C3 Vette Registry - The Best Resource on the Net for C3 Vettes! C3 Vette
Forums -> C3 Cooling and Heating Systems
Not Logged In! Login or Register!  Users Online: 21 / Help 
Features  Find C3 Parts on ebay in only 2 or 3 clicks!  | Add YOUR C3 to the Registry

Supporting Vendors
Bair's Corvettes
VetteBookStore.com
Mid America Motorworks
CorvetteClothing.com
Volunteer Vette Products

C3 of the Month
None Current
Enter Yours Today!
Online C3 Show
13
C3s are Registered

Vanity Plates
75STNGRY
kaz1961
Featured Links
Chevrolet Corvette Restoration Guide


Buy Now
Corvette 50th Anniversary
Corvette 50th Anniversary


Chevrolet Corvette: 1968 thru 1982, All V8 models (Haynes Manuals) (Paperback)
Chevrolet Corvette: 1968 thru 1982, All V8 models (Haynes Manuals) (Paperback)


Corvette: America's Sports Car Yesterday, Today, Tomorrow (Hardcover)
Corvette: America's Sports Car Yesterday, Today, Tomorrow (Hardcover)


Corvette Masterpieces: Dream Cars You'd Love to Own (Hardcover)
Corvette Masterpieces: Dream Cars You'd Love to Own (Hardcover)



| Hide Signatures and Profile Pics

 New Topic New Topic Post Reply Reply New Poll New Poll Search     Search Page [1]  
6/6/16 11:01pm - Original Message: 'Cooling issues in the 90+ temps'
apesa63
Former Member
- Send Private Message


Hillsboro, OR - USA

Vette(s):
1975 L48 4sp. Coupe... Rebuilt Motor

Joined: 7/20/2015
Posts: 44
History:
I bought this car 3 years ago with a March pulley setup with two 4 groove belts, one running the water pump and alternator and the other running the power steering pump. The PO had removed the fan and clutch and added a Hayden 14" electric fan in the middle of the radiator. This setup used to work ok in the heat, but since I swapped heads with bigger valves and a new cam I am getting really hot in the higher temps above 85. If I am sitting in traffic in heat over 85+ I will reach 230+ quickly. I have resorted to running the heater at high to keep it below 210.. This was not the case before  the head / cam swap. I have good clean coolant in the radiator and overflow and the cooling system seems to be working as it should. The only new item in the cooling mix is a new thermostat since the old one was sticking. I replaced it with a 190* thermo from Napa. I know it can't be the thermo, unless it is flowing less coolant. But that does not seem like it would be the issue.

Currently the electric fan only covers a 14" diameter space on the  radiator. The radiator looks original so I could go with a DeWitt and electric fans, but I would like to hear what other have done.

This is a kinda non stock 350 ( Stock short block L48 with 1094 Felrpo Head gaskets) with Edelbrock intake and 1406 carb and an MSD Dual spark ignition/6AL CDI and an under the hood Triangle Edelbrok intake.. so it is getting hot air from under the hood. Nothing too big to cool efficiently and run low octane gas. Engine runs excellent and never doesn't start on the first click. 

  1. I am thinking of either removing the thermostat in the summer. 
  2. Or replacing the radiator with an aftermarket DeWitt or similar
  3. or replacing the 14" hayden fan with a dual 13" that has a small shroud that covers the entire radiator. 
Just looking for opinions and facts.. Usually get great advice here.
Thanks,
Pat



____________________________________
Daytona Yellow '75 350 Muncie 4 spd
'73 454 on the engine stand.


 Reply Reply  Quote Reply w/Quote
 
Support C3VR!
Suport our advertisers
6/7/16 1:47am - Reply: 'Re: Cooling issues in the 90+ temps'
73shark
Standard Member
- Send Private Message


Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.

Joined: 7/9/2003
Posts: 382
Could be a bad thermostat and can check by placing in boiling water and it should fully open. Also can run without the tstat and it shouldn't even warm up. If it still runs hot, it's not the tstat.

____________________________________

1973 L-82 4 spd

 Reply Reply  Quote Reply w/Quote
6/7/16 8:36am - Reply: 'Re: Cooling issues in the 90+ temps'
johnu
Standard Member
- Send Private Message


Eagan, MN - USA

Vette(s):
1981 Corvette Two-Tone Claret color, 4 spd, C7 Vert

Joined: 5/23/2007
Posts: 504
Try some "water wetter" in with your coolant.

____________________________________
      Only 23 years together
 Reply Reply  Quote Reply w/Quote
6/7/16 12:44pm - Reply: 'Re: Cooling issues in the 90+ temps'
Adams' Apple Lifetime Member
Lifetime Member
Moderator
- Send Private Message


Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 19449
Pat, check your ignition timing....you may need a wee bit more advance. Retarded iggy timing will make the engine run hotter than it should.
How confident are in in your temp gauge? Most electric gauges aren't all that accurate. 230*+ temps should have that thing puking the coolant out once you turn the engine off. If you can, try comparing the gauge temp to actual engine temp with an infrared temp gun....see if the engine is actually getting that hot.

Running with no t-stat at all will work as a test, but it's not good for continued driving. The t-stat does more than try to regulate coolant temps...it also regulates coolant flow thru the raditator. If the coolant flows thru the rad too fast, it won't have time to actually transfer coolant heat to the air. No t-stat can also cause leaks and possibly breaks/cracks in the rad, with the coolant gushing right out of the engine into the hose with no restriction at all. If you don't want to run with a t-sat all summer, then get your old t-stat, and cut the center tower part(with the "pill") out, and then reinstall just the outer part, to use as a restrictor.

