temp gauge issue - CorvetteForum - Chevrolet Corvette Forum Discussion


C3 Tech/Performance
V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette

temp gauge issue

Reply
 
 
 
Thread Tools Search this Thread
Old 08-27-2017, 03:26 AM   #1
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default temp gauge issue

ive got a 69/350 and the temp gauge/wiring is all stock.

my issue is that it seems to be reading low. its been doing this for the last season or two now, and iive finally decided to get around to sorting it out.

ive followed willcox guide on testing, and everything has passed. ive put a new thermostat in, and a new temp sending unit.

under normal driving conditions, it reads on the high side of the 100 notch. when its "hot" itll reach the 1/4 mark, as soon as i start getting some air moving, the temp drops right back off. so it appears the gauges are working, but theres a calibration issue someplace?

i havnt worried about it too much, its just time to get it fixed. ever since i had my radiator cleaned, and put in all the new baffles for it, i knocked off an easy 30-40 degrees under full load.
another-user is offline   Reply With Quote
Old 08-27-2017, 01:10 PM   #2
carriljc
CF Senior Member
 
carriljc's Avatar
 
Member Since: Jan 2001
Posts: 1,598
Thanked 68 Times in 64 Posts
Default

go to the Willcox website and order the Temp Gauge adjustment contraption they sell. Worked great to tweak my temp gauge to read correctly. Easy too.

https://willcoxcorvette.com/corvette...resistor-68-76

my installation story:
https://www.corvetteforum.com/forums...-question.html


Quote:
Originally Posted by another-user View Post
ive got a 69/350 and the temp gauge/wiring is all stock.

my issue is that it seems to be reading low. its been doing this for the last season or two now, and iive finally decided to get around to sorting it out.

ive followed willcox guide on testing, and everything has passed. ive put a new thermostat in, and a new temp sending unit.

under normal driving conditions, it reads on the high side of the 100 notch. when its "hot" itll reach the 1/4 mark, as soon as i start getting some air moving, the temp drops right back off. so it appears the gauges are working, but theres a calibration issue someplace?

i havnt worried about it too much, its just time to get it fixed. ever since i had my radiator cleaned, and put in all the new baffles for it, i knocked off an easy 30-40 degrees under full load.

Last edited by carriljc; 08-27-2017 at 01:15 PM.
carriljc is online now   Reply With Quote
The Following User Says Thank You to carriljc For This Useful Post:
Willcox Corvette (08-27-2017)
Old 08-27-2017, 09:14 PM   #3
Willcox Corvette
Premium Supporting Vendor
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 60,438
Thanked 757 Times in 684 Posts
Default

Quote:
Originally Posted by another-user View Post
ive got a 69/350 and the temp gauge/wiring is all stock.

my issue is that it seems to be reading low. its been doing this for the last season or two now, and iive finally decided to get around to sorting it out.

ive followed willcox guide on testing, and everything has passed. ive put a new thermostat in, and a new temp sending unit.

under normal driving conditions, it reads on the high side of the 100 notch. when its "hot" itll reach the 1/4 mark, as soon as i start getting some air moving, the temp drops right back off. so it appears the gauges are working, but theres a calibration issue someplace?

i havnt worried about it too much, its just time to get it fixed. ever since i had my radiator cleaned, and put in all the new baffles for it, i knocked off an easy 30-40 degrees under full load.
At some point, someone has probably changed the sender. All aftermarket senders fail... (it's very rare to get one that reads correctly even in the so called "Exact" reproductions).

The adjustable resistor should cure your issues... this is exactly why we made them

Willcox
Willcox Corvette is offline   Reply With Quote
Old 08-27-2017, 10:43 PM   #4
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default

Quote:
Originally Posted by Willcox Corvette View Post
At some point, someone has probably changed the sender. All aftermarket senders fail... (it's very rare to get one that reads correctly even in the so called "Exact" reproductions).

The adjustable resistor should cure your issues... this is exactly why we made them

Willcox
looking at the video, im wondering if my resistor just went bad?

its an original one, and the temp gauge has worked fine for the previous 10 years ive had the car. but when i pulled the gauge cluster apart to clean and repaint, thats when i first started having an issue.
another-user is offline   Reply With Quote
Old 08-28-2017, 10:07 PM   #5
Willcox Corvette
Premium Supporting Vendor
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 60,438
Thanked 757 Times in 684 Posts
Default

Checking the old resistor is easy.. remove it from the gauge and test it for ohms from one side to the other.. While 90 is the given standard, it can deviate from around 85-92 ohms.

