Mercury not producing a charge to battery

[brandon6.0]

I have noticed on the last two trips out that my battery was almost competely drained down. So today i checked the voltage at the battery and had 12volts. So, i started engine and raised rpm to 1500 and didnt see no increase to 14.5 volts only 12volts. So, what could be the problem? Just purchased boat. It has from what i can tell two new CDI rectifiers and new stator assemblie. Have voltage on all red wires to rectifiers. Tach also works. Any help is appreciated thanks guys!

 

[Maxz695]

Re: Mercury not producing a charge to battery

sounds like the rectifier or bad wiring . What HP motor do you have?

 

[Barnacle_Bill]

Re: Mercury not producing a charge to battery

Test your rectifier and regulator if you have one. It really does help to know exactly what motor you have.

 

[brandon6.0]

Re: Mercury not producing a charge to battery

Merc xr6 150 1992yr model.

 

[Chris1956]

Re: Mercury not producing a charge to battery

That motor has twin 20A charging circuits, most likely with voltage regulators. First check is to look at potted area of regulators. Bad ones can have burn marks. Next is to inspect the 4 yellow stator wires, from under the flywheel. If that are intact, test stator wires with motor running on a flusher, and see if you have AC voltage. If so, regulators are likely bad.

You have described new CDI Voltage Regulators, and a working tach. If that is so, the charging system should be working, but you indicate it isn't. Yellow wires are connected to VRs? Red wires are connected to VRs? Grey wire is connected to a VR?

 

[aussieflash]

Re: Mercury not producing a charge to battery

You can do a quick ohm test on Rectifier.Even new ones wont tolerate any wiring mishaps.Especially reversing poles.

 

[brandon6.0]

Re: Mercury not producing a charge to battery

yeah i plan on picking up a ohm meter to test them. All wires are hooked up correctly. First thing i checked out. Read up on inet that a bad VR can still have a good tach signal. I will check them and report back. Thanks guys!

 

[brandon6.0]

Re: Mercury not producing a charge to battery

ok checked with ohm meter and on the top VR i had a pretty good reding almost pegged the meter out. The other one was not reading anything. This was checking the two yellow wires feeding each from stator. With no reading the bottom one is bad correct?

 

[Chris1956]

Re: Mercury not producing a charge to battery

Are you performing a resistance check across the yellow stator wires, or an AC voltage test with the motor running? The Service manual says there should be .25-.45 ohm resistance across the stator leads. So set the meter to Rx1 and test across both short yellow leads and see what you have. Repeat test with long yellow leads. Be sure to dicsonnect stator leads from VRs before testing.

 

[brandon6.0]

Re: Mercury not producing a charge to battery

redone a test just like u stated. I had a reading across all wires tht was the same. Only differece was one of the yellow VR leads shows nothing. Infinty is what i think they call it. All the others seem to match up to the rest of the tests like they should. Does CDI offer any warranties on these?

 

[Faztbullet]

Re: Mercury not producing a charge to battery

From CDI to check rect/regulator:
Diode plate check: Test the forward diodes between the two yellow wires and the red wire. You should get a reading of
about 45K (45,000) on one and a high reading on the other. Check the resistance from each of the yellow wires to case ground, you should get a reading of about 56K (56,000) on one and a high reading on the other. The red wire should read about 14K (14,000) ohms to ground.
Tachometer Circuit:
Check the resistance between the gray wire and engine ground. You should read above 100K (100,000) ohms. Gray to red, and gray to the yellow wires should be a high reading, usually in the M range

 

[brandon6.0]

Re: Mercury not producing a charge to battery

Ok that helps alot.

Thanks for your support!