Mercury Rectifier/Regulator Info

[sportyinc]

Hello,
A month or two ago "Sticky" posted a notice about and a link to an aftermarket rectifier/regulator. I believe the unit was designed for large lawnmower engines (Onan?, John Deere?)

If anyone had better foresight than me to actually bookmark the site or the post, I would appreciate the info.

Thanks

 

[usskydvr]

Re: Mercury Rectifier/Regulator Info

So are you talking about a rectifier? If so just go to Radio Shack and get a 25A or 35A full wave bridge rectifier. If you are talking about a rectifier/regulator single unit then they were talking about a
Kohler p/n KH4309 15A, 14.4 V

 

[sportyinc]

Re: Mercury Rectifier/Regulator Info

Thanks, that looks like the numbers I saw.
I purchased the Radio Shack rectifier and it works great. Only 1 problem. The output voltage reads 17 Volts.
I bought one of the Kohler KH3409, hooked two yellows to the 2 "AC" and Red from harness to B+. I grounded the Rectifier with a wire from the mounting bolt to the engine. Started the engine, NO TACH. Put the Radio Shack back on, Works Great (still high Volt).
Maybe i got a bad KH3409? Any way to test it?

Again, thanks for the info.

 

[usskydvr]

Re: Mercury Rectifier/Regulator Info

What engine are we talking about? You may be able to pick up the tach pulses elsewhere. Keep in mind the rectifier only changes the AC to DC, no regulation and very 'dirty' DC at that. The rectifier/regulator not only changes from AC to DC but ALSO regulates the voltage. In doing so you lose the tach pulses.

 

[sportyinc]

Re: Mercury Rectifier/Regulator Info

I did not know that. So where do tachometers on engines with regulators get their signal?
Since the tach gets the signal from the stator BEFORE the rectifier, it seems strange the tach wouldn't work connected to the stator Before the regulator.
Would using a seperate rectifier and regulator work?

I've got a '72 Mercury 1150. Stock they do not have a regulator but I spent $600 on a Chart Plotter and I don't feel good about pumping 17 Volts into it.

 

[usskydvr]

Re: Mercury Rectifier/Regulator Info

Some engines get it from the coil. Some from the AC stator signel. Your engine has Thunderbold CDI switchbox ignition. Your tach signal is the Brown terminal on the switch box with four terminals on it.
Green, to the coil
Brown, to the tach
Red, to the harness and also to the Rectifier (now rectifier/regulator)
White, to the harness

 

[sportyinc]

Re: Mercury Rectifier/Regulator Info

That is good news!
The Brown wire on the switch box is the one going to the distributor and also has the tilt switch connected.

I will try hooking the tach to the Brown wire and see what happens. That way I will be able to use a rectifier/regulator.

Do I keep the tach pole setting at "6"?

 

[usskydvr]

Re: Mercury Rectifier/Regulator Info

Hold on a minute. The Brown wire going to the distribotor is not the correct one. I already gave the wires on one side of the switchbox. Here are the ones for the other side.
Black, to the Dist
White , to the Dist
Brown, to the Dist and also to the Mercury switch (used to kill the engine when it is tilted up)

 

[sportyinc]

Re: Mercury Rectifier/Regulator Info

You are absolutely right. I have a wiring diagram in front of me but I failed to see that there is a Brown wire on BOTH sides. Guess I wasn't paying attention.

One side of the Switch Box has 4 wires, the other side 3.
On the side with 4 terminals, I show green, brown, red and white wires, starting at the top. Your diagram is the same EXCEPT yours shows the top wire going to the coil is Black. Mine shows it as green.

Anyway, the brown on the side with 4 terminals is the brown I use. This wire goes through the wiring harness to the tach connector on the remote control.
Thanks for keeping me focused.

 

[usskydvr]

Re: Mercury Rectifier/Regulator Info

Correct. Some diagrams I have seen show the top wire as Black (like this one) , some show green (as I originally identified in my earlier note). Either way you are good to go now.

 

[chris115mariner]

Re: Mercury Rectifier/Regulator Info

hey not to get off subject but i'm have problems and I wanted to know at night I do not see any fire jumping but I can pull the wires off the plugs and fire starts jumping where the wire goes in to the coil pack and even the wire its self my motor has no power under load and shakes and jumps and souds bad but like I said if the wires are on the plug they dont arch but pull one off and its achs pull two they both arch and so on

 

[usskydvr]

Re: Mercury Rectifier/Regulator Info

Chris, you need new plug wires. when you pull the wires off the plugs it causes additional load which in turn causes the spark to look for the path of least resistance. The arcing by the coil indicates bad plug wires.