Possible Alternator Problem?
 

Hi All,

I own a 1970 Starcraft Holiday V boat with a 120 hp I/O. I recently
took into the shop to get dewinterized, have the oil changed and even
check into what appeared to be an idling problem that I had had
before. When I rode the boat this weekend, the boat ran well right up
to the point we were able to get into an area where we were able to
open up the throttle and get some good speed. Upon throttling down to
we noticed the engine began to sputter and then die. When we
attempted to start it back up again, we got the typical clicking sound
a car makes when its battery is dead. I looked at the battery, but
the connections seemed to be good.

I recently had a fish finder put in and it has a volt meter built into
the display. The voltage off the battery was somewhere around 7.5
volts. We had a vessel assist boat give us a jump and the boat
started right back up again - the voltage on the fish finders volt
meter then read 12.8 volts. (If we turned on nav light, blower,
bilge, and horn, the voltage dropped confirming that at least it was
reading what we thought it was based on the fact that the voltage
dropped and rose again when we first turned them all on and then off.

When we took the jumper cables off, the boat still ran, but as soon as
we kicked it into gear and began to motor away, the engine began to
faulter and then die only to not restart (making the clicking sound)
it originally did.

Does this sound like an alternator issue to anyone? Could it be
related to any other type of electrical issue?

Many thanks for any input!

Sean

Possible Alternator Problem?
 

First off, the ignition system, even if points, will not work at that
low voltage. If electronic, not below 10.6V. If the alternator is not
charging, getting a jump will do absolutely nothing, for as soon as the
teeny little boost the jump provided is gone, it will just shut off
again. If the voltage did not rise immediately on start to at least
+13V, the charging system is not working.
JR

Jolly Roger wrote:

Hi All,

I own a 1970 Starcraft Holiday V boat with a 120 hp I/O. I recently
took into the shop to get dewinterized, have the oil changed and even
check into what appeared to be an idling problem that I had had
before. When I rode the boat this weekend, the boat ran well right up
to the point we were able to get into an area where we were able to
open up the throttle and get some good speed. Upon throttling down to
we noticed the engine began to sputter and then die. When we
attempted to start it back up again, we got the typical clicking sound
a car makes when its battery is dead. I looked at the battery, but
the connections seemed to be good.

I recently had a fish finder put in and it has a volt meter built into
the display. The voltage off the battery was somewhere around 7.5
volts. We had a vessel assist boat give us a jump and the boat
started right back up again - the voltage on the fish finders volt
meter then read 12.8 volts. (If we turned on nav light, blower,
bilge, and horn, the voltage dropped confirming that at least it was
reading what we thought it was based on the fact that the voltage
dropped and rose again when we first turned them all on and then off.

When we took the jumper cables off, the boat still ran, but as soon as
we kicked it into gear and began to motor away, the engine began to
faulter and then die only to not restart (making the clicking sound)
it originally did.

Does this sound like an alternator issue to anyone? Could it be
related to any other type of electrical issue?

Many thanks for any input!

Sean



--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth

Possible Alternator Problem?
 

On Thu, 05 Jul 2007 16:31:17 -0700, JR North
wrote:

If the voltage did not rise immediately on start to at least
+13V, the charging system is not working.

Most likely the alternator/voltage regulator, usually the same unit
these days. Many NAPA auto parts stores can test it for you,
otherwise find a good local alternator shop. Most alternators can be
rebuilt for a reasonable price.

Possible Alternator Problem?
 

On Jul 5, 9:12 pm, wrote:

Most likely the alternator/voltage regulator, usually the same unit
these days. Many NAPA auto parts stores can test it for you,
otherwise find a good local alternator shop. Most alternators can be
rebuilt for a reasonable price.

Just be sure the alternator guy understands this is a marine
alternator and you need all those funnyy screens he has never seen
before. Make sure he puts them all back. Other than that it is a
regular alternator.

Er, almost. a 1970 model. Mercruiser? OMC?

Anyhow, look for a blown fuse first. then....

If OMC, it probably has an ancient Prestolite, which is way difficult
to get parts for, but usually don't go bad no matter how many hr.s are
on them, that is, unless the berings get rattly. Either that or if
Mercruiser, it probably has an old 10 DN Delco (seperate VR). or maybe
even a Motorcraft (Ford)

These alternators (if external regulated) is easy to test. Make sure
you have a good quality connection to the output stud on the back of
the alternator (Usually 10 guage wire) It should be hot full time. It
"usually"connects directly to the battery cable at the starter
solonoid.

Make sure you have good current there. and the nut isn't corroded.
Either alternator, disconnect the "field" , or "brush" wire. It should
be marked with an "F" or "Fld" right on the alternator housing. then
when running, use a jumper wire to the Battery Pos. and to the "Field"
terminal, thus by-passing the volt reg. with a volt meter, the voltage
should start to climb 15- up to 17 volts on the guage. That is if the
alternator is working correctly. It it is? then Volt reg. time, or
look for rusty connections and corrosion. clean
terminals,connections, rusty mount etc. ... plug fld wire back on
alternator and try again. If no go, replace the VR.

