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Discussion Starter #1
Ok guys just got a new long block 400 and the thing runs HOT! Is this just because it is new or something? I already have a griffin thermal product aluminum radiator and I'm seeing around 210-220.

Now i don't have a fan shroud and i heard that would help immensely. I plan on getting one from summit.

My question is should i get just a fan shroud to use with my flex fan i currently have or should i get an electric fan that already comes with a shroud with it and use that plus my mechanical belt driven fan.
 

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Ok guys just got a new long block 400 and the thing runs HOT! Is this just because it is new or something? I already have a griffin thermal product aluminum radiator and I'm seeing around 210-220.

Now i don't have a fan shroud and i heard that would help immensely. I plan on getting one from summit.

My question is should i get just a fan shroud to use with my flex fan i currently have or should i get an electric fan that already comes with a shroud with it and use that plus my mechanical belt driven fan.
Go to the junkyard

88-93 taurus (3800/3.8L ONLY)...

Take the fan out.

Install fan in your car.

Chunk mechanical fan. All it does is rob power:yes: The taurus fan on LOW runs the capacity of some Jeg's dual fans!:eek:
 

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Do the heads have steam holes?Is the thermostat opening?

What thermostat is in it?Is the fan pulling air towards the motor?
 

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Discussion Starter #4
Ok fan is blowing air towards the engine. That I'm sure of. The engine is a rebuilt long block so it should have steam holes drilled. Now that you mention about my thermostat i know its stupid but i couldn't remember which way was up. It might not be letting the water bypass.
 

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When is it running 210-220? If its at an idle a shroud or electric fan might help. If its while cruising, I dont think either will help. I would check the thermostat and burp the system like others have suggested if thats the case.

-Dan
 

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Discussion Starter #8
Well I know for sure i do not quite have the timing down. I'm trying to research on how to set it.

My harmonic balancer has marks from 0 to 30 and then my tab on the timing cover has a (before) 4-0 and an (after) 0-4.

At 1000 RPM's i lined up 13 deg. on the harmonic balancer to 0 on the timing indicator. Am I in the ballpark?
 

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I have the same problem with the same engine. More or less at the same temp as yours. I have dual electric fans w/ a shroud. I don't know what could be causing it.

On mine it happens while running, not stopped.

I wonder if I have 350 heads instead of 400. Maybe I'm missing the steam holes?

Also do you think me not running a thermostat could be causing it? MAybe the waters flowing too fast.


Sorry for highjackin

Hope you figure it out.


Miguel
 

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I ran a 421 last year, just an overgrown 400 with a stock radiator and a small electric fan and water pump. Overheating was only a minor problem when cruising the highway at 4000 rpm for extended times. If I had a good clutch fan with a SHROUD! there wouldn't be any issues at all. Oh......my steam holes are plugged.

The simple and easy thing to do is get a shroud on there. It may not solve all your problem but it will be a drastic improvement.
 

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My 400 sb also ran hot.

Get the timing right, then move on to other possible solutions.

Tarus fan is a good idea. Also "cooling components" makes a good one.

I opened up the back side of my water pump and installed a round plate to help with water flow, or you can buy high flow pumps.

Alum radiators have helped me the best. Two core with long internal tubes, 1 to 1 1/4, seem best.

If its OK at low speeds but heats up on the highway, then look at the air flow through the radiator.
 

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No heating problems here with a 408. 4 core Desert Cooler radiator, 2200 cfm fan. Use straight water and Water Wetter. 185 all day long! 170 when cruising.:D:yes:
 

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Well I know for sure i do not quite have the timing down. I'm trying to research on how to set it.

My harmonic balancer has marks from 0 to 30 and then my tab on the timing cover has a (before) 4-0 and an (after) 0-4.

At 1000 RPM's i lined up 13 deg. on the harmonic balancer to 0 on the timing indicator. Am I in the ballpark?
Id say this is in the ballpark...but try setting your timing at around 10-12 at 700 rpm. At 1000 rpm your distributor is advancing...and depending on the curve it could be a little or a lot....??
 

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Discussion Starter #15
Ok guys well I've looked over the issue and this is what I've decided to do.

First I'm going to move my transmission cooler away from the rad as it is restricting airflow. Second I'm going to place dual 10 inch fans on the front of the radiator that will only come on when it goes past 200. This will push air through the rad. Third I'm going to take off the mechanical fan and place THIS instead on the inside that will pull the air. It comes with a shroud and this is the biggest i can go on my rad.

My question is since I'm going to have both fans on the front and a fan on the back of the rad would i need to match the CFM's of both so the fans will not be restricting each other?
 

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Also do you think me not running a thermostat could be causing it? MAybe the waters flowing too fast.
I've always understood that no thermostat will make the water flow too fast. I believe you should cut the middle out of the thermostat and install the remainder which now looks like a big washer.
 

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Overheating because the "Water's flowing too fast" is a myth spread by internet parrots. It goes against the laws of thermodyamics. Ask anyone with a boat that uses lake water for cooling. They need to regulate flow so the engine doesn't get too cold.
Overheating is caused by a thermal imbalance. The engine generates X amount of excess heat and the radiator must be able to shed the same amount of heat.
At idle there must be sufficient cool airflow through the radiator core to carry this heat away. At highway speeds the pressure is greater in front of the core to push air through but when a vehicle is stopped the air pressure is equal on both sides and air does not flow.

A fan without a shroud is moving air but probably not much through the core. The air is being pulled from the engine compartment. The shroud seals off all paths except the one through the core. The fan evacuates air from the shroud creating a low pressure area behind the core. The higher ambient pressure in front of the core pushes the air through the core.

The way to check is see if a dollar bill will stick to the core at idle. If not then there isn't sufficient air flow.

I wouldn't have pusher and puller fans. If a proper fan and shroud doesn't cool then maybe your radiator has insufficient cooling capacity.
 

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Overheating because the "Water's flowing too fast" is a myth spread by internet parrots. It goes against the laws of thermodyamics. Ask anyone with a boat that uses lake water for cooling. They need to regulate flow so the engine doesn't get too cold.
Overheating is caused by a thermal imbalance. The engine generates X amount of excess heat and the radiator must be able to shed the same amount of heat.
At idle there must be sufficient cool airflow through the radiator core to carry this heat away. At highway speeds the pressure is greater in front of the core to push air through but when a vehicle is stopped the air pressure is equal on both sides and air does not flow.

A fan without a shroud is moving air but probably not much through the core. The air is being pulled from the engine compartment. The shroud seals off all paths except the one through the core. The fan evacuates air from the shroud creating a low pressure area behind the core. The higher ambient pressure in front of the core pushes the air through the core.

The way to check is see if a dollar bill will stick to the core at idle. If not then there isn't sufficient air flow.

I wouldn't have pusher and puller fans. If a proper fan and shroud doesn't cool then maybe your radiator has insufficient cooling capacity.
X2

Check the timing, pulley sizes and all the other hot engine gremlins that have been discussed many times. An adequate size rad with a fan(mechanical or clutch) along with a shroud is all almost any engine needs. If you want an electric fan then the Taurus/Lincoln one is a good choice. I tried a Black Magic fan on my 427 sm. blk. and it just wasn't enough for it. Went with a shroud and fan and never bother to watch the temp. gauge because it's so effiecent.
 

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The Taurus or Lincoln Mk.8 fan will move more air than all 3 of the others combined, and won't block the flow thru the radiator either.
 
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