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General Category => Yamaha FJ1100 / FJ1200 Running Problems => Topic started by: BristolFJ12Russ on April 20, 2019, 12:20:40 PM

Title: Smoking Alternator!
Post by: BristolFJ12Russ on April 20, 2019, 12:20:40 PM
Had a quick blast on a hot day - first noticed that the indicator was erratic then the engine cut out briefly.  Drove on 2 minutes and then saw plenty of white smoke coming out of the alternator.   When it was cool I saw it had blown one of the 30amp fuses.  I put a 15 amp in and turned on the ignition and it immediately popped.  I put a 30amp in and it ran and the alternator started to smoke again so have turned it off. 

Is this as simple as a new alternator or do i need to get the electrics checked over - i dont have a multimeter and even if i did i dont know how to use one... electric trickery is witchcraft.

any suggestions or solutions?  I wanted to go for a long ride tomorrow!
Title: Re: Smoking Alternator!
Post by: ZOA NOM on April 20, 2019, 02:12:03 PM
Sounds like you fried the alternator, but the short circuit could be external to it. Time to replace the alternator and trace the wiring to see if a chafed wire somewhere along its path is causing the short.
Title: Re: Smoking Alternator!
Post by: aviationfred on April 20, 2019, 02:19:09 PM
For starters, check the Red connector. That is the wires from the Alternator to the battery. It is a common occurance for the connector to get over heated and melt, allowing the pins to corrode and sometimes come into contact with each other. Other members have had the connector look fine, but when taken apart, they find charred and melted plastic.

Definitely find someone who is proficient with a Multimeter and check the wires. Much cheaper to find a chafed wire that is grounded to the frame than spend $300.00 on a new alternator, only to have the 30 amp fuse blow when you try starting the bike.

Even after checking the wiring and finding it all good or repairing the connector and/or the chafed wires. In my professional opinion, (I am an electrician by trade). I would replace the Alternator. In most cases, once you let the magic smoke out of electrical components, you can't put it back in.

Error on the side of caution, there have been a few FJ owners who have had their FJ's literally burn to the ground due to various issues.

Fred
Title: Re: Smoking Alternator!
Post by: Tuned forks on April 20, 2019, 06:02:25 PM
Quote from: aviationfred on April 20, 2019, 02:19:09 PM
In most cases, once you let the magic smoke out of electrical components, you can't put it back in.

  :biggrin:
I used to have an instructor that said something similar.  Once you let the factory smoke out, we can't put it back in.  Only the factory can do that.

Joe
Title: Re: Smoking Alternator!
Post by: ZOA NOM on April 20, 2019, 06:13:39 PM
Quote from: aviationfred on April 20, 2019, 02:19:09 PM

Error on the side of caution, there have been a few FJ owners who have had their FJ's literally burn to the ground due to various issues.

Fred

See my user pic...
Title: Re: Smoking Alternator!
Post by: Pat Conlon on April 20, 2019, 07:37:29 PM
Quote from: BristolFJ12Russ on April 20, 2019, 12:20:40 PM
..... I wanted to go for a long ride tomorrow!

^^^Not going to happen, at least with that bike.

You let the magic smoke escape from the alternator circuit.

Quote from: BristolFJ12Russ on April 20, 2019, 12:20:40 PM
i dont have a multimeter and even if i did i dont know how to use one... electric trickery is witchcraft.

Please seek and get professional help.  Any technical explanation I post will be futile.
Title: Re: Smoking Alternator!
Post by: aviationfred on April 21, 2019, 12:10:04 AM
My recommendation is to purchase this http://rpmracingca.com/proddetail.asp?prod=Alternator (http://rpmracingca.com/proddetail.asp?prod=Alternator)
and the XJR mounting bolts (FJ bolts are too short). The connector on the XJR alternator is different than the FJ connector.

I use Molex connectors as replacement for worn or damaged connectors on my FJ. https://www.bing.com/images/search?view=detailV2&id=D3BAF9887727C8F46AF1077F0D6F6103F6B37D76&thid=OIP.rsX0j_hwVlZcvbqfEe5YxwHaFj&mediaurl=http%3A%2F%2Fi.ebayimg.com%2Fimages%2Fi%2F252449344394-0-1%2Fs-l1000.jpg&exph=750&expw=1000&q=molex+connector&selectedindex=3&ajaxhist=0&vt=0 (https://www.bing.com/images/search?view=detailV2&id=D3BAF9887727C8F46AF1077F0D6F6103F6B37D76&thid=OIP.rsX0j_hwVlZcvbqfEe5YxwHaFj&mediaurl=http%3A%2F%2Fi.ebayimg.com%2Fimages%2Fi%2F252449344394-0-1%2Fs-l1000.jpg&exph=750&expw=1000&q=molex+connector&selectedindex=3&ajaxhist=0&vt=0)



Fred
Title: Re: Smoking Alternator!
Post by: BristolFJ12Russ on April 21, 2019, 11:05:01 AM
I did have visions of my bike going up in flames..   bought an XJR alternator for cheap on ebay off a low miles bike.. ill took a look and the black wire was melted inside the alternator - the rest of the wiring is fine so leaves me wondering why it let loose.

Ive lost my 12mm socket so i cant see what bolts i need - Fred do you know what size bolts i need to order?

cheers!

Title: Re: Smoking Alternator!
Post by: aviationfred on April 21, 2019, 03:16:23 PM
Quote from: BristolFJ12Russ on April 21, 2019, 11:05:01 AM
Fred do you know what size bolts i need to order?

cheers!


Order 3 of the part listed at #19 on the parts list.

https://www.motorcyclespareparts.eu/en/yamaha-parts/2010-xjr1300-motorcycles/generator (https://www.motorcyclespareparts.eu/en/yamaha-parts/2010-xjr1300-motorcycles/generator)


Fred
Title: Re: Smoking Alternator! (Fixed)
Post by: BristolFJ12Russ on May 17, 2019, 04:31:14 PM
so i bought some titanium bolts because i like shiny things, cleaned up the alternator and fitted it (tight fit!).  The plugs are different so i have a temporary connector but it all works and definately like the look of it.

First pic is the the roasted regulator... the rest of the unit looks good.  If anyone wants it give me a shout and you can have it for postage
Title: Re: Smoking Alternator!
Post by: BristolFJ12Russ on May 17, 2019, 04:36:26 PM
and 70 miles later.. ready for a night of Bivvy!