Author Topic: 1969 Camaro Over Heating issue  (Read 1838 times)

camaroman1969

  • Member
  • ***
  • Posts: 127
    • View Profile
1969 Camaro Over Heating issue
« on: July 08, 2017, 01:24:41 AM »
Hi Guys!!  Need some direction on a 69 Camaro BB that is over-heating bad.  I found the clutch fan touching back of radiator.  Corrected this, but still is HOT. Have flow in tank that was changed out during resto.  Suspect water pump may be culprit.  What is the best way to trouble shoot this issue???  All responses would be appreciated.  Thanks!   Don

dutch

  • Member
  • ***
  • Posts: 379
  • Documented Canadian 1968 Z/28
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #1 on: July 08, 2017, 01:36:16 AM »
Will not correct it - but get an infrared heat gun to figure out just how hot it really is first!

ssl78

  • Member
  • ***
  • Posts: 37
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #2 on: July 08, 2017, 02:29:57 AM »
Does it overheat when idling or cruising.

77thor

  • Member
  • ***
  • Posts: 274
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #3 on: July 08, 2017, 01:35:37 PM »
I would start with the thermostat...
1969 Camaro SS, 350(NOM), M21, 12 Bolt Posi, 01B LOS Build
1977 Camaro, 350(LM1), M20, 10 Bolt Posi, Purchased New, (SOLD)

WorkinProgress

  • Member
  • ***
  • Posts: 79
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #4 on: July 08, 2017, 05:58:20 PM »
Is there a fan shroud in place?

                             - Warren

camaroman1969

  • Member
  • ***
  • Posts: 127
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #5 on: July 09, 2017, 01:20:28 AM »
To All....We used unfared heat gun...185-190 going in and coming out.  Orginal fan shroud in place.  Changed thermostat to a high flow one from Jegs (high perf) still no good.  Added additive to coolant to disapat some heat, no good.  removed thermostat, and still no good.  Over heats driving and idling.  We think radiator has something wrong inside.  I think with this major problem, a Harrison tank should be installed.  These repo's don't preform at all.    Additional advice welcome.  Thanks guys

Stingr69

  • Hero Member
  • *****
  • Posts: 554
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #6 on: July 09, 2017, 02:13:07 PM »
water pump impeller fell off?  you need to verify water flow. cold start car and leave cap off radiator.  watch for flow.  feel hoses to see if you have one hotter than the other.

bertfam

  • CRG Member
  • *****
  • Posts: 2991
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #7 on: July 09, 2017, 03:43:05 PM »
Quote
To All....We used unfared heat gun...185-190 going in and coming out.

185-190 is NOT overheating! In fact, the standard thermostat installed on these cars was rated at 195 degrees.

When you get to 220-230, then you're starting to get hot, but you're still not overheating. GM states in the Corvette owners manual that "Temperature gauge readings will vary with air temperature and operating conditions. During normal operation, gauge will indicate around the 210 degree mark. Hard driving, heavy traffic with stop and go, or prolonged idling in hot weather will produce a gauge reading around the 230 degree mark. Whenever the gauge reaches 250 degrees, stop engine and determine cause of overheating, or reduce speed permitting engine to cool".

This 250 degree limit applies to ALL Chevrolet engines produced in the late 1960's because they run hotter than the earlier engines. This is due to an early engineering attempt to reduce hydrocarbons, oxides of nitrogen and other byproducts of internal combustion engines (pollutants), to meet EPA requirements. Before the late 1960's, distributor vacuum advance canisters were connected to full manifold vacuum. When the vacuum advance was changed to ported vacuum, this caused the engine to run hotter, thereby burning off the excess pollutants. Well, kind of! It was a band-aid fix at best and really didn't do too much in the way of reducing pollution. But it satisfied the EPA to a certain extent until better methods (like the catalytic converter) was introduced.

If you want to put the vacuum advance BACK to full manifold vacuum (and yes, this will help with overheating), follow John's instructions in THIS THREAD. However, like I stated in my first sentence, 180-190 is NOT overheating.

Ed
Ed "Bert" Bertrand
email me!

jdv69z

  • Hero Member
  • *****
  • Posts: 1056
  • 69 RS Z/28 52E
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #8 on: July 09, 2017, 10:55:41 PM »
Yes, back in the 60's the thermostats were 180 degree, which means they opened at this temp. Today my 2010 Camaro's thermostat opens at 190 degrees. In my first car, a 57 chevy with a 327, I could watch the water temp gauge needle drop as the thermostat opened at 180. I could even tell if the thermostat was sticking by the needle movement.
Jimmy V.

camaroman1969

  • Member
  • ***
  • Posts: 127
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #9 on: July 10, 2017, 01:57:17 AM »
Stinger 69   I have flow in radiator tank.  Is a "moderate flow" normal??  Or should water pump be moving more water faster???   I guess question is, what is a good flow rate???  Also, radiator is a repo one. 

JKZ27

  • Member
  • ***
  • Posts: 471
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #10 on: July 10, 2017, 10:04:48 AM »
What is your indicator that it is overheating? Temperature gauge showing above 195 or is it pushing coolant out of the radiator cap? Did it just start doing this?
John
69 RS/SS Cortez Silver, L48 MC1
68 RS Ash/Ivy Gold 327EFI M20

68Zproject

  • Hero Member
  • *****
  • Posts: 1810
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #11 on: July 10, 2017, 03:11:11 PM »
I don't think the repros have a "fill line" on them so are you filling it too full and thinking it's overheating because fluid comes out?  If so, you need to have the level in your radiator down 2-3 inches below the cap as that is "full".
68Z28

janobyte

  • Hero Member
  • *****
  • Posts: 1209
  • Before it was called Day 2 !
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #12 on: July 10, 2017, 08:35:29 PM »
To answer your flow question, simply put, faster is not better concerning coolant flow. Time is needed to absorb heat: block and heads. Then heat disipation, through the radiator. Thermostat is a variable resistor, so to speak, which controls the coolant flow. What you are calling moderate dictates flow, which indivates its opening. How are your hoses? Bottom one will start to collapse with age, hence add restriction to flow.
68 Z/28  born with: 302, drive line, etc..

janobyte

  • Hero Member
  • *****
  • Posts: 1209
  • Before it was called Day 2 !
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #13 on: July 10, 2017, 08:38:51 PM »
And yes to all the other posts.
68 Z/28  born with: 302, drive line, etc..

maroman

  • Hero Member
  • *****
  • Posts: 606
    • View Profile
Re: 1969 Camaro Over Heating issue
« Reply #14 on: July 10, 2017, 09:24:28 PM »
I'm wondering about your comment about " 185-190 in and out." Where is in and out?
Doug  '67 RS/SS 396 auto I know the car since new