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thank you everyone for all your input. It's invaluable. Keep it coming!
Ok, thanks. I guess this is written permission to note some things in the engine bay.
First, the splice in the upper rad hose. This doubles the chance for a leak between the water-neck & Rad.
Throttle return spring too weak. Should always use a dual (one inside the other)
Someone chose to delete the heater hoses. Instead of plugging the hose port at the Intake with a NPT pipe plug, you have a nipple and a chunk of rubber, clamp.
Don't be standing there when that blows.
Your brake booster must have a solo / dedicated hose from the base of the carb or an Intake manifold port. The single hose is not to be shared with a transmission line, an IGN Vac Adv line, a PCV line or a vacuum line for the headlights. All those vacuum accessories have vacuum that varies up & down with different events.
The booster must have a high, steady, vacuum source, all by itself. Brake booster hose is large outside diameter, small inside dia with extra thick wall to avoid collapsing.
And last, do not let #5 plug wire touch #7 plug wire, like yours. This will cause Inductive Crossfire. A wire loom will take care of that.
Progress!!
the probe in the radiator is the temp sender to the fan controller. Yes the box it goes to is controlling your fans, make sure there is power going in.
good news that the lower hose has a spring in it
the foam was there to force air through the fan, yes replace it until you can get a better looking solution.
the sensor in the intake is for temp gauge inside the car
so is this black box the fuse I should replace? I can’t tell if it’s blow or not. There is another 25 fuse connected but that is good.
I replaced the relay box and the thermostat and still getting to over 200. Like 210-220. Fans stil not coming ok. When I pulled the thermostat off there was no fluid in the intake manifold. Is that normal?
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I would fill the engine up until the coolant is to the top. Air in your coolant is never good. If it's too much it will end up in the overflow. The relay should control the power to the fans. The 25 amp fuse is your saftey, check that to see if there's power on both sides of it. If you have power to the controller, and still no fans then you are going to need a new controller. A controller is just a temperature controlled switch...its pretty easy to troubleshoot with a meter
This probe in the fins of your Radiator is THE WORST way to control your fans! Period!
remember me saying a number of posts back that there are a number of ways to control your fans?
This is the worst possible senerio.
Your fan control sucks! Your fans suck! Your lack of sealing around the radiator sucks!
No wonder your over heating!
These cars are much more susceptible to overheating than most. Everything MUST be right. From sealing around the rad to correct ignition timing to a proper fan shroud and by all means proper fan control.
Oh, and that intake should have been full of coolant! When you remove the thermostat housing you should have made a big mess!
This probe in the fins of your Radiator is THE WORST way to control your fans! Period!
remember me saying a number of posts back that there are a number of ways to control your fans?
This is the worst possible senerio.
Your fan control sucks! Your fans suck! Your lack of sealing around the radiator sucks!
No wonder your over heating!
These cars are much more susceptible to overheating than most. Everything MUST be right. From sealing around the rad to correct ignition timing to a proper fan shroud and by all means proper fan control.
Oh, and that intake should have been full of coolant! When you remove the thermostat housing you should have made a big mess!
@4-vettes may sound grumpy, but he is 100% correct on every point.
I'd start by topping up your coolant (drill a tiny hole in the thermostat before you install it, to prevent air bubbles), top off your rad, burp the system, etc.
OK, so we are all assuming here that your running hot is related to your poor fans. Lack of decent fan control and a cooling system that isn't even full.
This is certainly a problem. But please keep in mind it may not be the only problem. None the less, this is a good place to start.
Just for giggles. Let's look at a system that does function properly. These are C5 Corvette fans. Note how the shroud covers 98 percent of the radiator cooling surface? Look down along the side of the radiator, Note how the rad is sealed completely to the support? And it is 100 percent of the way around. Including the seal to the hood so air can not go over the top. Stock location for the temp gauge sensor in left head. Late model coolant temp sensor in the intake manifold. Sending precise information of the actual coolant temp in the engine to a ECU. My fan run settings. They very rarely run with these settings. Only when going very slowly or long traffic lights.
