Need everyones opinion on why the radiator is smoking.

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Lilbud

Lilbud

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I have a 408 stroker small block.
ill start with this, its about 5 degrees fahrenheit outside and inside my little garage.
I have a 3 row aluminum radiator. I cannot get my water temp gauge to accurately work but after about 10 minutes of idling, the top of my radiator gets very hot and the top hose is warm. This all seems normal but every minute past this point the radiator starts to smoke more and more. If i turn on my two electric fans, the entire garage is completely buried in smoke and i can't see my hand in front of my face even.
The engine has shorty headers on it, the exhaust is not hooked up, so the engine is not venting outside, which may be part of the smoke but it looks to all be coming from the radiator. When i turn the engine off, the radiator continues to smoke. if i open the radiator the coolant is not even that hot. Ive tried to burp the radiator using the spill free funnel but doesn't appear to need any more coolant. I have a wet floor from the snow outside and on my boots but the radiator does not appear to be leaking. If it is, it wouldn't be very much. I will say however, i have spilled a ton of overflow coolant onto the fans and the exterior of the radiator but i doubt that could lead to all this smoke even after running it 15-30 minutes a day for the last couple days. I would imagine it would all burn off. I need some second opinions on what could possibly be wrong. The smoke does look like its coming from the entire radiator not just the top or something. Please advise on what could be happening.
 
If it is a fresh install, it could be grease burning off the radiator.
 
Any pics of the smoke show? Doesn't sound like it's been hot enuff long enuff to burn it all off, You may want to grab a ventilation fan and then give it 1-2hrs hot,......&
welcome to FABO!
 
My four-core held so much coolant in the outer fins from spillage that it took forever to "burn off". Coolant won't dissipate like plain old water will. To accelerate the process (because it was pissing me off frankly) I finally washed the exterior of the rad with clear water then air dried it with my compressor and a air wand.
 
Its a fresh motor and i am so paranoid of over heating or blowing a head gasket. I just ordered a new temp gauge since the last one was on the fritz. Without the gauge i feel i shouldnt run the motor too long. What on the motor would be a tell tale sign its over heating. Because obviously the radiator is hot but what on a motor would be a sign its getting too hot? Or maybe i will wait until the new gauge gets in.
 
Lilbud said:
Its a fresh motor and i am so paranoid of over heating or blowing a head gasket. I just ordered a new temp gauge since the last one was on the fritz. Without the gauge i feel i shouldnt run the motor too long. What on the motor would be a tell tale sign its over heating. Because obviously the radiator is hot but what on a motor would be a sign its getting too hot? Or maybe i will wait until the new gauge gets in.
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Yes you do need to get a good temp gauge.
 
Well you type above that you open the radiator & its not even getting hot... So my thoughts were ~ that its not getting hot.

Both radiator hoses hot? Meaning is it circulating coolant? My 408 takes about just under 10 minutes at idle to reach around 200 degrees - then turn on the fan. Thats is just about when the coolant in the exterior fins would smoke.
 
MichaelB. said:
Well you type above that you open the radiator & its not even getting hot... So my thoughts were ~ that its not getting hot.

Both radiator hoses hot? Meaning is it circulating coolant? My 408 takes about just under 10 minutes at idle to reach around 200 degrees - then turn on the fan. Thats is just about when the coolant in the exterior fins would smoke.
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That sounds about right, the hoses do get hot and i guess when ive felt the coolant is was hot enough for me to pull my finger out after a second or two. I guess if the engine were to be overheated it would be more scalding than that? Is there a way i can tune my carb? I feel like when its cold i need to open the screws to get it started. and then once its warmed up i need to tighten the 4 screws like half a turn. I usually keep them around 1.5 turns open. However i think my proform carb has a secondary adjuster screw near the choke that i can also turn. Its a bit much for me to fully get it tuned i think. I can hardly even turn the screws because my flat head falls out due to the motor moving so much back and forth usually.
 
Priority #1,Get rid of the exhaust outside

Two words IR and gun, that's IR-Gun
If the rad is painted, it will smoke for a while, but not an hour.
Do a pressure test, to 15 psi.If it passes,Wash the rad with clear water as suggested.
If you are concerned about overheating: remove the stat and install a restrictor, then run it up again, keeping tabs on things with the........ IR-Gun..
The rad should knock the water temperature down to about 85/90% or so between the top and bottom of the rad, With good airflow through the rad. That means with a 195 stat, the temp should drop to about 175/165. With a 160 stat, it might drop to 145/135. If you are running this beast in an enclosed space with the air temperature continually rising, and the carb sucking up hot air as well,or if you are missing a shroud,then you may not get a proper temperature drop.
With the stat removed, the temp might not come up very well, or it will take a long time.
If the engine shakes that bad, try putting some advance into it. Just yank the dizzy to where it runs smoothest. Then begin the tune.Start with the T-port sync.
 
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AJ/FormS said:
The rad should knock the water temperature down to about 85/90% or so between the top and bottom of the rad, With good airflow through the rad.
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are you (not you A/J, the OP) forcing air through the radiator?
i know you mentioned the electric fans on the radiator itself, but anything to simulate airflow like on the road?

put a few fans in front of it maybe?
 
If you can take the cap off the radiator when it's up to temp it isn't hot.
If you can stick your finger in the coolant (at all without getting burned) it isn't getting hot.
And this better be steam you are seeing and not actually smoke, because there is no way in hell it's getting hot enough to smoke and still be running with the cap off or your finger in the coolant.

Rinse that coolant out of the fins and blow them out, because coolant in the fins turns to a sticky coating that will catch all kinds of dirt and dust and make the radiator not cool as well as it could.
 
Lilbud said:
That sounds about right, the hoses do get hot and i guess when ive felt the coolant is was hot enough for me to pull my finger out after a second or two. I guess if the engine were to be overheated it would be more scalding than that? Is there a way i can tune my carb? I feel like when its cold i need to open the screws to get it started. and then once its warmed up i need to tighten the 4 screws like half a turn. I usually keep them around 1.5 turns open. However i think my proform carb has a secondary adjuster screw near the choke that i can also turn. Its a bit much for me to fully get it tuned i think. I can hardly even turn the screws because my flat head falls out due to the motor moving so much back and forth usually.
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I like what he has been saying, listen.
As to the rough idle and what you describe with the idel screws...try setting all 4 the same, like 3/4 to 1turn out from seated...the secondary blade adjustment wants to be the same as the primary as well which both should just show a crack of the idle slot. You might want to pull the carb and look underneath to see that you get both pri/sec throttle blades adjusted the same. After you bolt the carb on, start it if it will....then if not or if so, set the initial timing as to get the idle rpm around 800ish rpm and note it and get back to us. Wash off that radiator and fans real good. If it will run with the cap off and not spew out once warmed...its not overheating.
 
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