87' 165 mercriuser stator & regulator problems

[leehoenig]

I have replaced both the stator and regulator and i am still getting an over charge problem. the regulator starts to get very hot and begins to smoke within a minute of running time. the cooling system seems to be working fine.any info would be appreciated.

 

[denniz]

Re: 87' 165 mercriuser stator & regulator problems

Guess you got a 165 4cyl. Have you checked into the bolt on alt kits available for that engine? Its cheaper in the long run.

 

[dick]

Re: 87' 165 mercriuser stator & regulator problems

Check the battery or batteries a bad battery can cause havok. When you replaced the reg... was it not charging or over-charging ?

 

[leehoenig]

Re: 87' 165 mercriuser stator & regulator problems

Thanks for the responses.yes i know about the alternator kit and that it is what i should have done but didn't and now have spent $600.00 on these parts. Let me add some info. the serial# B525770 4cyl 165 mercruiser 1987. last year the regulator caught on fire and burned the wire harness. I replaced the damaged wires and installed a new reg. The boat ran great took the kids sking for hrs. We used the boat 4-5 more times and on the last trip in i smelled burning wires again.I tested the reg and stator again, the stator tested at 1.1ohm of resistance .1 more than the book indicated . so i replaced the stator. Started the engine and 15-30 seconds later smoke from the reg spews again. I've checked the battery it has plenty of power but is sealed and can not test the cells individually. i also disconnected all wires and cleaned the cotact surfaces. now im lost.....

 

[dick]

Re: 87' 165 mercriuser stator & regulator problems

Sounds like you got a short to ground somewhere, now the fun part is finding it.Start tracing the wires on the engine and make sure nothing is worn through or contacting another terminal ,particually around the stator and regulator area .Hope you didn't fry your new parts.

 

[leehoenig]

Re: 87' 165 mercriuser stator & regulator problems

Ohboy, fun with wires 101. do you think that the short to ground would show it self with a circut tester? I found a pinched wire that goes to my outdrive pump,no cuts and it works fine. Should i replace the wire? any input is always welcome and appreciated

 

[MrBill]

Re: 87' 165 mercriuser stator & regulator problems

lee....<br />I have the same set up, direct drive alternator charging system. The stator produces alternating current and a remote diode changes the alternating current to direct current. A water-cooled voltage regulator is used with this system, and as you probably know it's expensive. The $30 I spent on the Clymer Mercruiser Shop Manual has proved invaluable. Back to your problem...........<br /><br />There are several diagnostic tests which can be performed, but two most notably...the high output test and the resistance test.<br /><br />First (High Output)- disconnect neg battery cable, connect tach to engine according to the equipment instructions. Disconnect orange wire at regulator and connect an ammeter between the wire and its terminal, reconnect battery cable. Then disconnect one of the yellow/red wires at the regulator and tape end out of the way to prevent short. Start engine and run at 1000 RPM. The ammeter should show NO OUTPUT. If it does, there is a stator short (to ground). Reconnect the yellow/red wire and repeat with the other yellow/red. If there is no output, regulator could be the problem.<br /><br />Second (resistance test) - Disconnect both yellow/red wires and the orange wire at the regulator. Check resistance between the regulator case and the yellow/red wire regulator studs with an ohm meter. If a near zero resistance reading is obtained, regulator is a problem. Next, check the resistance bet2ween the two yellow/red wires - if resistance is greater than 1 ohm, the stator is problematic. (this test is easiest since engine does not need to be running).<br /><br />Lastly, reconnect all regulator leads and disconnect the fourth (red/purple sensing)wire. Connect ammeter between this wire and the regulator stud, start engine, run at 1000 rpm. If there is any current regulator is a problem.<br /><br />There are additional tests but my manual is not here to reference, hope that atleast some of this is helpful.

 

[leehoenig]

Re: 87' 165 mercriuser stator & regulator problems

Mr Bill thanks for your help, I have the same manual but I am no mechanic.A good friend of mine works on very large diesel engines and he is not totaly sure what to do next. we have already performed all the tests you suggested and replaced the stator and reglator. the problem still exists. Where would i find this remote diode on my boat? on the engine or under dash? I've read about it in my book but cant find it.the thing must be really remote any more help would be greatly appreaciated.

 

[MrBill]

Re: 87' 165 mercriuser stator & regulator problems

Unfortunately I am not able to take a first hand look since my boat is up at the lake 100 miles away, and it'll be two weeks before I return, but here's my recollection.<br /><br />Looking at the engine from the port side...starter is to the right. Left of the starter is the slave solenoid, and to the left of the solenoid is the remote diode rectifier. My appologies for not properly indicating the full name of this part, I left out the word 'rectifier' in error in my first reply. Hope this helps....