So, good fans that have a properly designed shroud. Taking temp readings off the engine. Not in the rad.
And correct wiring from start to finish.
Lots of other factors in overheating Corvette's to consider as well.
from proper timing to that spring in the lower hose and everything inbetween.
There is a Web site called "Mad Electrical" Google them. Go to there tech pages. It's like old car wiring for dummy's. Read up on how to properly wire up your fans. Start over and do it right!
Put in some decent fans with a proper shroud. I highly recommend the C5 corvette fans. With a little trimming they fit great and a factory designed shroud works! Fill your cooling system correctly and make certain you burp out all the air.
Then see how ya go.
OK, so we are all assuming here that your running hot is related to your poor fans. Lack of decent fan control and a cooling system that isn't even full.
This is certainly a problem. But please keep in mind it may not be the only problem. None the less, this is a good place to start.
Just for giggles. Let's look at a system that does function properly. These are C5 Corvette fans. Note how the shroud covers 98 percent of the radiator cooling surface? Look down along the side of the radiator, Note how the rad is sealed completely to the support? And it is 100 percent of the way around. Including the seal to the hood so air can not go over the top. Stock location for the temp gauge sensor in left head. Late model coolant temp sensor in the intake manifold. Sending precise information of the actual coolant temp in the engine to a ECU. My fan run settings. They very rarely run with these settings. Only when going very slowly or long traffic lights.
So, good fans that have a properly designed shroud. Taking temp readings off the engine. Not in the rad.
And correct wiring from start to finish.
Lots of other factors in overheating Corvette's to consider as well.
from proper timing to that spring in the lower hose and everything inbetween.
There is a Web site called "Mad Electrical" Google them. Go to there tech pages. It's like old car wiring for dummy's. Read up on how to properly wire up your fans. Start over and do it right!
Put in some decent fans with a proper shroud. I highly recommend the C5 corvette fans. With a little trimming they fit great and a factory designed shroud works! Fill your cooling system correctly and make certain you burp out all the air.
Then see how ya go.
This probe in the fins of your Radiator is THE WORST way to control your fans! Period!
remember me saying a number of posts back that there are a number of ways to control your fans?
This is the worst possible senerio.
Your fan control sucks! Your fans suck! Your lack of sealing around the radiator sucks!
No wonder your over heating!
These cars are much more susceptible to overheating than most. Everything MUST be right. From sealing around the rad to correct ignition timing to a proper fan shroud and by all means proper fan control.
Oh, and that intake should have been full of coolant! When you remove the thermostat housing you should have made a big mess!
what type of fans should I be running? What type of fan controls should I be using?
I will check tonight if there is coolant in the intake after the new thermostat. If not I will top it off whiling drilling a hole in it as mentioned in another post.
Do tou have ramps? Or a sloped driveway? Park nose up, drill the tiny hole, fill the engine with coolant, install thermostat and hose, top off the rad and overflow tank, then run the engine. Top off the overflow as needed
I run dual Spal fans, with a 195-185 switch in the intake and two relays. You'll need a new alternator and a bunch of wiring to do this properly, which is in a bunch of threads on this Forum.
The C5 fans are a great choice, and what Ill do for my other car.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
A fan set up like that will work without the vents. The vents have to be able to close when the car isnt moving, otherwise the fans would just pull air through the vents ...air is going to travel the path of least resistance. I bought a fiberglass shroud from speedway that you would cut the holes for the fans for a custom fit and add the foam strips to. Only issue is the highway flow of air at speed has to fight the fans. Electric is far superior to mechanical, machanical is reliant on engine speed and will overheat in stop and go traffic. Theres a reason no car maker anywhere uses them anymore. Plus of you are a HP fiend then you can save 20 hp over a mechanical fan.
I upgraded to the shrouds with the rubber flaps, they work great
as for a fan controller stay away from the current pwm controllers, they dont last long, just go with a standard on off style that can control 2 fans. If you can start them at 2 different settings that is better. Check summit and speedway for universal fit setups. Dont shop amazon or FB marketplace for these items..
Last edited by Rescue Rogers; Jun 19, 2024 at 01:24 PM.
