Radiator overheating already
 

Sooo it looks like my cheap $125 aluminum radiator purchase on ebay was not sucha great deal. The cap says Champion on it. Its a champ at overheating alright.

Currently I am running a super cool long water pump with a 16" electric fan with a Flex-a-lite 31165 Variable Speed Control. The puller fan is mounted to a perfectly fitting shroud. 50/50 water/antifreeze mix. The ebay radiator returns on the top in the middle and exits on the lower passenger side. I am also running a overflow tank.

Last weekend I drove the truck around 100 miles on the freeway and local streets, outside temp was 96. When I got back home the truck was hot and pissing out the overflow tank. (I don't have my temp gauge hooked up, I know this needs to be installed. :cuss: ). When it cooled down it took almost 3 gallons of water to fill it back up. NOT GOOD...

To further complicate things I have ordered my vintage air kit and will be installing in the next few weeks. I have to go to a different pulley setup to drive the compresser. This new pulley setup will enable me to use a mechanical fan which I am strongly considering.

Should I switch to the mechanical fan and shroud before **** canning the ebay radiator?

Also any thoughts on this radiator from Speedway?

As always thanks for helping out.

Re: Radiator overheating already
 

Did you make sure all the air was out of the cooling system?
Did the thermostat stick?
Run some heat and cool cycles and do NOT let the overflow tank see the bottom, keep it full.
You may have had a air lock and did not get enough coolant in the system

Re: Radiator overheating already
 

and how is your electric fan wired? is it on a switch or on a temp probe? Is there any adjustment on temp kick in that you can do? First thing I would do is get the gauge working so you can see exactly how hot you're getting.

Re: Radiator overheating already
 

Another thought, I have seen the intake manifold gaskets placed backwards!
This will plug up the passage in the front of the cylinder head and not let the water circulate out of the head and back into the rad.
To check, remove the thermostat and look into both heads and see it they are open where the intake manifold meets the head in the water passage.
Just a thought!

Re: Radiator overheating already
 

Thanks for the advice guys. Will hook up the temp gauge, I am blind without it. Will remove the thermostat to check it and the gaskets. Should I install a lower range thermostat, right now I have a 180 degree?

Electric fan is wired through the controller and is adjustable. I have the "pot" adjusted to kick on at the lowest setting, not sure of the temp at that setting but the fan starts at 60% power and as it gets hotter the controller drives the fan up to 100% power.

Re: Radiator overheating already
 

your 180 degree thermo is just fine. The gauge is the first place to start. Then as you drive, you can tell when your fan is actually kicking in and how long it takes to reach it's boiling point. At least you can stop before it gets to bad by watching that gauge as you cruise

Re: Radiator overheating already
 

Many years ago I got in a hurry and installed the t-stat upside down which makes thing run a little hot too! I also check all my temp gauges and senders for accuracy. My Chevelle started running hot, turned out the gauge had decided to start reading 15 degrees hotter than the actual temp.

Re: Radiator overheating already
 

One question, is you "super cool long water pump" designed for V belts or is it for a later engine with serpentine belts? Missmatching the pump and the belts will cause the coolant to want to flow in reverse and not flow much at all. I'd make positive that I had the correct pump for the belt setup you have.

You may be correct on those aluminum radiators as some guys haven't had a lot of luck with them but it sounds strange to get that hot and puke that much coolant without being stuck in traffic or pulling a heck of a load.

Re: Radiator overheating already
 

+1 verify it's not a reverse rotation pump. Recheck the basics, Aluminum radiators generally are not the culprit.

Re: Radiator overheating already
 

I run 195F T-stat to minimize engine wear based on a study in one of my books. I never understood logic of colder T-stat swap for overheat issue.

I switched my car to electric fan and it worked fine except when relay failed.
Later I installed a mechanical to help reduce underhood temp spikes in an effort to help preserve engine and header finish.
Plus I'm not really a fan of elec fan sound.

Re: Radiator overheating already
 

If you have one of the chrome overflow tanks, it probably doesn't hold enough for the capacity of the radiator in an iffy situation. You don't have to get on the road to test it. Let it run in the driveway until the fan comes on then check the gauge. The upper hose should be hot. That means the T stat opened and circulation is happening. THEN shut it off, let it cool some and open the cap, carefully, and check the coolant level in the rad. MANY times an air bubble will have burped out when the T stat opened and the level will be low. Top it off until completely full and put the cap on and start with an empty overflow tank. Drive until temp above 180 is reached. Take it back home, shut it off and wait about 5 minutes for heat soak. Then check the overflow tank.(not the radiator!) If it is not full, you can add a little for safety as what's in the tank when hot is the amount of coolant expansion you have in your system. When the truck is completely cool. Recheck the overflow. The level should have gone down to where there is only a small amount in the tank. If you have some amount in when cold and a high, but not puking out, level when hot, that is the static level your system wants. The small, cute overflow tanks can make you be very precise. On most of them you can add about 3 inches of 1/4 fuel line to the top of the tall tube inside the cap without interfering with the cap. That gives you more coolant when hot without puking it out. Sometimes that small amount will make the difference. If none of this works and it still gets hot, we need to have a discussion about good radiators and cheap radiators. I had the one for my T roadster made by a guy in north Phoenix that does street rod radiators. It cost $600, but it works now, along with getting the larger chrome overflow tank and the other things I talked about. Lots of guys here may not know about AZ summers, I do and have had the kind of problems you're having with hot rods and engine swap vehicles.