Of course, all of this is assuming the rad is clean inside and out, and the seals for the shroud are in place. Also, since you mentioned the aftermarket pulleys, do you know if they slow down the water pump speed? That could be an issue, too. Approve

____________________________________
Joel Adams
C3VR Lifetime Member #56    
My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
 Reply Reply  Quote Reply w/Quote
6/7/16 7:40pm - Reply: 'Re: Cooling issues in the 90+ temps'
apesa63
Former Member
- Send Private Message


Hillsboro, OR - USA

Vette(s):
1975 L48 4sp. Coupe... Rebuilt Motor

Joined: 7/20/2015
Posts: 44
Thanks to all for the info. I am going to revisit the timing in a few, it was at 36* at 3k rpm when I finished the cam/heads install. I am also thinking of adding a bottle of water wetter since it looks like a no brainer at $12.00.. The radiator looks stock and was working fine in last summers heat and traffic, but not exactly sure of its condition. The last thing I want to do is open the cooling system to swap t-stats. Wasn't really wanting to run without one, but if I have to visit the t-stat I would likely buy a new high flow 180*. I'm not sure if the March pulleys are underdriven but if someone has the diameter of the stock crank pulley and water pump pulley I could figure it out..

As for the shroud.. It never had one when I got the car but the PO offered it to me but it was cracked in two pieces so I did not take it. But it's been a few years and the only time it went above 210 was when the coolant was low. Never thought I would need a shroud since the electric fan is mounted directly to the radiator and not on the motor where it would likely count on the shroud to draft air through the radiator. I have also seen several older 60's and 70's cars at shows without a shroud when using electric fans.. And yes the fan runs when the engine comes up to temps.

I have a IR thermo that I will use later today as the stock water temp gauge is factory and only has three numbers 100, 200 and 280.. I mentioned 230* because it did puke a small amount of coolant out when shut off but nothing major

On Edit: 
I added 3* of advance and water wetter and im going to take it out later in the 90+ temps we have and see what she does.. This weekend I am going to make an aluminum fan shroud for this Hayden 14 inch fan so that it is sitting about 3/4 inch off the radiator and will allow more of the radiator to draft air while sitting in traffic. At speeds its not an issue. I already made a cardboard cutout to make sure it will fit and I have a 20" finger brake to get the bends nice and neat. Shouldn't take too long, maybe half a day's work. I am thinking that should make all the difference in the world. Just wondering why this is showing up now and not when I first got this car.

Thanks again to all for the help..
Pat





|UPDATED|6/7/2016 4:40:46 PM (AZT)|/UPDATED|


____________________________________
Daytona Yellow '75 350 Muncie 4 spd
'73 454 on the engine stand.


 Reply Reply  Quote Reply w/Quote
6/13/16 10:14am - Reply: 'Re: Cooling issues in the 90+ temps'
69BBConv Lifetime Member
Lifetime Member
- Send Private Message


Cincinnati, OH - USA

Vette(s):
1969 convertible 427/390 5 speed triple black with L-88 hood; 2013 Grand Sport Coupe, manual, Night Race Blue

Joined: 12/17/2003
Posts: 64
The electric fan cannot do its job without a shroud. You need to direct the air through the radiator for it to work properly.
 
I installed a Dewitt aluminum radiator and dual fans on my '69 427. The fans have a full shroud. The fans turn on at 185 degrees. The water temp never exceeds 200. Since you are not concerned about originality, electric fan(s) with a full shroud are the way to go.


____________________________________
Mark


(click on image for larger view!)
 Reply Reply  Quote Reply w/Quote
6/23/16 1:03pm - Reply: 'Re: Cooling issues in the 90+ temps'
wetvet
Standard Member
- Send Private Message


Lake Oswego, OR - USA

Vette(s):
1972 Steel Cities Gray T Top. Original Owner, Original Paint and Interior. The running gear has been rebuilt after 240,000 miles.

Joined: 10/17/2003
Posts: 540
johnu said: Try some "water wetter" in with your coolant.

Yes, The Water Wetter really works.
I just flushed my coolant system, and added the water wetter to
my 50/50 Prestone/Distilled water mix. what a difference.



____________________________________

(click to see a larger image)


"It Takes A Little Longer To Do It Right"
"It Takes A Lot Longer To Do It Again"
 Reply Reply  Quote Reply w/Quote
 New Topic New Topic Post Reply Reply New Poll New Poll Search     Search Page [1]  
 Forums -> C3 Cooling and Heating Systems
(Moderator: Adam Wartell, Norsky, Adams' Apple)
 

 
Official C3 Vette Registry Community:
Home | Forums | Email | Who's Online | Clubs | Events | Member Stats

Other Official C3 Vette Registry Areas:
Members | Research | Shop | My Account | About C3VR
 

Corvette is a registered trademark of the General Motors Corporation(GM) & Chevrolet Motor Division. Vette Registries, LLC is responsible for all site content (except for member submitted content or where otherwise noted) and does not claim or imply that Chevrolet or GM is responsible for Official C3 Vette Registry content. Vette Registries, LLC is independent from GM and is not affiliated with, sponsored or supported by GM.  Copyright/trademark/sales mark infringements are not intended, or implied and are in fact used to support GM, Chevrolet and Corvette

Official C3 Vette Registry content is Copyright 2001-2017, Vette Registries, LLC. Content may not be reused without written consent. All Rights Reserved. NS

Corvette (Vette) Model Years on this site: 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 30