1968 Mercruiser (Penn Yan) alternator or regulator problem?

[Scott06]

If there is no alternator output I suspect the alternator. It's been a few years, but On my grandfathers 1966 pen yan (150hp mercruiser) the voltage regulator was on the port side of the upper transom. Approx 4" X 4" square finned box with a multi pin harness connector into the bottom. When the alternator died I was able to convert to a modern internally regulated alternator I think by hooking up the positive wire to the alternator, taping back the other two wires on the engine harness. Voltage reg was disconnected and plug taped off. Worked perfect.

I miss that boat, caught a lot if lake trout in it...

 

[AKPilotnboatman]

Hello. I am not getting a charge on my battery when the battery is running, and I am not sure if it the alternator or the voltage regulator. If it is the regulator, I am unsure where it is or if it even has one??? Just checked with a voltage meter and did not show a charge on the alternator terminals. may be a false reading, as I do remember seeing a charge last time. Any thoughts on the system? Thanks

 

[Bt Doctur]

post a pic of the alt, how many wires does it have?

 

[AKPilotnboatman]

Hmmm. let me figure out how to post pictures again... It has a red wire, black wire, green wire that looks like it touches the black wire...

 

[AKPilotnboatman]

I'll work on the pic

 

[achris]

Doesn't matter, alternator or regulator. External regulator alternators and their regulators haven't been available for many many years. All you can do is pull both out and replace with an internal regulator alternator.

Chris....

 

[AKPilotnboatman]

So if it is the alternator or generator, and it is bad, how would one eliminate the regulator. There ar a lot of wires down there and they are all old and dirty with age... Way too ,Amy wires rally. Will post picture later

 

[Scott06]

See post number 2 outline how to do exactly that

 

[AKPilotnboatman]

By "taping back" the wires, is that just taping them (eliminating them?)

 

[achris]

Taping to insulate against them touching anything they shouldn't. I remember about 2 years ago someone else was here with the same issue, how to remove a external reg and alternator and install an internally regulated alternator. Same engine too. I did a long screed and wiring diagrams. A search may find it for you.

Chris.......

 

[achris]

I searched and found the thread.... However, in readng through I now remember this thread was bomdarded by a troll, and he was trying to take the subject in a different path. I have found the posts relevant to your situation, which are:

http://forums.iboats.com/forum/engin...21#post6596721
and
http://forums.iboats.com/forum/engin...09#post6596809
and
http://forums.iboats.com/forum/engin...45#post6596845

Just remember, if you read the whole thread, it's messy.

If you need a modified diagram, let me know and I'll set one up.

Chris........

 

[Scott06]

If I recall correctly there were 3 wires going to original alternator, hooked orange up to new alt + terminal, others were folder back over harness and wrapped with electrical tape to adequately insulate them. Voltage regulator I simply disconnected at harness plug and covered plug with tape as well.

This was over 20 years ago, can you confirm qty and color of wires to your existing alternator? Did you locate your voltage reg?

 

[achris]

If I recall correctly there were 3 wires going to original alternator,

By the Merc manual (for engines in 1968) they would have been Red/white (alternator output), blue (regulator input) and black (ground).

hooked orange up to new alt + terminal,

Orange output wire from the alternator didn't start until the late 70's. (BIA Colour codes)

others were folder back over harness and wrapped with electrical tape to adequately insulate them. Voltage regulator I simply disconnected at harness plug and covered plug with tape as well.

This was over 20 years ago, can you confirm qty and color of wires to your existing alternator? Did you locate your voltage reg?

 

[Scott06]

chris thanks for clarifying it was years and beers ago... Figure out which is on alternator output, put it on the new one, and it will work.

 

[AKPilotnboatman]

Any idea what alternator to replace with then? I have no part numbers to reference

 

[Scott06]

Good question... I had taken mine to a local alternator shop and he matched it up with a modern marine internally regulated.