Re: Radiator overheating already
 

that's the first thing i'd fix

Re: Radiator overheating already
 

Ok a quick update. The pump is correct and designed for a vbelt. I warmed it up in the driveway and felt the tstat open and saw good flow when engine RPM was raised. I think I have found a couple issues. Firstly the damn spring for the upper radiator hose was stuffed inside the top of the radiator tank, completely out of the hose. Strange.

Second, the adjustable pot on the temp controller was not very well adjusted. I turned the pot all the way high which caused the fan to not come on. I allowed the engine to get good and hot with the cap on, but not boiling over. I then adjusted the pot on the controller to allow the fan to run at 100% power. This position seemed alot lower than I previously remembered.

Off to eat dinner, then going to install the temperature gauge. More to follow and thanks for all the suggestions.

Re: Radiator overheating already
 

Why do you have a spring in the upper rad hose?
Those are usually for the lower hose so it does not collapse under high RPM

Re: Radiator overheating already
 

Bi-pass the temp controller and see if the fan goes any faster. Does the fan power go thru the switch (sounds like it does). Might want to switch to a simple on-off and relay.

Re: Radiator overheating already
 

Ok, temp gauge is hooked up and working. Its hard to test an overheating condition at night with the cool air. I refilled the radiator and overflow per Speedbumpauto's recommendation. Just driving around the neighborhood in first gear i could only get the temps up to 190. Just to test the controller I dialed the pot to the max (should be hottest) setting with the truck idling in the driveway and the temperature crept north of 225 before the fan kicked in. At least now I have a reference for what is "hot".

It was the best fitting hose I could find locally. I have removed the spring.

OrrieG, If I bypass the controller it will run at 100% power all the time (or when switched on) which would defeat the purpose of the unit itself. It is designed to ramp the fan speed to temperature. Hopefully now with the temperature gauge working I can get this dialed in. Thanks.

Re: Radiator overheating already
 

I was just suggesting a check to make sure the fan was operating at full speed when it is supposed to, Thought was maybe all the controls and wiring were not allowing full power to the fan.

Re: Radiator overheating already
 

It was the best fitting hose I could find locally. I have removed the spring.



OrrieG, If I bypass the controller it will run at 100% power all the time (or when switched on) which would defeat the purpose of the unit itself. It is designed to ramp the fan speed to temperature. Hopefully now with the temperature gauge working I can get this dialed in. Thanks.[/QUOTE]

I prefer the 180* thermostat and I have the electric fan se t to come on at 195*
Except when the A/C is on then it is switched with the A/C..
Cycles on and off and stays around 185* +/-5*

Re: Radiator overheating already
 

I had a fan come in recently that was wired backwards in the connector. Took a while to find the problem, and almost cost my dumba$$ a finger.

Re: Radiator overheating already
 

not sure what motor your running or how many miles on it
i had a 327 with an overheating problem
the timing chain was worn out causing the timing to always be wrong
it overheated all the time. day/night/cool/hot

Re: Radiator overheating already
 

X2 with solidaxle. My street rod has 180 stat and 195 fan control but I have a manual override on the dash. My system is pretty marginal in summer due to design constraints and I find that if I override the fan on hot days, especially at stop lights, it really makes a difference. Guess I could go to a 180 fan control but I don't like the idea of the fan running all the time and, I might be the only one, but I'm very distrustful of any device that controls the speed of a fan based on temp. If it's on, it should be working....soon as the temp drops, it will turn off. I'm of the "keep it simple" group. I like my setup so well, I'm doing the same thing on the 55.

Re: Radiator overheating already
 

Ok, so drove to work this morning, outside temp was high 50's. Temperature gauge never went above 200. When I parked I noticed the overflow tube was puking fluid on the ground. My overflow is the cheap small cylinder type. I am currently shopping a larger (1 gal) recovery tank. Will try adding the tubing inside the current overflow in the mean time.

What else could cause the system to push coolant out of the system without overheating? Thanks.
Thanks.

Re: Radiator overheating already
 

Not unusual for some coolant to escape past cap; especially if radiator over filled. Something like the ideal gas law.

Re: Radiator overheating already
 

Ok sure. Let's say it was overfilled, it will puke the extra out. But even with a smaller catch can the system shouldn't continue to puke fluid if it's not overheating?
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Re: Radiator overheating already
 

You might want to replace the rad cap and make sure it has a gasket to seal it to the rad. It should be at least 14 # and for a recovery type system.