This was not my intention. I went to much detail, and the initial post was for "how to with what you have". 
Gauge testing-thought I would share
Le Mans Master
Joined: Aug 2006
Posts: 7,425
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Greatful.
Thank DWncchs for posting some solutions to problems that I may encounter some day. Happy belated Thanksgiving to you and yours.
Thanks to Willcox Inc. for your input. As a sponsor you go above and beyond the rest and thank you for that extra effort!
It's because of you and et al that realy makes this one of the best forums.
PG.
Thanks to Willcox Inc. for your input. As a sponsor you go above and beyond the rest and thank you for that extra effort!
It's because of you and et al that realy makes this one of the best forums.
PG.
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Roger,
I have something for you, but I can't find your email address. Email me at Willcoxcustomerservice@willcoxcorvette.c om You'll love it too!
Ernie
I have something for you, but I can't find your email address. Email me at Willcoxcustomerservice@willcoxcorvette.c om You'll love it too!
Ernie
Racer
Joined: May 2005
Posts: 417
Likes: 0
From: Red Deer Alberta
At least I wil never know how much $$ I waisted, or if I waisted any $$
because I just sent them in to be refurbished without testing.
I had no idea how at the time.
This is excellent step by step info
Thank you
JR
because I just sent them in to be refurbished without testing.
I had no idea how at the time.
This is excellent step by step info
Thank you
JR
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
Just a quick comment on the pots mentioned by Willcox. The pots used for guitars are 500,000 ohms range, not 500, and they are audio taper, which means the resistance doesn't change linearly as the pot is turned. Co-incidentally, there are linear taper pots available from electronics suppliers that would probably work better for guage testing. The audio taper is probably the cause of the touchiness at the far low end of the resistance scale. There are a number of very small pots designed to be mounted on PC boards that have a narrower range of resistance and take multiple turns of the screw to adjust, so one of these might work better for testing guages. Radio Shack probably carries these.
Rick B.
Rick B.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Rick,
I’ve never worked on a guitar
so I’m not real familiar with what they use. I assumed they were the same. (assumed wrong).
What I use in the test machine in our shop is a series of four 100 ohm linear taper pots combined with two that are 150 ohm. I think I pasted the link above but here is a cheap supplier for them.
http://www.allelectronics.com/make-a...TAPER/-/1.html
Willcox
I’ve never worked on a guitar
so I’m not real familiar with what they use. I assumed they were the same. (assumed wrong).What I use in the test machine in our shop is a series of four 100 ohm linear taper pots combined with two that are 150 ohm. I think I pasted the link above but here is a cheap supplier for them.
http://www.allelectronics.com/make-a...TAPER/-/1.html
Willcox
Last edited by Willcox Corvette; May 20, 2009 at 07:30 PM.
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Brett Foote
Team Owner
Joined: Sep 2006
Posts: 31,235
Likes: 4,326
From: Westminster Maryland
Hi Willcox,
I just looked at your fuel sender diagram again... I believe that by 71 (maybe 68) there's just 1 wire running to the sender and then the ground connection.
Getting the parts from the electronics store to make the potentiometer is cheap and easy like you said and is quite useful.
This still such a useful thread; gauges can be SUCH a puzzle!!!!
Regards,
Alan
PS: In the new DRIVELINE, Al K. notes that he can make door panels with the original fiberboard backing for $300 extra. I'm wacko enough to want one.
I just looked at your fuel sender diagram again... I believe that by 71 (maybe 68) there's just 1 wire running to the sender and then the ground connection.
Getting the parts from the electronics store to make the potentiometer is cheap and easy like you said and is quite useful.
This still such a useful thread; gauges can be SUCH a puzzle!!!!
Regards,
Alan
PS: In the new DRIVELINE, Al K. notes that he can make door panels with the original fiberboard backing for $300 extra. I'm wacko enough to want one.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Alan,
Yep! You are correct! I have a new schematic just for the 68-77 cars. I'm about to put up some new pages on all the gauges and senders. This way it should end most of the questions and/or make it easy for people to know what is required to make the gauges work.
Below is one on the oil temp gauge if it helps this person above.
2box,
Have you tested the wires on the connector for power, ground and ohms input?
Yep! You are correct! I have a new schematic just for the 68-77 cars. I'm about to put up some new pages on all the gauges and senders. This way it should end most of the questions and/or make it easy for people to know what is required to make the gauges work.
Below is one on the oil temp gauge if it helps this person above.
2box,
Have you tested the wires on the connector for power, ground and ohms input?
Last edited by Willcox Corvette; May 21, 2009 at 03:10 PM.
Safety Car
Joined: May 2008
Posts: 3,751
Likes: 720
From: Lafayette Louisiana
Another piece of info
I printed out the original post of this info as this is quite useful when trying to figure out my gauges on the 76.
I think DW's post (maybe, I am not sure where I read this now) said if the resistor is bad across the back of the oil gauge, for example, then the gauge would go about a 1/3 of the way up and stay there. This resistor across the back of the oil gauge is not part of the gauge body, but is a strip of maybe paper with nichrome (?)wire wrapped around it to get the proper resistance.
I found out recently that my paper resistor was bad and so that was the problem with my oil gauge. The oil gauge itself was fine. There is another paper resistor similar to this on the fuel gauge I think.
Hope this is helpful.
I think DW's post (maybe, I am not sure where I read this now) said if the resistor is bad across the back of the oil gauge, for example, then the gauge would go about a 1/3 of the way up and stay there. This resistor across the back of the oil gauge is not part of the gauge body, but is a strip of maybe paper with nichrome (?)wire wrapped around it to get the proper resistance.
I found out recently that my paper resistor was bad and so that was the problem with my oil gauge. The oil gauge itself was fine. There is another paper resistor similar to this on the fuel gauge I think.
Hope this is helpful.
Last edited by 20mercury; Mar 2, 2011 at 11:56 PM.
