1996 SeaRay 215 Express Cruiser electrical issue

[Ed Harris]

For the past 3 years boat has been running flawlessly with no issues. Then this problem appeared.
1996 mercruiser 5.7L in a SeaRay 215 EC
When the key is turned on the volt gauge reads 11 but battery reads 12.5 with voltmeter
Engine cranks and runs smooth but the volt gauge drops to 9.5 or 10 but if you give it some throttle it will creep up to 12.5 running. As i turn on the blower, stereo, lights, bilge pump the volt meter will drop to 10 or 11 volts and the engine just shuts off. It shut off like you turn the key off. No spitting or sputtering like a fuel issue.
Batteries have checked as good. There is no oil pressure switch as it was removed when i bought the boat. As earlier the engine has been running good for 3 years.
Alternator has been rebuilt with Mondo parts from a reputable starter and alternator rebuilder. The orange wire from the alternator is reading 15v with engine running. I had the alternator rebuilt because i thought it was going bad because this problem started before i had the alternator rebuilt.
Water temp is 160. Oil pressure is 40 #s at idle.
It will crank right up after you turn the key off and back to restart.
I tried a new key switch today but that didnt help.
Where should I start with this Thunderbolt ignition?


All reactions:
22

 

[dubs283]

Sounds like a connection issue, most likely corrosion on one or more positive or ground connections.

Have you performed a voltage drop test on any circuits?

 

[Scott Danforth]

start at the battery and clean every connection to the motor and up the wiring harness to the helm.

by clean, I mean clean enough your mother in law would eat off them.

then when completed, seal them with marine electrical varnish

 

[Ed Harris]

Sounds like a connection issue, most likely corrosion on one or more positive or ground connections.

Have you performed a voltage drop test on any circuits?

I have not performed any voltage drop test other than watching the voltage drop on my dash gauge when I turn on stereo, blower, bilge, lights etc...

 

[flashback]

just start cleaning the connections, I have a 95 SR and I found the buss bar terminals for ground wires needed it badly..It's a good pastime when you feel like tinkering...

 

[Ed Harris]

just start cleaning the connections, I have a 95 SR and I found the buss bar terminals for ground wires needed it badly..It's a good pastime when you feel like tinkering...

I will give all that a try when i get a chance and will report back. It may be next week but i will report back.

 

[mr 88]

Have you verified the voltage meter accuracy itself or checked the voltage going into it at the back of the meter . If that checks out backtrack each connection and use your multimeter to find the voltage drop .

 

[tank1949]

For the past 3 years boat has been running flawlessly with no issues. Then this problem appeared.
1996 mercruiser 5.7L in a SeaRay 215 EC
When the key is turned on the volt gauge reads 11 but battery reads 12.5 with voltmeter
Engine cranks and runs smooth but the volt gauge drops to 9.5 or 10 but if you give it some throttle it will creep up to 12.5 running. As i turn on the blower, stereo, lights, bilge pump the volt meter will drop to 10 or 11 volts and the engine just shuts off. It shut off like you turn the key off. No spitting or sputtering like a fuel issue.
Batteries have checked as good. There is no oil pressure switch as it was removed when i bought the boat. As earlier the engine has been running good for 3 years.
Alternator has been rebuilt with Mondo parts from a reputable starter and alternator rebuilder. The orange wire from the alternator is reading 15v with engine running. I had the alternator rebuilt because i thought it was going bad because this problem started before i had the alternator rebuilt.
Water temp is 160. Oil pressure is 40 #s at idle.
It will crank right up after you turn the key off and back to restart.
I tried a new key switch today but that didnt help.
Where should I start with this Thunderbolt ignition?


All reactions:
22

u have corrosion somewhere. Look for green crap. Start at battery. Make sure battery is in good cond and fully charged.

 

[Ed Harris]

Update:
All connections are good. All the ignition wiring has continuity. Starter and solenoid all checks good. Ford type Solenoid on top of motor checks as good.
Older mechanic told me to replace the belt for the alternator
Belt is ordered and on the way. Will post back results.

