3.7 470 conversation of votage reg

[Richard11153]

I want to convert my merc 3.7 for use with an alt.
Do I have to remove the old stater (under / in, the engine balancer)
I know I can leave the old Voltage Reg in place.
Also, is there a diff if a use a one wire alt, or 3 wire alt. I see both are available.
(I still want my dash voltage guage to work)

Any help?

Thank / Richard

 

[Eric 3.7LX Alpha 1]

Re: 3.7 470 conversation of votage reg

You don't have to remove the stator, I did and sold it on ebay. disconnect the yellow/red wires and cap em if you keep it on.

The voltage gauge will work with both alternators,

Check here for the conversion kit:
breezeworks.net

they have a low and high mount depending if you have power steering or not.

 

[Richard11153]

Re: 3.7 470 conversation of votage reg

so why are 1 wire, and some or 3 wire, connections.
(whats the diff? Is one better than the other?)

 

[Eric 3.7LX Alpha 1]

Re: 3.7 470 conversation of votage reg

Read this article between the two:
http://www.madelectrical.com/electricaltech/onewire-threewire.shtml

I have the 3-wire, the only advantage of the one wire is it's faster to install, but not necessarily better.

 

[stonyloam]

Re: 3.7 470 conversation of votage reg

You can remove all of the wires from the voltage regulator (both ends).

 

[a1nowell]

Re: 3.7 470 conversation of votage reg

Richard,
I believe a 1 wire altenator will not start charging until around 1200to 1500 rpm. The 3 wire starts charging at any rpm. That is my understanding of the basic difference between the 1 wire vs the3 wire systems. I believe breezeworks conversion kits are only 3 wire.

Advantages
Disadvantages

3-Wire Alternator
Ignition warning light works as designed.
Field windings turn on with ignition switch (no cut-in required).
Much better voltage regulation at the main terminal power post.
Inexpensive and plentiful.

A little more complicated to wire up.

1-Wire Alternator
Installation is simplified and provides for a very clean setup.
Regulated voltage monitored at alternator; low voltage conditions may occur at main terminal power post.
The ignition warning light is omitted
Throttle must be blipped 1200-2000 RPM at startup to force it to cut-in.
More expensive to buy.

 

[alan ber]

Re: 3.7 470 conversation of votage reg

Hello Richard
I did the same conversion
I have a local alternator/ starter rebuild shop that is open too public
I have the merc 4 cylinder, ford engine
Shop had a number of rebuilt marine alternators.
Had a number of steel brackets various sizes.
On my engine at lower area where the water over flow container was mounted is two threds. I used one for support.
I happened too have a long curved piece of steel simuliar too a boomarang, that supported alternator and mounted off one of the bolts on power steering bolts.
Used string, measured and took too auto zone for a match. Got a size slightly smaller, and still with adjustments had too make
a number of trips finding the proper size.
My cost was 125.00 alternator
12.00 belt
Single wire, have its own in line fuse just in case, and it goes too starter
Works fine, takes a while for gauge too register, but works fine and lot better then original system.
Bottom line , bracket is the issue, and once done, secure, changing of a hundred dollar alternator beats old stator
system especially new is new old, expensive and used on ebay is risky.
Good luck

 

[Richard11153]

Re: 3.7 470 conversation of votage reg

Not sure what you meant by this....
"Single wire, have its own in line fuse just in case, and it goes too starter"

In line fuse is "waht amp"? Why would the wire do to the starter?

Thanks

 

[Eric 3.7LX Alpha 1]

Re: 3.7 470 conversation of votage reg

He has the "output" terminal of the alternator connected to the large terminal of the starter that the "red" positive cable from the battery runs to. The starter is connecting the alternator to the battery thru that terminal.

 

[alan ber]

Re: 3.7 470 conversation of votage reg

Originally I ran directly too battery, Can't remember what caused wire too ground out, but when this happened the smoke
from burning wires looked as if my entire wiring harness was burning.
When I inspected damage it was only the wire going from alternator
When I wired originally it went from alternator too a breaker bar, then the other side of bar went too battery. simuliar too a fuse.
Some say wire directly too starter or battery, makes no difference.
Old regulator system had a ( I think it's a ) 30 amp fuse off the starter. Fuse was good and just wired too it and the other end connected too starter. Battery cable goes too battery this way alternator line is protected and juice goes too battery
As I said earlier finding a system that supports the alternator is key.
I did not adjust belt tension off of alternator I used the adjustment off of the power steering pump. On my 4 cylinder
mercruiser pump can tighten or loosen by the two bolts directly behind pump that goes too engine.

 

[Richard11153]

Re: 3.7 470 conversation of votage reg

So, Just to understand, If I get a 1 wire alt, My guage on the dash will still work. Correct?
Also, with the 1 wire system, (i'm leaning that way), It dosent "kick in" untill you rev the engine to say 1500 rpm,
but then it starts charging, even at low RPMs. Correct?

Thanks in advance!!!!

 

[H.E.mech01]

Re: 3.7 470 conversation of votage reg

I also recently converted my 3.7l merc from the origional stator to a 1 wire delco. I bought the alternator from ebay for 66.00$ and made my own brackets as I have welding and fabrication experience. all I did was disconnect the stator wires and taped them up and disconnected the wire that went from the voltage regulator to the the large starter terminal wich is battery +. I ran a 10ga automotive wire that I purchased from autozone around the back od the engine along with the existing wireing harness. My gauge on the dash is a voltmeter as most are and it shows 14.5 volts at idle. meaning that it is charging. If you have an amp gauge on your dash it might not work but I doubt that you have an amp gauge. Mine works awesome. I drove the boat to NAPA and used a tape measure to get close to the correct size belt so I didnt have to make multiple trips to town. after the third belt I got the right one NAPA didnt make me purchase one till I got the right one. I hope my experience helped in some way. But I love the one wire you just have to hook up a wire from alt to bat+ and it charges.

 

[Richard11153]

Re: 3.7 470 conversation of votage reg

I have a volt guage.
Thanks a lot!

 

[Eric 3.7LX Alpha 1]

Re: 3.7 470 conversation of votage reg

Yes the volts gauge will work with both types of alternators.

 

[structural1]

Re: 3.7 470 conversation of votage reg

He has the "output" terminal of the alternator connected to the large terminal of the starter that the "red" positive cable from the battery runs to. The starter is connecting the alternator to the battery thru that terminal.

Hey Eric.... Silly question and I apologize. But is this a diagram for a 3 wire Alternator? Seems like it is since it has 3 wires coming out of it...