading is obtained in both directions,or if reading is not obtained in one direction, the diode in the rectifier is defective. Are they referring to the direction of leads or the direction of meter needle travel when they say if reading is obtained in both directions. Thanks
 
Are you sure 582905 is the correct part?

I find 0583529 in the parts list and that is only $108

I am not aware of any way of testing a regulated rectifier other than saying that if the stator is OK and you don't get any output from it its dead.

Check the stator coils for continuity and also check you get a sensible AC volts out from it.
 
I will see if I can understand the manual for stator test. I,m ignorant to basic electicial troubeshooting. I did find one for around $100 after I posted for this part#. I was under the understanding that if tach worked stator is O.K.? Thanks for reply!
 
Reading in one direction and not the other (checking a diode)....... this means that you have the meter leads hooked up to the specific wires, and you get a reading. Now you reverse the meter leads on the same two wires... you should not get a reading.

If you obtain a reading in both directions, or none in both directions, that would indicate the diode is faulty.
 
Yes if the tach is working it means that the stator is almost certain to be OK. I forgot you said that.
 
I understand that your tachometer is operating normally. The gray wire leading from the tachometer back to the terminal board at the engine..... is that gray tachometer wire attached to a yellow wire terminal that leads to the stator OR is it still attached to another gray wire terminal that leads to the voltage regulator/rectifier assembly?
 
That is something important that you need to find out. Trace that yellow/white wire back and find ou what it's attached to.
 
When I got my 1978 powerhead replaced with this one off another motor the Tach wasn't working. I read on this forum that it could be rectifier,so I called the man who sold me the powerhead and ask him was this motor charging. He told me to bring it back and he would check it. He told me it was a loose wire and motor charging system was fine. Well it's not charging but somehow he did get the tach to work.
 
I understand what you're saying BUT you still need to know what that wire is attached to at the engine. If you don't know how to do that, you'll need to ask someone that does.

I strongly suspect that the previous owner simply connected the tachometer to one of the stator's yellow wires, bypassing the rectifier. This would tell me that the voltage regulator/rectifier is faulty (and he knows it), and this would be the reason that the charging system isn't functional.
 
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First of all, thank you for all you do here on forum! Yes, the tach wire is hooked to wire from stator. I trusted this man to at least tell me the truth. I'm no mechanic but I was aware that if tach didn"t work it might not be charging. I had no idea, you could bypass rectifier to get it to work. He told me he had found a loose wire and it was charging.
 
The so called mechanic keeps harping on if I remove ground cable from motor it will stay running and that proves charging system is working. I fit is indead working why is there no change in battery volts running or not ,actually meter shows a little less volts at battery with engine running. By the way where should gray wire be on terminial block? Thanks
 
Like Joe said above...your mechanic is just plain wrong about the battery cable. The engine has an ignition system that generates it's own operating voltages. Once the starter spins that flywheel, the ignition system is powered and functional.
The engine will run without a battery connected at all.

Just change the reg/rect and be done with it. By the way, your part number is wrong for a 1990 150. The part you reference is only used on 1984 150s. You never posted your model number....
 
Do you know what year it actually is? Does it still have the model number plate?
The BIG difference is that the 1984 reg/rect is mounted to the block, and uses a thermal heat compound to transfer heat away from the rect. The 1990 is a water cooled unit, and is mounted into the top of the block where water can remove the heat. So, you see, it is critical that you know what part you need.
 
In addition to Daselbee's above first paragraph on target statement (Post 560), the stator under the flywheel is a two fold component...... there are a series of small coils that pertain to the charging system, and two larger black coils that pertain to the ignition system.

Those two large black coils provide approximately 300 AC volts to the capacitor within the powerpack, needed to energize the powerpack and provide ignition.

The series of smaller coils may be perfectly okay, providing charging power (obvious as it powers your tachomter) BUT if the regulator/rectifier is faulty, that charging power cannot pass thru to the battery.

As far as the engine running with one cable removed (excellent way to damage the charging system)........ Even if no battery was present, and with the key in the ON position, and if one was in a physical condition whereas he/she could crank the engine over fast enough to have the stator energize the powerpack, the engine would start and run. Think about it..... your engine has the same type ignition that the smaller (non battery) models has.... and they start simply by cranking them over via manual start.

All of the above posts/replies spell out Faulty Voltage Regulator/Rectfier. The mechanic that stated "if I remove ground cable from motor it will stay running and that proves charging system is working" needs a refresher course in electronics.
 
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Seems everting points to bad rectifier# 528905. It is on outside on block. I will replace and let you know results. Thanks again for all your help.
 
does this motor have a regulator or is it a rectifier only engine?i am away from all my material at the moment....if its a rectifier only engine and i didnt know how to use a meter i would ask at the parts desk of a local dealer if they could check it...they may know how right at the desk or can step in the shop for someone to do it real quick...it takes about 15 seconds...that rectifier only design aint worth a hoot in todays world with the newer batteries etc...
 
It is part #528905 and list as rectifier/regulator. I have one on order now. I checked it with meter and tested bad. Will post if this part was my problem. Thanks
 
Replaced rectifier/regulator today and boat engine is charging now! Thanks to all who helped me with my problem. It's great to have people like you all that are willing to help us.
 
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