 

[04fxdwgi25]

Alternator belt or alternator itself, possibly.

Do the voltage checks at battery when running. Should be a min of 13.8V when on fast idle and under load. If it is good, then back to the connections checks.

Was belt loose / squealing?

 

[dubs283]

All the ignition wiring has continuity. Starter and solenoid all checks good. Ford type Solenoid on top of motor checks as good.

Items mentioned here don't have a direct correlation with the charging system. Great they are all sound but even if any of the above mentioned components/systems had a failure it most likely would not affect the charging system

Older mechanic told me to replace the belt for the alternator

Posted info earlier mentioned 15 volts running at alternator output. This is a sound reading. Replacing the belt should not change anything. Your issue lies in between the alternator output and the battery

 

[Ed Harris]

Update:
Slave solenoid was bad. Picked up a Sierra from West M.
Voltage at slave sol. Is 12v when turning the key to start it drops to 8V on the ignition wire. What should the purple yellow stripe wire at the alternator read when the engine is running? I am reading like 8V.

 

[Scott Danforth]

Clean all connections in the boat

 

[Ed Harris]

Alternator was only putting out 12V while engine was running during all these checks
Could the circuit breaker be faulty? Somewhere the ignition is noticing the low voltage and is shutting the engine down just like you would turn the key off.

 

[nola mike]

Alternator was only putting out 12V while engine was running during all these checks
Could the circuit breaker be faulty? Somewhere the ignition is noticing the low voltage and is shutting the engine down just like you would turn the key off.

Doesn't sound like you actually did a voltage drop test. Continuity doesn't cut it. How are you measuring alt output? What's the reading at the battery with motor running? My money is bad helm connections. Your volt meter isn't getting full voltage, so neither is purple wire feeding your ignition.. Circuit breaker isn't faulty, solenoid isn't faulty. Bad alternator will allow the boat to run fine until battery discharges. You have a bad connection somewhere.

What should the purple yellow stripe wire at the alternator read when the engine is running? I am reading like 8V.

Didn't see where you posted any specifics of your engine, but I don't believe that wire exists in the wild...

 

[Bondo]

Clean all connections in the boat

Ayuh,..... Includin' the grounds,.....

 

[dubs283]

You're all over the place here. First post says alt output is 15v engine running, now it's 12v? Also, you said the slave solenoid was good, but then it tested bad?

It's fine you're testing and replacing components of the starting and ignition system but those systems have little/nothing to do with the charging system.

Pur/yel wire from alternator is for the electric choke/ignition bypass during starting. You need to start with a voltage check at the alternator output (orange) wire and check every connection between the alternator and the battery including all ground connections. Guessing there is a 90 amp fuse at the starter, these can be problematic.

You say all connections are good but no mention of removing, inpecting, cleaning and ensuring a solid connection.

FYI, watching the volt guage on the dash slowly give a lower reading does not constitute a voltage drop test

 

[nola mike]

Pur/yel wire from alternator is for the electric choke/ignition bypass during starting.

From Alternator or starter?

 

[Ed Harris]

From Alternator or starter?

1996 sea Ray 215ec…5.7L 2 Barrel TBolt IV…….From alternator. I am cleaning all connections as I test them.
That purple yellow stripe wire does go to the choke on my carb.
I do not have a 90 amp fuse at the starter….. only the 50 amp circuit breaker on the manifold.
I know I mentioned the 15V while running but now it is on 12V

 

[nola mike]

1996 sea Ray 215ec…5.7L 2 Barrel TBolt IV…….From alternator. I am cleaning all connections as I test them.
That purple yellow stripe wire does go to the choke on my carb.

Still not seeing that wire anywhere but on the starter. Here's the diagram from service manual #24, which I think is yours. If that wire goes to the alt, you'd essentially be bypassing your oil pressure switch and your fuel pump would be running with the engine off. Someone correct me if I'm wrong...
If you are indeed getting only 12v off the alternator when running (measuring orange wire and ground), then your alternator isn't working...and you'd get battery voltage which would be more than 12v normally. And it would be the same reading with the engine on or off.