Willcox
Willcox Corvette is offline   Reply With Quote
Old 09-08-2017, 04:02 PM   #6
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default

so im not sure if the resistor is bad, or my el cheapo multimeter is bad. the resistor reads as low as 87.9, but the multimeter shows spikes all over up to 150ohms. kinda leaning towards a busted resistor?
another-user is offline   Reply With Quote
Old 09-08-2017, 06:51 PM   #7
Willcox Corvette
Premium Supporting Vendor
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 60,438
Thanked 757 Times in 684 Posts
Default

Quote:
Originally Posted by another-user View Post
so im not sure if the resistor is bad, or my el cheapo multimeter is bad. the resistor reads as low as 87.9, but the multimeter shows spikes all over up to 150ohms. kinda leaning towards a busted resistor?
I'd question the meter... the resistance should be aprox. 90 ohms with the resistor disconnected from the gauge.
Willcox Corvette is offline   Reply With Quote
Old 09-09-2017, 01:52 AM   #8
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default

Quote:
Originally Posted by Willcox Corvette View Post
I'd question the meter... the resistance should be aprox. 90 ohms with the resistor disconnected from the gauge.
i just cleaned both ends of the resistor and measured it on my desk (wood) its in the 88ohm range (saw as high as .9 and as low as .3)

so, assuming the resistor is good, what should i look for next?

i know my gauge is moving, but its barely coming above the big 100* mark under normal operation, and 3/4-ish way to the 180* when its hot.

as soon as they car starts moving when its hot, i can watch the needle drop back down to that 100* mark.

before i cleaned the radiator and put the baffles back in, i used to see it go to the right of 210* on occasion. and before i cleaned my gauge cluster, i saw it hover around 180* mark. its only been since i reassembled everything that the issue has cropped up.

Last edited by another-user; 09-09-2017 at 01:55 AM.
another-user is offline   Reply With Quote
Old 09-09-2017, 02:34 PM   #9
carriljc
CF Senior Member
 
carriljc's Avatar
 
Member Since: Jan 2001
Posts: 1,598
Thanked 68 Times in 64 Posts
Default

here, go do this testing. Should help you determine issue:
http://repairs.willcoxcorvette.com/1...erature-gauge/
carriljc is online now   Reply With Quote
Old 09-10-2017, 11:53 AM   #10
Willcox Corvette
Premium Supporting Vendor
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 60,438
Thanked 757 Times in 684 Posts
Default

Testing a 68-76 Temperature Gauge -or- What your non working gauge can tell you!
Willcox Corvette is offline   Reply With Quote
Old 09-10-2017, 12:16 PM   #11
'75
CF Senior Member
 
'75's Avatar
 
Member Since: Dec 2007
Location: McHenry Illinois
Posts: 5,379
Thanked 239 Times in 229 Posts
Default

Has the needle been off the gauge Maybe it just needs to be reset to a known point on the gauge with a certain resistance.
'75 is offline   Reply With Quote
Old 09-11-2017, 08:55 PM   #12
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default

i just put the resistor back in, and i had the opposite problem. it wouldnt stop climbing. after about 2 mins it was past 210*. and i know it wasnt that hot.

i just pulled the my entire cluster out this afternoon. ill look into it and get some pics up of what im looking at.
another-user is offline   Reply With Quote
Old 09-12-2017, 06:11 PM   #13
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default













i dont know if it means anything, but my seat belt warning light doesnt work anymore either. not sure what happened there.

Last edited by another-user; 09-12-2017 at 06:11 PM.
another-user is offline   Reply With Quote
Old 09-12-2017, 06:12 PM   #14
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default












i dont know if it means anything, but my seat belt warning light doesnt work anymore either. not sure what happened there.


found the issue with the no seat belt warning light. blown gauge cluster fuse. now riddle me this... why did my battery/gas/ temp gauge(kinda) work, when the gauge cluster fuse was blown?

not that any of this solves the tamp gauge reading incorrectly still.

Last edited by another-user; 09-12-2017 at 06:48 PM.
another-user is offline   Reply With Quote
Old 09-13-2017, 11:32 AM   #15
Willcox Corvette
Premium Supporting Vendor
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 60,438
Thanked 757 Times in 684 Posts
Default

What is all the silver foil stuff on the back of the housing? Is this possibly touching something?

If the gauge is working properly, you should be able to remove the ohms wire and it show as it does in the video. If you ground out the ohms wire it should do the same as the video posted above. If it works this way then your gauge is probably fine. If it doesn't then you have a gauge issue. Each of the test below should read exactly how it is pictured... any variance would mean you have a gauge issue. Lets say you ground out the ohms wire and the needle is at 4 o'clock... then there is an issue. Either the needle has moved or the gauge is toast.



