Author Topic: over heating  (Read 8311 times)

z28z11

  • Hero Member
  • *****
  • Posts: 1861
    • View Profile
Re: over heating
« Reply #15 on: August 29, 2019, 03:22:10 AM »
I've had a cracked head do this once upon a time ago - wild swings in temperature on the gauge, luckily found the problem before it really got worse. Had this happen on a late model V6, Impala motor, head gasket gave up the ghost at the edge of one cylinder - just a little bubble in the gasket, but drove me crazy until we pulled the heads off to check 'em.

Good luck, tell us what you discover -

Regards,
Steve
1968 Z28 M21/U17 BRG/W 1967 Chevy ll Nova SS 
1969 Z28 X77/M20/VE3 LeMans/W
1969 L78 X66/N66 Cortez/BVT
1969 Z11 L48/M35/C60/C06  1949 3100 5wd 235/6

pjbizjak

  • Member
  • ***
  • Posts: 304
    • View Profile
Re: over heating
« Reply #16 on: August 30, 2019, 05:52:21 PM »
OK guys first off thank you for all your feedback! With a little more basic mechanics I removed the thermostat and lower hose then did a complete flush of radiator and block three times until water stayed clear and ran motor for more than 15 minutes without overheating. installed new thermostat 180* and 15# rad cap. Things seem to be normal now but I'll wait until I take the car on the road to see what happens. Oh, not sure if I have the correct temp sensor, anybody have correct part number?
once again thanks;
Pete

pjbizjak

  • Member
  • ***
  • Posts: 304
    • View Profile
Re: over heating
« Reply #17 on: August 30, 2019, 06:00:09 PM »
Todd, Yes the heads were redone new valves hardened exhaust seats, seals, springs, guides etc. block was bored to 40 over, crank cut 10/10, new J&E pistons, new bearings rings oil pump and all seals. Cam is comp cam = to original 30/30 duntov, lifters, rockers, push rods etc. Refreshed 780 cfm holley 1111480 distributor set up by Jerry mcNeish.

firstgenaddict

  • Hero Member
  • *****
  • Posts: 2882
  • caretaker of 1971 LT1's 11130 & 21783
    • View Profile
    • Groome Family Automobiles
Re: over heating
« Reply #18 on: September 03, 2019, 02:42:30 AM »
When the car is at operating temp and you cut it off... what does the fan do?
Does it stop almost immediately?
Does it continue to spin?
A PROPER FUNCTIONING FAN CLUTCH WILL NEARLY STOP THE FAN IMMEDIATELY WHEN THE ENGINE IS KILLED (less than a single rotation) if it continues to spin it is not drawing enough air, I thought mine was ok until it was rebuilt... it's like a tornado now!
James
Collectin' Camaro's since "Only Rednecks drove them"
Current caretaker of 1971 LT1's - 11130 and 21783 Check out the Black 69 RS/Z28 45k mile Survivor and the Lemans Blue 69 Z 10D frame off...
https://plus.google.com/photos/112392262205377424364/albums?banner=pwa