68 327 running cold
Thread Starter
Instructor
Joined: May 2011
Posts: 169
Likes: 2
From: petaluma california
now to figure out if i need new heat riser or spacer,,,spring and summer will be here soon enough...hopefully there isnt any internal damage to the numbers matching L79,,,thx
Le Mans Master
Joined: Jan 2001
Posts: 6,743
Likes: 1,385
I recommend the Willcox temp gauge adjustable resistor contraption. I lived with my low-reading gauge for years (decades?) and it was so easy to fix. Take a look.
https://www.corvetteforum.com/forums...-question.html
https://www.corvetteforum.com/forums...-question.html
Jebby thankyou for you help, i pickup up the infared at harbor freight and warmed the car up,,,got a reading as high as 192 at the therm housing so 7T1 you were right the guage in the car is incorrect... running a new 195 degree thermostat.
now to figure out if i need new heat riser or spacer,,,spring and summer will be here soon enough...hopefully there isnt any internal damage to the numbers matching L79,,,thx
now to figure out if i need new heat riser or spacer,,,spring and summer will be here soon enough...hopefully there isnt any internal damage to the numbers matching L79,,,thx
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Jebby thankyou for you help, i pickup up the infared at harbor freight and warmed the car up,,,got a reading as high as 192 at the therm housing so 7T1 you were right the guage in the car is incorrect... running a new 195 degree thermostat.
now to figure out if i need new heat riser or spacer,,,spring and summer will be here soon enough...hopefully there isnt any internal damage to the numbers matching L79,,,thx
now to figure out if i need new heat riser or spacer,,,spring and summer will be here soon enough...hopefully there isnt any internal damage to the numbers matching L79,,,thx
Jebby
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
When engine is cold, just reach down with your hand and see if you can freely move the counter-weight on the heat riser valve (at outlet of exhaust manifold). If that moves freely, you don't have a frozen heat riser valve. Now, to be certain that it won't freeze up, you can either wire it in the OPEN position or take the riser valve of and cut the valve plate off its shaft.
If you do a lot of cold weather driving in your C3 (
???), you may want to leave the heat riser valve in place. Just check it regularly and put some hi-temp grease on the shaft ends occasionally.
If you do a lot of cold weather driving in your C3 (
???), you may want to leave the heat riser valve in place. Just check it regularly and put some hi-temp grease on the shaft ends occasionally.
Racer
Joined: Nov 2010
Posts: 310
Likes: 25
From: Brisbane Australia
Just a note that most repro temp senders listed for a 68 are rubbish and the gauge will read low. The one I got from Lectric was close but still hardly ever read over 140 degrees. Ended up getting one of the variable resistors a few vendors sell and tuning the gauge to the sender, confirming the temp readings with an IR gun.