Find a known source for your ohms input.. Or take a couple of flashers, take an ohms reading off of them in a series. Typically it's around 50 ohms so if you use two of these you'll be around 100 ohms input..

Put 12 volts on the gauge power terminal, ground on ground and put the flasher in line. With 100 ohms input the gauge should go to right around the first mark. (aprox).

Or (the smartest thing for testing gauges) you could just purchase an adjustable pot online... set the reading to 79 ohms... the gauge should read 210 degrees... This will tell you if the gauge is working properly and if it goes to some other reading then remove the needle, set the pot to 79 ohms and re-set the needle.




Or..........................

You could just send the gauge to me and I'll put it on the tester. If you wish to do this email me at [email protected]

Last edited by Willcox Corvette; 09-13-2017 at 11:32 AM.
Willcox Corvette is offline   Reply With Quote
Old 09-13-2017, 08:56 PM   #16
another-user
CF Senior Member
Thread Starter
 
another-user's Avatar
 
Member Since: Jun 2005
Posts: 3,760
Thanks: 0
Thanked 3 Times in 1 Post
Default

got it going. it was the aluminum tape i used when i upgraded to LED light strips in the housing (needed a good reflective backing to get some bright, readable gauges in the car finally). turned out one of the studs was touching the tape.

now, next question. do you carry the ammeter condensers that go on the back of the gauge cluster? i cant find them on the site. the wire fell out of mine when i was putting things back together today...
another-user is offline   Reply With Quote
Old 09-14-2017, 06:36 PM   #17
Willcox Corvette
Premium Supporting Vendor
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 60,438
Thanked 757 Times in 684 Posts
Default

Quote:
Originally Posted by another-user View Post
got it going. it was the aluminum tape i used when i upgraded to LED light strips in the housing (needed a good reflective backing to get some bright, readable gauges in the car finally). turned out one of the studs was touching the tape.

now, next question. do you carry the ammeter condensers that go on the back of the gauge cluster? i cant find them on the site. the wire fell out of mine when i was putting things back together today...


Just answered your email..
Willcox Corvette is offline   Reply With Quote
Old 09-15-2017, 09:01 AM   #18
carriljc
CF Senior Member
 
carriljc's Avatar
 
Member Since: Jan 2001
Posts: 1,598
Thanked 68 Times in 64 Posts
Default

I would get rid of that metallic tape. If you need better light reflection, then you can just paint (I used white paint for mine)..... all that metallic tape can only create future problems as it unpeels and whatnot.
As far as that condensor(capacitor) - I just purchased a standard ignition condensor(capacitor), and (for the condensor behind my tach) I soldered on the old connector so I could plug it right into the harness.



Quote:
Originally Posted by another-user View Post
got it going. it was the aluminum tape i used when i upgraded to LED light strips in the housing (needed a good reflective backing to get some bright, readable gauges in the car finally). turned out one of the studs was touching the tape.

now, next question. do you carry the ammeter condensers that go on the back of the gauge cluster? i cant find them on the site. the wire fell out of mine when i was putting things back together today...
carriljc is online now   Reply With Quote
Go Back   CorvetteForum - Chevrolet Corvette Forum Discussion >
Reload this Page
  • temp gauge issue
  •  
     
    Reply

    Related Topics
    Thread Thread Starter Forum Replies Last Post
    Help troubleshooting cooling issue Darinm C3 Tech/Performance 4 05-15-2017 11:44 AM
    1979 Temperature Gauge reading issues brand692 C3 Tech/Performance 6 04-17-2017 09:16 PM
    Printed circuit board Bill Jones C3 Tech/Performance 7 01-21-2017 06:28 PM
    Temp gauge issue vannmike C3 Tech/Performance 23 04-08-2016 10:59 PM
    Fuel, water temp and oil pressure gauges not working properly. Qkslvrc5z C5 Tech 7 01-10-2016 06:37 AM


    Thread Tools Search this Thread
    Search this Thread:

    Click for Advanced Search

    Posting Rules
    You may not post new threads
    You may not post replies
    You may not post attachments
    You may not edit your posts

    BB code is On
    Smilies are On
    [IMG] code is On
    HTML code is Off
    Trackbacks are Off
    Pingbacks are Off
    Refbacks are Off

    Forum Jump

    Sponsored Ads
    Vendor Directory

    All times are GMT -4. The time now is 11:42 AM.


    We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
     
    • Ask a Question
      Get answers from community experts
    Question Title:
    Description:
    Your question will be posted in: