Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

[teritch]

I had the alternator changed and when I rev above 3K rpm it blows the 50 amp fuse, still runs great but when the fuse trips it pegs the voltage guage. All of my insturments are normal except for the pegged voltage meter until I killl the motor and when I try to start it again everything on the insturment panel is dead until I reset the fuse. I My fuel guage is also out, could this be related?
Before I changed the alternator when this fuse tripped it would run rough.

 

[bnicov]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

Was the alternator rebuilt or replaced?? If replaced, was it the correct alternator?? Make sure you have the right one.

 

[Don S]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

That fuse should never trip, unless you have a direct short. Since it was tripping before the alternator was replaced, you really need to find the short.

 

[Don S]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

Found it

Have a look at this service bulletin. You probably don't have a short, just a wiring problem that needs fixed. Of course you may have alternator problems again. They don't like running with no place for the voltage to go.


View attachment 37-2-3_A.pdf

 

[teritch]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

Was the alternator rebuilt or replaced?? If replaced, was it the correct alternator?? Make sure you have the right one.

I took the part number from the old one and researched it before I bought one. I gave the mechanic a wiring diagram that I pulled from the net specific to the motor/drive. After posting that yesterday I puled it and checked his wiring and it was not wired per the diagram. I corrected it and still have the same problem.
I have had this boat for years and and remember what it did when this fuse blew in the past, this was not a problem before the alternator change but there have been a lot of different hands under the hood so anything is possible.

If I had a short I thought that it wouild blow the fuse at start up, not after reaching a certain rpm?

There are two of the 50 amp resettable fuse links daisy chained together, this is the second one in the loop, if I switch places with them and the same one still blows would it prove the fuse to be the problem? They are about $100 so I don't want to just run buy one.

Thanks for the help!

 

[Don S]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

You was probably typing when I was posting, did you see the service bulletin I posted above?

 

[teritch]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

Thanks Don, this looks like what I need!! I will try it and let you know!

 

[teritch]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

Hey Don!! That worked, it passed the grage check and I will test it in the water this afternoon. I can't thank you enough for takin the time to share your knowledge and abilities with me!

Should I see a short from the sending unit in the tank, or how would you look for a problem with the fuel guage??

 

[Don S]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

You was lucky. After my original post, I remembered something about the wiring on the early OMC/Volvo joint venture engines just couldn't remember what. Looked in the manuals and the wiring diagrams are just junk for those years, then just started looking through service bulletins until I found it.

For your fuel gauge, do a search over in the electrical forum, that has been posted and answered hundreds of times.

 

[teritch]

Re: Alternator problems? 1996 4.3 Volvo Penta Engine ID#4110124372

That was definitely a design flaw. Input from the alternator should not have been on that side of the fuse in the first place! Oh, and I was very lucky. Lucky to have you in my corner on this one!!! To you this may not be a big deal but this meant the world to me and I was praying that I found someone like you to help!

Much Respect and Many Thanks, Terry

P.S. I had the most romantic moonlight cruise last night! Early spring evening and we just beat the storm back to the dock!
I have had this boat since 99 it's taught my three sons and all of their friends to wakeboard. I have to sell it now and will replace it in a few years when the grand kids get old enough to play in the water with me. The Volvo Penta has been strong and dependable for years. That's the way I want to go, any suggestions??