So 3rd alternator belt down and almost a summer wasted.........

[CUE99T]

So wondering if the alternator is sticking on our GT-40 engine........

We've done 3 belts this season and getting right fed up with it now as we love the boat other than this.

[CUE99T]

So was a touch tired when posting the previous comment......

What I mean to say was what's causing this do you reckon?

Nautique dealer says its not rusty, as he's cleaned it all up, it's not misaligned or over tightened.....so what could it be?? Sticking alternator? They have been great and even gave us a belt for free but that's us 3 down this season, all melted right off!! Or the fact we have an iPod into our stereo now and could it be trying to do excessive things with the stereo? Could it be as simply as that?

Justo fitted new perfect pass so bursting to get more sets done with this good weather but its tormenting me, I mean do we just have to bite the bullet and get a new alternator??? The current one seems to spin freely and is rust free so hating the thought of shelling out for a new one and it does the same!!!

Any thoughts appreciated chaps!!

Paul

[AirTool]

can you post a pic of the "smoked" belt?

[Mikeski]

If it were me it would get a new alternator. I have seen the bearings in car alternators go bad where they seem to spin freely then randomly lock up. At least with the GT 40 you know it is only the alternator since it has a dedicated belt.

[AirTool]

If it were me it would get a new alternator. I have seen the bearings in car alternators go bad where they seem to spin freely then randomly lock up. At least with the GT 40 you know it is only the alternator since it has a dedicated belt.

I agree....the only other thought I had was the voltage regulator was switching it to full amps and loading up the belt. I've seen that before but what happens then is the battery boils over LOL.

One time, the VR in the Firebird I had in high school stuck such that amps was proportional to engine speed. When I revved the engine, I could see it on the amp meter I had installed aftermarket. It followed the engine all the way up to 60 amps. I could also hear it in the radio and see it in the lights.

I'm pretty sure his bearing has enough drag to ruin the belt at high engine speed. If its alignment, it would probably be coming off...not smoking.

Edit: if you order a new alternator...save the old one and change out the bearings.

[surroundsound64]

Ditto. Sounds like an alternator replacement will save you from smashing your head in.

[CUE99T]

Cheers chaps. That's what I'm suggesting but my co-owner has a view that if its running freely then it must be alignment or something, but to the mechanic who out belt 2 on, it looked in alignment. Its getting checked again tomorrow and my view is a new unit just gets the issue out the way, as its been gorgeous this week and no boat has severely hacked me off!!

[charlesml3]

Well, I'd like to suggest another test but it's going to cost you another belt. As soon as the belt breaks, open the cover and see how hot the alternator is. Yes, it's going to be pretty warm since it's inside the engine compartment but it shouldn't be so hot you can't keep your hand on it.

If it's really hot then it's not breaking the belt, it's melting it. If so, you need to start isolating the problem. First thing I'd do would be to replace the battery. If the battery isn't taking a charge like it should the alternator will work way too hard trying to keep it charged.

If that isn't it, then it's probably the voltage regulator inside the alternator. If it's bad it'll overcharge like crazy and you should see this on the ammeter gauge on your dash. If this is the case, you want to fix the problem really soon because it'll ruin the battery and you'll be replacing both.

-Charles

[CUE99T]

Cheers for the comments.

There is 2 brand new batteries so its not batteries.

It appears to melt the belt when the boat goes under load, I.e. powering up the rev range when actually in the water, but revving at the dock side didn't seem to cause the fault. It seemed to be a clean break for 98% of the belt but the top 2% of the belt seemed to cheer off at 6inches away from that but it was a clean break at both bits. Probably heated up and just snapped.

That any better a clue?

We've sent the Alt away for repair as its 300 pounds for a new one.

On the up side, our new PP split screen is very nice!!! Lol

[CUE99T]

So brand new alternator on this afternoon, ran for about a minute and it was roasting hot within a couple of minutes!! Seems a battery has now gone a bit bad which is mad as it was 2 new batteries but I have others so can easily swap them out.

Dealer thinks its electrical fault somewhere. Could this be why our Perfect Pass module fried?

Any ideas chaps??
Paul

[bhectus]

How do you have your batteries wired together?

[charlesml3]

I think we're on the right path here. So we know the alternator is working WAY too hard and getting hot which is what's breaking your belt.

So let's start looking at that. Trace the heavy red wire from the alternator all the way to the battery. Make sure it isn't worn through somewhere. Same thing for the black ground wire coming off the negative terminal of the battery. It's probably attached to the block somewhere. Take that off, clean it thoroughly and reattach.

Swap those batteries out. Actually, go down to one battery until we find the problem. Get all of this done and run it again only on a single battery. Does the alternator get really hot again?

-Charles

[CUE99T]

Thanks Charles, its going in on Wed to Scotland Nautique to do what your suggesting.

Fingers crossed its back in a few days as the water has been awesome and I've been out on the school boat but not ours which is pretty depressing since its been toasting the last 3 weeks!!!

Will let you know the results later in week.

[charlesml3]

Please do! The mystery is killing me. There just HAS to be something that's causing a huge draw.

Thanks!

-Charles

[djw383]

Hello! I am having this same issue and the end of this story was not told. Does anyone know what corrected the issue with the meting belt?

Thank you!