C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Cooling Problems

Thread Tools
 
Search this Thread
 
Old Mar 14, 2007 | 01:04 PM
  #1  
79corvette's Avatar
79corvette
Thread Starter
Racer
20 Year Member
 
Joined: Sep 2002
Posts: 293
Likes: 0
From: Englewood CO
Default Cooling Problems

I am having some cooling problems after installing a Mark VIII fan and a DC Controller. I think the problem might be my water pump, but I am not sure. I let the car idle to heat up and open the thermostat, eventually the fan came on but my tempeture gauge was reading above 200. I think the fan also shut off shortly after (needle above 200). When the fan was on it did not seem to have any affect on the temperture gauge (kept climbing). I shut off the engine when the needle got very close to the red. When the fan was on it did seem like it was moving a lot of air.

I figure it might be the water pump because I assume my new fan controller is working and cooling off the water in the radiator and that the water in the block is not flowing. Does this seem logical? Thanks for the help.
Reply
Old Mar 14, 2007 | 01:22 PM
  #2  
SIXFOOTER's Avatar
SIXFOOTER
Le Mans Master
Supporting Lifetime Gold
10 Year Member
 
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Default

Sounds like you might have air in the system. When you check it out next, open the radiator cap and make sure you can see fluid moving when the t-stat is open. Drilling a small hole in the t-stat is a good way to get the air to bleed out. Sounds like the controller is working if the fan cycled on and off. Where did you install the sensor?
Reply
Old Mar 14, 2007 | 01:45 PM
  #3  
79corvette's Avatar
79corvette
Thread Starter
Racer
20 Year Member
 
Joined: Sep 2002
Posts: 293
Likes: 0
From: Englewood CO
Default

I installed the sensor on the lower right side. Pretty close to the bottom outlet.
Reply
Old Mar 14, 2007 | 03:27 PM
  #4  
SIXFOOTER's Avatar
SIXFOOTER
Le Mans Master
Supporting Lifetime Gold
10 Year Member
 
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Default

Thats a good place for it. Check out the air pocket issue, my bet would be there. The T-stat is always a suspect when the temp tends to climb. Remember the temp gauge reads the temp between the center cylindars on the head, which will be the hotest part of the engine. With the fan upgrades you have done you should be good, water pumps usually leak when they fail, so if its not leaking I wouldn't suspect the pump. Replace the t-stat and drill a 1/8" hole in it to bleed off the air. Problem should go away
Reply
Old Mar 14, 2007 | 03:46 PM
  #5  
PhotoVette1's Avatar
PhotoVette1
Safety Car
 
Joined: Mar 2005
Posts: 3,503
Likes: 2
From: Raleigh NC
Default

Feel the air coming out of the fan.

Check and see if the airstream is coming straight out of the fan.

Or, does it deflect to the sides instead of straight out? If so, the radiator fins are clogged with debri (on the outside.)


Last edited by PhotoVette1; Mar 14, 2007 at 04:29 PM.
Reply
Old Mar 14, 2007 | 04:51 PM
  #6  
79corvette's Avatar
79corvette
Thread Starter
Racer
20 Year Member
 
Joined: Sep 2002
Posts: 293
Likes: 0
From: Englewood CO
Default

Thanks guys for the help. I bought a new 180 degree thermostat and drilled a coupld holes in it. I will be installing it tomorrow, got to paint some of the house tonight. The air comes straight out of the fan. The fins should be good, it is a fairly new aluminum radiator. The fan really pulls air through when it comes on full, atleast I know something is working properly lol.

Does a water pump actually go bad (as in stops flowing water) or does it just leak?

Last edited by 79corvette; Mar 14, 2007 at 04:55 PM. Reason: added question
Reply
Old Mar 14, 2007 | 04:56 PM
  #7  
chevymans 77's Avatar
chevymans 77
Melting Slicks
Supporting Gold
20 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Default

Originally Posted by 79corvette
I installed the sensor on the lower right side. Pretty close to the bottom outlet.
Why at the outlet of the radiator? Tom mounts his at the inlet; the fan should work in conjunction with the T-stat. I am not familiar with the DC controller, does it start the fan at low speed and ramp up from there. Set the fan to come on just below the T-stat temp and ramp up from there, let the radiator and T-stat do the work and than use the fan when it is needed.

Neal
Reply
Old Mar 14, 2007 | 06:49 PM
  #8  
79corvette's Avatar
79corvette
Thread Starter
Racer
20 Year Member
 
Joined: Sep 2002
Posts: 293
Likes: 0
From: Englewood CO
Default

Originally Posted by chevymans 77
Why at the outlet of the radiator? Tom mounts his at the inlet; the fan should work in conjunction with the T-stat. I am not familiar with the DC controller, does it start the fan at low speed and ramp up from there. Set the fan to come on just below the T-stat temp and ramp up from there, let the radiator and T-stat do the work and than use the fan when it is needed.

