1967 GMC C1500 Mechanical Water Temp Gauge

JSBURTON69

MEMBER
1967 GMC C1500

Engine Cooling problem
1967 GMC C1500 V8 Two Wheel Drive Automatic? Miles

will a mechanical water temperature gauge go bad after the copper tubing has been in contact with the header. Temp gauge goes from 190 to 230+ during thermostate cycle, I've also replaced the thermostate thinking it was sticking, then noticed temperature copper lead was touching the header.

3 Replies

DR LOOT

MECHANIC
2,311 POSTS

Only if the copper line has been damaged, because it was touching the exhaust manifold that would explain why the temperature went up to 230 °

Was this

answer

helpful?

Yes

No

Sunday, December 13th, 2009 AT 12:00 PM

JSBURTON69

MEMBER
2 POSTS

The copper line doesn't look damaged. This is a newer motor and was working fine, water temp was at 190, then it started missing and had to replace a spark plug wire. While doing this a pushed the copper line against the header and didn't realize it.
Now it goes up to 230 before I see the thermostat cycle and bring the temp back to 190. I've changed the thermostat with no change. It's a new 4 core radiator.

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Monday, December 14th, 2009 AT 8:23 AM

DR LOOT

MECHANIC
2,311 POSTS

If you are running a cheap gauge It may not be reading correctly, You are going to have to go to harbor freight and purchase your self a infrared temperature gun. They costs about $25, once you have that, you can point it on the engine, you can point it on the radiator and the hoses, thermostat housing to determine Exactly what is the temperature and what Everything is running at we will also know if your gauge is correct. Let me know what happens when you're done.

Was this

answer

helpful?

Yes

No

Monday, December 14th, 2009 AT 7:21 PM