86 GT 150 melt down

[Jeremy420]

86 Johnson GT 150 VRO electrical system caught fire..

Had the boat out, did a little skiing it was running fine, finished skiing floated for a bit and then it wouldn't start -the battery was dead (there is no radio on the boat) Got it back to the docks.. later put a new battery in it and started it up - it ran fine. Turned it off and a few hours later the top of the motor cover had a hole melted through it!!! terrible electrical smell..

It looks like the regulator/rectifier is what started the small fire/ melt down. Now the motor cover is ruined and the wires around the top are fried.. it looks like the coils and spark plug wires are fine,the main harness is probably melted a little.

The whole motor its self doesn't look like it got too hot.. just the top is a little smoked colored... Do you think there is total damage to the electrical system? What about the motor?(I think its fine)

Any idea why this happened? I did notice a little electrical smell when it wouldn't start but didn't think enough about it I guess cause it was just barely noticeable.

I wonder if it would have lit up if I had been driving it at full throttle??

Any Ideas about where to find a new "cowling" or motor cover?

Thanks

 

[emdsapmgr]

Re: 86 GT 150 melt down

While unusual, this is not an isolated problem. When the hi-amp systems melt down they go all the way. You will probably need the regulator, stator, perhaps even a timer base and a harness. Also, check the flywheel to see if the magnets have been damaged or misaligned due to the heat. Most parts are available from your Bombardier dealer, except the cowl which is NLA. You can find these parts often on Ebay. Generally when this happens the customer contacts his insurance company and this is covered under the boat policy. If this will be insurance, replace everything so you don't have a failure later. Likely no damage to the block, other than discoloration.

 

[Dhadley]

Re: 86 GT 150 melt down

Actually it's pretty common with the 35 amp reg/rec. The tach probably quit working sometime prior to the fire. What happens is that salt, corrosion, sand etc builds up in the passages of the cooling system. At some point the passages over to the middle of the water chamber get plugged. Eventually the block traps air and doesnt fill completely to the top. The 35 amp reg / rec has cooling fins on the bottom that need to be in water. They won't disapate enough heat in air or steam. Some blocks just seem to naturally trap air at the top even with claen passages.

Eventually the reg / rec becomes hot enough that it shorts out inside. When it shorts out, it's very likely the wires will catch on fire. Next the fibergalss hood ends up with an extra vent hole.

On any motor I have that has a 35 amp system we vent the top of the cooling system to allow any air pocket to escape. That has always seemed to eliminate the problem.

 

[andy6374]

Re: 86 GT 150 melt down

Just following this thread.

Dhadely-
How do you vent? Just drill a hole?

 

[Jeremy420]

Re: 86 GT 150 melt down

Wow this forum is really active.. awesome!!!

Thanks for the tips so far guys!

Yes Dhadley, I noticed that the tach wasn't working right.. didn't know it was that critical.... or that it was a sign of things to come...

The tach must run off that electrical impulse from the Reg/rect, I'll look into how that works..

Thanks guys..

It sucks when your boat burns!!!

 

[Lodgepole]

Re: 86 GT 150 melt down

You might try Tim's Outboard Repair, Hackensack MN 218 682 2331
He has a salvage yard and I got a really nice hood and several other parts for a 78 Rude. Reasonable!

 

[Jeremy420]

Re: 86 GT 150 melt down

OK finally got this apart after a few attempts pulling the flywheel it finally popped free. The stator is a little melted and some plastic melted out of the little transformer(?) boxs so I think its probably bad too...

The timer base looks fine no signs of heat damage there but I have not removed it fully, should I remove it to check under it or anything?

All but 2 of the magnets in the flywheel have come loose, adhesive failure other than that they look fine. So what can be done with the flywheel? Can the magnet insert be changed? Looks like it would take a quite a process to do that..

I am going to attempt to repair the engine cowling myself with fiberglass, and paint it. The damage isn't too bad and the glassing fibers are still there.. never done it before but it can't be any worse than it is now...

 

[mikesea]

Re: 86 GT 150 melt down

you can epoxy the magnets back,just take a one edged razor blade to scrape off the old stuff that will come off,you can use 3/8 bolts to use as spacers,between magnets,Ive used JB weld

 

[emdsapmgr]

Re: 86 GT 150 melt down

If you are going to do an insurance claim, replace it all with new. If not, reglue the magnets. You won't know if the timer works till you get it all back together and check it's output. I'd check the light grease under it to make sure it still moves freely. How is the wiring harness?

 

[Jeremy420]

Re: 86 GT 150 melt down

I forgot to mention.. no insurance claim will be made. Thanks for the good news about the magnets! Ordering a new stator because I'm not sure about mine, but it may be ok it doesn't look too bad. Just a little blackend... slight wire melt but doesn't look like the wire is ruined..hmm.. As for the entire main harness; just the electrical tape wraped around it melted a little the wires are fine. The tilt still works..

Emd.. The wiring on the timer is fine, the fire was isolated enough that it only came right off the top of the Reg/rect. Not sure what you mean by light grease under it, sounds like I should pull it off and see if it spins freely.. I will probably use epoxy on the magnets, unless there is a better suggestion..

 

[jammer]

Re: 86 GT 150 melt down

No epoxy is good for reinstalling the magnets. Just of course clean it off good..use acetone..something like that. By the way when I had it done...the flywheel would have cost me about 800 bucks. You'll save a tone with redoing it yourself.

 

[Jeremy420]

Re: 86 johnson GT 150 melt down

Re: 86 johnson GT 150 melt down

I shattered one of the magnets cleaning it so I have a replacement. But then I chipped another one, cracked a little corner off while I was cleaning it.. Its a small chip about the size of the beveled corner that is already on them.. I would say its less than 5% of the magnet chipped off. should I get a new magnet for this one or do you think I can get by with it? This is the 35 amp system so I am wondering if its going to create a weaker spark on one cylinder? Its not much that is chipped off but I'm looking for advice.

 

[karlow1]

Re: 86 GT 150 melt down

I would try and find another flywheel. When you cook a magnet, it may lose it's magnetism. The other problem is it is likely to be out of balance after you repair it.
Good luck

 

[Dhadley]

Re: 86 GT 150 melt down

Replacing the magnets is OK, no problem. The trick is to clean the surface. We glass bead it but sanding lightly will work too. The epoxy glue that comes with the magnet works fine. We use a 2 part "A & B" type epoxy. Don't worry about the balance, it won't be any more aout of balance than it was from the factory. At rpms where it really matters we don't use that flywheel anyway.

The chipped one should be fine. However, if you are questioning it in your own mind, replace it. Not that big of a deal. No one single magnet makes juice for a single cylinder. The 35 amp designation refers to the charging system not the ignition system.