Go Back   Maxum Boat Owners Club - Forum > Maxum General > Engines
Click Here to Login
Register FAQ Community Calendar Today's Posts Log in

Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-11-2022, 06:43 AM   #1
rwc
Lt. Commander
 
Join Date: Sep 2017
Location: Vancouver, Canada
Posts: 102
Default No ignition

Hi,

I have a newish 5.7L mercruiser MPI

A few weeks ago, I started the boat up to go out, then it choked and died. Started again, ran for thirty seconds then died. Third time, nothing at all ( no tone, didn’t turn over, just silent). I traced it to the 50A breaker on top of the engine, which had popped.

I pushed the breaker back in and tried it again. It made a funny noise, like a bad connection, then turned over and started, but again died after 10-15 seconds.

So today I cleaned up all the connections between the battery and the starter, reconnected the battery, tried to fire it up and got nothing, breaker is in, but no tone or turn.

Any ideas what to try next?
__________________

rwc is offline   Reply With Quote
Old 06-11-2022, 12:08 PM   #2
Admiral
 
mmwjr's Avatar
 
Join Date: Feb 2012
Location: Essex, Maryland
Posts: 10,606
Default

Measure to see if you have 12V at the breaker. No voltage check the fuse at the starter. Voltage check for 12V on the B terminal of the ignition switch.
__________________

__________________
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2

Mike
mmwjr is offline   Reply With Quote
Old 06-11-2022, 01:45 PM   #3
rwc
Lt. Commander
 
Join Date: Sep 2017
Location: Vancouver, Canada
Posts: 102
Default

Thank you!

Sorry for the dumb questions, but does the key need to be turned when checking the voltage at those points? Is the fuse at the starter the one between the positive battery cable and alt cable?

Would a bad starter cause this? I had a flood during a storm in September and the starter was immersed in seawater. It worked fine afterwards, so I thought I’d got away with it, but I read your comment in another post that an immersed starter never lies (which I presume means it doesn’t survive).
rwc is offline   Reply With Quote
Old 06-11-2022, 04:16 PM   #4
Admiral
 
mmwjr's Avatar
 
Join Date: Feb 2012
Location: Essex, Maryland
Posts: 10,606
Default

The key doesn’t need to be on but the battery switch does. There is a 90 amp fuse on the starters solenoid that supplies power to the breaker. Very seldom will a submersed starter not fail in the near future.
__________________
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2

Mike
mmwjr is offline   Reply With Quote
Old 06-11-2022, 06:21 PM   #5
rwc
Lt. Commander
 
Join Date: Sep 2017
Location: Vancouver, Canada
Posts: 102
Default

I get battery voltage on the larger lead to the 50A breaker and 10.4V on the other side. That doesn’t seem right. Bad breaker?

I’m assuming I should replace the breaker, replace the starter, and learn to moor better in storms?
rwc is offline   Reply With Quote
Old 06-11-2022, 06:31 PM   #6
rwc
Lt. Commander
 
Join Date: Sep 2017
Location: Vancouver, Canada
Posts: 102
Default

9.7V at ignition.

I can’t find anything I can reach on the starter that isn’t battery voltage or no reading, but it’s very difficult to see / reach with the battery in place, so might be missing the right spot.
rwc is offline   Reply With Quote
Old 06-11-2022, 06:53 PM   #7
Admiral
 
mmwjr's Avatar
 
Join Date: Feb 2012
Location: Essex, Maryland
Posts: 10,606
Default

Quote:
Originally Posted by rwc View Post
I get battery voltage on the larger lead to the 50A breaker and 10.4V on the other side. That doesn’t seem right. Bad breaker?

I’m assuming I should replace the breaker, replace the starter, and learn to moor better in storms?
Remove the wire from the 10.4V side to see if the voltage goes up, if not replace the breaker.
__________________
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2

Mike
mmwjr is offline   Reply With Quote
Old 06-11-2022, 06:54 PM   #8
Admiral
 
mmwjr's Avatar
 
Join Date: Feb 2012
Location: Essex, Maryland
Posts: 10,606
Default

Quote:
Originally Posted by rwc View Post
9.7V at ignition.

I can’t find anything I can reach on the starter that isn’t battery voltage or no reading, but it’s very difficult to see / reach with the battery in place, so might be missing the right spot.
9.7V on the coil is good as the wire is resistance and the voltage is prober. This also tells you the fuse on the starter is good.
__________________
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2

Mike
mmwjr is offline   Reply With Quote
Old 06-11-2022, 07:08 PM   #9
rwc
Lt. Commander
 
Join Date: Sep 2017
Location: Vancouver, Canada
Posts: 102
Default

Quote:
Originally Posted by mmwjr View Post
Remove the wire from the 10.4V side to see if the voltage goes up, if not replace the breaker.
Voltage went up to 12V with the smaller cable disconnected, so not the breaker then?
rwc is offline   Reply With Quote
Old 06-11-2022, 08:06 PM   #10
Admiral
 
mmwjr's Avatar
 
Join Date: Feb 2012
Location: Essex, Maryland
Posts: 10,606
Default

Quote:
Originally Posted by rwc View Post
Voltage went up to 12V with the smaller cable disconnected, so not the breaker then?
This is one of those that can go either way after thinking about it. If the breaker is resistive no load, wire removed can yield good voltage but add load and you get a voltage drop. Guess I would replace it.
__________________
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2

Mike
mmwjr is offline   Reply With Quote
Old 06-11-2022, 09:16 PM   #11
rwc
Lt. Commander
 
Join Date: Sep 2017
Location: Vancouver, Canada
Posts: 102
Default

Quote:
Originally Posted by mmwjr View Post
This is one of those that can go either way after thinking about it. If the breaker is resistive no load, wire removed can yield good voltage but add load and you get a voltage drop. Guess I would replace it.
I’ve got a spare starter, so I’ll start with that and see what happens. I think the breaker should be easy to get if the problem persists.

Mike, thanks so much (once again) for your help! Without it, I probably would not ever have a functioning boat.
rwc is offline   Reply With Quote
Old 06-27-2022, 03:17 PM   #12
rwc
Lt. Commander
 
Join Date: Sep 2017
Location: Vancouver, Canada
Posts: 102
Default

Just to close this one out, I had very corroded battery cable connections and the breaker would pop shortly after start up. After three or four times trying to track down the connection issue, I realized I’d missed a connection (the worst one). Cleaned them all up, but now no start at all.

Changed the starter to a spare, no effect. Changed the breaker as per mmwjr advice, and the engine fired right up. So guessing I must have cooked the breaker by overloading it too many times.
__________________

rwc is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Powered by vBadvanced CMPS v3.2.3

All times are GMT. The time now is 03:33 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.