If internal VR, it's probably a Delco 10 SI but they didn't start
using those till after 1973 or 75, I can't remember, but it's
doubtful it would have one of those unless it's been retrofitted.
Prestolite, (OMC) started mounting a VR directly to the back of their
units in about 1975

Thats really basic, Unless I know what you have I can't do much more.

Possible Alternator Problem?
 

Hey thanks all - After some investigation - it was found that the
alternator & voltage regulator in this boat (made 37 yrs ago) are two
separate components. The most interesting part is that after having
the alternator tested by the mechanic and having it check out okay!
We ended up testing the voltage regulator and low and behold it was no
longer working - 37 yrs on the job wasn't too bad.

Anyway - just wanted to let you all know what the resolution was.


On Jul 5, 7:32 pm, Tim wrote:
On Jul 5, 9:12 pm, wrote:

Most likely thealternator/voltage regulator, usually the same unit
these days. Many NAPA auto parts stores can test it for you,
otherwise find a good localalternatorshop. Most alternators can be
rebuilt for a reasonable price.

Just be sure thealternatorguy understands this is a marine
alternatorand you need all those funnyy screens he has never seen
before. Make sure he puts them all back. Other than that it is a
regularalternator.

Er, almost. a 1970 model. Mercruiser? OMC?

Anyhow, look for a blown fuse first. then....

If OMC, it probably has an ancient Prestolite, which is way difficult
to get parts for, but usually don't go bad no matter how many hr.s are
on them, that is, unless the berings get rattly. Either that or if
Mercruiser, it probably has an old 10 DN Delco (seperate VR). or maybe
even a Motorcraft (Ford)

These alternators (if external regulated) is easy to test. Make sure
you have a good quality connection to the output stud on the back of
thealternator(Usually 10 guage wire) It should be hot full time. It
"usually"connects directly to the battery cable at the starter
solonoid.

Make sure you have good current there. and the nut isn't corroded.
Eitheralternator, disconnect the "field" , or "brush" wire. It should
be marked with an "F" or "Fld" right on thealternatorhousing. then
when running, use a jumper wire to the Battery Pos. and to the "Field"
terminal, thus by-passing the volt reg. with a volt meter, the voltage
should start to climb 15- up to 17 volts on the guage. That is if thealternatoris working correctly. It it is? then Volt reg. time, or
look for rusty connections and corrosion. clean
terminals,connections, rusty mount etc. ... plug fld wire back onalternatorand try again. If no go, replace the VR.

If internal VR, it's probably a Delco 10 SI but they didn't start
using those till after 1973 or 75, I can't remember, but it's
doubtful it would have one of those unless it's been retrofitted.
Prestolite, (OMC) started mounting a VR directly to the back of their
units in about 1975

Thats really basic, Unless I know what you have I can't do much more.

Possible Alternator Problem?
 

On Jul 16, 3:15 pm, Jolly Roger wrote:
Hey thanks all - After some investigation - it was found that the
alternator & voltage regulator in this boat (made 37 yrs ago) are two
separate components. The most interesting part is that after having
the alternator tested by the mechanic and having it check out okay!
We ended up testing the voltage regulator and low and behold it was no
longer working - 37 yrs on the job wasn't too bad.

Anyway - just wanted to let you all know what the resolution was.

On Jul 5, 7:32 pm, Tim wrote:



On Jul 5, 9:12 pm, wrote:

Most likely thealternator/voltage regulator, usually the same unit
these days. Many NAPA auto parts stores can test it for you,
otherwise find a good localalternatorshop. Most alternators can be
rebuilt for a reasonable price.

Just be sure thealternatorguy understands this is a marine
alternatorand you need all those funnyy screens he has never seen
before. Make sure he puts them all back. Other than that it is a
regularalternator.

Er, almost. a 1970 model. Mercruiser? OMC?

Anyhow, look for a blown fuse first. then....

If OMC, it probably has an ancient Prestolite, which is way difficult
to get parts for, but usually don't go bad no matter how many hr.s are
on them, that is, unless the berings get rattly. Either that or if
Mercruiser, it probably has an old 10 DN Delco (seperate VR). or maybe
even a Motorcraft (Ford)

These alternators (if external regulated) is easy to test. Make sure
you have a good quality connection to the output stud on the back of
thealternator(Usually 10 guage wire) It should be hot full time. It
"usually"connects directly to the battery cable at the starter
solonoid.

Make sure you have good current there. and the nut isn't corroded.
Eitheralternator, disconnect the "field" , or "brush" wire. It should
be marked with an "F" or "Fld" right on thealternatorhousing. then
when running, use a jumper wire to the Battery Pos. and to the "Field"
terminal, thus by-passing the volt reg. with a volt meter, the voltage
should start to climb 15- up to 17 volts on the guage. That is if thealternatoris working correctly. It it is? then Volt reg. time, or
look for rusty connections and corrosion. clean
terminals,connections, rusty mount etc. ... plug fld wire back onalternatorand try again. If no go, replace the VR.

If internal VR, it's probably a Delco 10 SI but they didn't start
using those till after 1973 or 75, I can't remember, but it's
doubtful it would have one of those unless it's been retrofitted.
Prestolite, (OMC) started mounting a VR directly to the back of their
units in about 1975

Thats really basic, Unless I know what you have I can't do much more.- Hide quoted text -

- Show quoted text -

Cool!