Repairing low gas indicator light... expert needed !


Information and questions on GL1200 Goldwings (1984-1987)
  • Sponsored Links
User avatar
SilverDave
Posts: 366
Joined: Sun Aug 09, 2009 9:39 am
Location: Langley, BC
Motorcycle: 1985 GL1200 GoldWing Aspy

Repairing low gas indicator light... expert needed !

Postby SilverDave » Fri Mar 27, 2015 6:19 pm



The red low gas level light on my 1200 comes on at startup check..... but not at "almost Empty " so bulb is good.
As I understand it , this light is controlled by a wet-dry two resistance thermistor.... a NTC type.

Something like this :

http://www.newark.com/amphenol-advanced ... 582-97-T10

They cost more to ship that to buy ( about $2).

I want to chat with someone who has actually done this fiddly repair .... and what I'd like to know , if I decide to do this is any snags I might run into ........Is the soldering difficult ? How does one open the little can ? Is there any orientation needed ? Will this modern NTC from Newark actually fit in the little can? Any re-seal gaskets needed ?


Its not in either one of my GL1200 manuals .... they recommend replacing the entire unit ( !! )

I am assuming the little hanging down can in this pic is the thermistor unit as the other part looks like the float for the gas gauge.

http://i.ebayimg.com/00/s/MTIwMFgxNjAw/ ... l/$_35.JPG

Thanks for any help .

SilverDave



User avatar
HALBUDD
Posts: 844
Joined: Sat Aug 14, 2010 9:14 pm
Location: New Albany In
Motorcycle: 1984 gl1200a&1985GL1200A & 1996 gl 1500 aspy. us army 74-77

Re: Repairing low gas indicator light... expert needed !

Postby HALBUDD » Sat Mar 28, 2015 7:18 pm

I think there was a post on how to fix this a while back. I think if you try and do a search on this site it may come up. I remember WingAdmi had written some thing up on this .Good luck----------------------Hal
A woman that can use tools is worth her weight in gold !!

User avatar
WingAdmin
Site Admin
Posts: 17045
Joined: Fri Oct 03, 2008 4:16 pm
Location: Strongsville, OH
Motorcycle: 2000 GL1500 SE
1982 GL1100A Aspencade (sold)
1989 PC800 (wife's!)
1998 XV250 Virago (sold)
2007 Aspen Sentry Trailer

Re: Repairing low gas indicator light... expert needed !

Postby WingAdmin » Mon Mar 30, 2015 9:56 am

If it's the same as the GL1500 (and I suspect it is), it's a simple thermistor. When it's immersed in fuel, the fuel itself conducts heat away from it and keeps it relatively cool. When the fuel level drops below the thermistor, it warms up because the fuel is no longer conducting heat away from it, and its resistance changes. The dashboard detects the change in resistance and shows the low fuel light as a result.

It's not a very reliable system. That said, it can be replaced with a thermistor component that shouldn't cost you more than a couple dollars or so - if you know the correct resistance and whether it is a NTC or PTC. I'm 99.9% sure they are a NTC, in that its resistance drops when temperature rises, instead of the other way around.

That said, virgilmobile and I replaced these rather unreliable thermistors in our GL1500's with a float sensor and a flasher circuit that works extremely well. When my low fuel light starts to flash (and when it does, it's very attention-getting) I know I have exactly one gallon of fuel left (I calibrated it this way). You can read about it here:

viewtopic.php?f=14&t=11167

User avatar
SilverDave
Posts: 366
Joined: Sun Aug 09, 2009 9:39 am
Location: Langley, BC
Motorcycle: 1985 GL1200 GoldWing Aspy

Re: Repairing low gas indicator light... expert needed !

Postby SilverDave » Mon Mar 30, 2015 11:17 am

Yes , those thermistors are only about $1.10.... plus $20 shipping ....( agh !! ..).. I am looking into Ebay ones with the same hot-cold resistance .

Are they un-reliable because they fail from years of living in gas ?
or is the solder job the likely culprit ?
Or the possibly faulty ground of the can ?

I do like the float method that you and Virginmobile designed... but I'd like to try the simpler fix first....

SilverDave

User avatar
virgilmobile
Posts: 7644
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: Repairing low gas indicator light... expert needed !

Postby virgilmobile » Mon Mar 30, 2015 11:32 am

The component fails from age.It can be replaced but remember,It must be put back into the little canister.It is a "steady pond" design.If the thermistor is left hanging,sloshing gas will false trigger it.
This design will also not work well if you have replaced your low fuel lamp with a LED.

User avatar
WingAdmin
Site Admin
Posts: 17045
Joined: Fri Oct 03, 2008 4:16 pm
Location: Strongsville, OH
Motorcycle: 2000 GL1500 SE
1982 GL1100A Aspencade (sold)
1989 PC800 (wife's!)
1998 XV250 Virago (sold)
2007 Aspen Sentry Trailer

Re: Repairing low gas indicator light... expert needed !

Postby WingAdmin » Mon Mar 30, 2015 3:24 pm

SilverDave wrote:Yes , those thermistors are only about $1.10.... plus $20 shipping ....( agh !! ..).. I am looking into Ebay ones with the same hot-cold resistance .

Are they un-reliable because they fail from years of living in gas ?
or is the solder job the likely culprit ?
Or the possibly faulty ground of the can ?

I do like the float method that you and Virginmobile designed... but I'd like to try the simpler fix first....

SilverDave


I suspect it's simply years of gas immersion and heat, combined with years of power going through them. They just stop conducting. The one on my GL1500 looked perfectly intact, and when I disassembled it, all the solder joints were fine, so it was the component itself that failed.




Return to “GL1200 Information & Questions”




Who is online

Users browsing this forum: julimike54 and 2 guests