Neal
The instructions told me to place it in that area. I think it is placed there this way the fan only runs when the flow of air from driving isn't enough. The DC controller is a variable speed controller, starts slowly and varies the current. The conroller was set to hold the engine at 180 and the T-stat was 195 (the new T-stat I bought is a 180).
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-1

2027 Corvette vs The World: Every Model vs Closest Competitor

 Joe Kucinski
story-2

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
story-3

5 MOST and 5 LEAST Popular Corvette Model Years in History!

 Joe Kucinski
story-4

2027 Corvette Buyer's Guide: Everything You Need to Know!

 Joe Kucinski
story-5

10 Things C8 Corvette Owners Hate (But Won't Tell You)

 Joe Kucinski
story-6

10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

 Brett Foote
story-7

Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

 Joe Kucinski
story-8

Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

 Michael S. Palmer
story-9

5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

 Joe Kucinski
Old Mar 14, 2007 | 06:55 PM
  #9  
Ironcross's Avatar
Ironcross
Race Director
10 Year Member
 
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Default

I`m nearly 100% sure that the water pump is ok. They keep on working even when they are leaking from the shaft seal.
Reply
Old Mar 14, 2007 | 07:19 PM
  #10  
PhotoVette1's Avatar
PhotoVette1
Safety Car
 
Joined: Mar 2005
Posts: 3,503
Likes: 2
From: Raleigh NC
Default

Originally Posted by chevymans 77
Why at the outlet of the radiator? Tom mounts his at the inlet; the fan should work in conjunction with the T-stat. I am not familiar with the DC controller, does it start the fan at low speed and ramp up from there. Set the fan to come on just below the T-stat temp and ramp up from there, let the radiator and T-stat do the work and than use the fan when it is needed.

Neal
The outlet of the radiator is the correct place for the sensor for the DCC; I have his same setup.
Reply
Old Mar 14, 2007 | 10:55 PM
  #11  
SIXFOOTER's Avatar
SIXFOOTER
Le Mans Master
Supporting Lifetime Gold
10 Year Member
 
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Default

Originally Posted by Ironcross
I`m nearly 100% sure that the water pump is ok. They keep on working even when they are leaking from the shaft seal.
True story, water pumps pump and don't leak or they work and leak
Reply
Old Mar 14, 2007 | 11:22 PM
  #12  
Old Mo's Avatar
Old Mo
Advanced
10 Year Member
 
Joined: Mar 2005
Posts: 68
Likes: 0
From: Wamego Kansas
Default

Water pumps can be bad . Not supply enough flow threw the system. They are a centrifical pump and if there is too much clearance between the impeller and the housing flow will deminish. This is not an uncommon problem with rebuilt water pumps. This will usually be noticed by the engine running cool at higher rpms but heating up at lower rpms.
Reply
Old Mar 15, 2007 | 03:00 PM
  #13  
Ironcross's Avatar
Ironcross
Race Director
10 Year Member
 
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Default

Originally Posted by Old Mo
Water pumps can be bad . Not supply enough flow threw the system. They are a centrifical pump and if there is too much clearance between the impeller and the housing flow will deminish. This is not an uncommon problem with rebuilt water pumps. This will usually be noticed by the engine running cool at higher rpms but heating up at lower rpms.
I dont agree with that statement at all. We have sold hundreds of rebuilt waterpumps without any serious problems as long as properly installed. I have seen pumps with the hub broken off but those problems are normally caused with improper belt tension by DIYS`s. Even with a leaking bad hub seal all thats necessary in an emergency is to turn back the radiator cap to it`s first notch to remove the pressure and let the system go along for the ride until back to home base and repaired.
Reply

Get notified of new replies

To Cooling Problems





All times are GMT -4. The time now is 09:45 PM.

story-0
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-1
2027 Corvette vs The World: Every Model vs Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-20 17:58:41


VIEW MORE
story-2
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-3
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-4
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-5
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-6
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-7
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE
story-8
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

Slideshow: Breaking down the 2027 Grand Sport, Grand Sport X, Stingray, and LS6 V8.

By Michael S. Palmer | 2026-03-26 13:48:45


VIEW MORE
story-9
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

Slideshow: 5 reasons bad drivers crash sports cars & 5 ways to avoid a costly shame!

By Joe Kucinski | 2026-03-25 16:32:55


VIEW MORE