Cooling system questions
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 11
From: Fisher, IL
Cooling system questions
My water pump is rusted big time. Can i sand blast and paint it?
I have to check but i don't think my temp sending unit is working correctly as my engine feels hotter then what the gauge says. Gauge doesn't go above 150F. I've read that they're hard to get another one to work correctly?
My coolant looks perfect but i'm guessing it's been sitting for years. Does it go bad and should i flush and replace it?
I have to check but i don't think my temp sending unit is working correctly as my engine feels hotter then what the gauge says. Gauge doesn't go above 150F. I've read that they're hard to get another one to work correctly?
My coolant looks perfect but i'm guessing it's been sitting for years. Does it go bad and should i flush and replace it?
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 11
From: Fisher, IL
Also. In the event i eventually want to get a new radiator(current one looks pretty bad) i'm confused as to which one i need to buy.
My 1969 has an LT-1 motor that was installed and i think this radiator matches this? Here's a shot of my snapped bolts but it shows the lower tube and how it comes out the back and has the small bump on it.
Most radiators i saw came out the side...
But i can't seem to search for LT-1 radiators and get a clear picture if that's what i need.
EDIT:
Just searched DeWitts website and their products seem to have the lower tube coming out the back like mine.
Seems like only the brass ones for some reason have the tube exiting out the side of the radiator...
My 1969 has an LT-1 motor that was installed and i think this radiator matches this? Here's a shot of my snapped bolts but it shows the lower tube and how it comes out the back and has the small bump on it.
Most radiators i saw came out the side...
But i can't seem to search for LT-1 radiators and get a clear picture if that's what i need.
EDIT:
Just searched DeWitts website and their products seem to have the lower tube coming out the back like mine.
Seems like only the brass ones for some reason have the tube exiting out the side of the radiator...
Last edited by PUNISHER VETTE; Apr 30, 2010 at 09:10 PM.
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
Why don't you simply replace the water pump? Going to the trouble of blasting it and painting seems a bit counterproductive if you don't rebuild it at the same time...you have no real idea how good the impeller or the bearing is with the age on them. Buy a new aluminum pump and paint that. If you're concerned with keeping it original, then find a rebuild kit and do that before painting it.
As far as the temp sending unit goes, the only way I'm aware of to test it is to connect it to a certified correct gauge and bring the engine up to temperature. You may have a good sender but a bad gauge.
A good radiator shop can test your radiator and see if it needs a new core or if it's more cost-effective to buy a new radiator.
As far as the temp sending unit goes, the only way I'm aware of to test it is to connect it to a certified correct gauge and bring the engine up to temperature. You may have a good sender but a bad gauge.
A good radiator shop can test your radiator and see if it needs a new core or if it's more cost-effective to buy a new radiator.
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
you can somewhat verify the sender by putting it in a pot on the stove and take readings with an ohm meter.
I'll look and old thread up were the readings were published.
be right back
You can paint the pump should be no issue with that.
Neal
I'll look and old thread up were the readings were published.
be right back
You can paint the pump should be no issue with that.
Neal
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
OK here is the chart
From Willcox site :
220 degrees = 70 ohms
200 degrees = 90 ohms
160 degrees = 140 ohms
120 degrees = 250 ohms
100 degrees = 340 ohms
put the sender in a pot of water and use your wife's cooking thermometer to keep an eye on the water temp, then check the ohms on the sender and compare them to the chart.
the gauge is a simple ohm meter graduated in degrees.
Neal
From Willcox site :
220 degrees = 70 ohms
200 degrees = 90 ohms
160 degrees = 140 ohms
120 degrees = 250 ohms
100 degrees = 340 ohms
put the sender in a pot of water and use your wife's cooking thermometer to keep an eye on the water temp, then check the ohms on the sender and compare them to the chart.
the gauge is a simple ohm meter graduated in degrees.
Neal
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 11
From: Fisher, IL
Thanks Chevymans 77 that seems like very good place to start narrowing things down with this temp gauge problem.
Only thing i guess i don't understand is how to check the ohms of the sending unit as to me it just seems like a brass piece.. At a certain temp does it put out a charge of some sort?
Here's a photo that has the sending unit in question. In the photo the wire that connects to it is disconnected... The tiny thing in between the 1 and 3 plug wires right?
Only thing i guess i don't understand is how to check the ohms of the sending unit as to me it just seems like a brass piece.. At a certain temp does it put out a charge of some sort?
Here's a photo that has the sending unit in question. In the photo the wire that connects to it is disconnected... The tiny thing in between the 1 and 3 plug wires right?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
Think of the temperature sender as a "variable resistor" that changes with temperature...cause that's what it is. You can connect an ohmmeter to the output connector and to the brass body of the sender when you put it in hot water. Stick a kitchen thermometer in there with it and you can determine the sender's calibration as you go through the normal temperature range for your car (ambient through 250F).
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Thread Starter
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 11
From: Fisher, IL
I have the car jacked up pretty high right now. Should i wait till it's back to level or do they suggest draining the fluids while it's somewhat in the air?
another thing that comes to mind. They installed an LT-1 motor but never installed the LT-1 style hood. I wonder if the car gets a bit hot due to not enough air getting to the engine?
another thing that comes to mind. They installed an LT-1 motor but never installed the LT-1 style hood. I wonder if the car gets a bit hot due to not enough air getting to the engine?
Last edited by PUNISHER VETTE; May 1, 2010 at 04:45 PM.
