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7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
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General, the overheating was present before I switched to the electric fan/shroud combo, the water pump is a new Motorcraft one. The fans are only on or off there isn't high speed, the description states they flow 2300cfm, I'm assuming that's combined? I'm going to change my settings on the Holley to have both fans on at 190 and see if that makes a difference.
What would cause the lower hose to collapse?
No spring in the lower hose and the suction of the water pump can lead to the hose collapsing, especially at high RPM.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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The guy t
The guy that wrote that article is incorrect. Under vacuum all the hoses collapse...not just the lower. When the thermostat is closed and the engine is revved the lower hose can collapse without the spring. The thermostat is the greatest restriction in a healthy system. Have you seen how small of a surface area they have ?

We use Airlift coolant fill systems every day. My car had a brand new 3 row radiator but the lower hose would collapse and cause a flow issue. This is stated from experience, not a theory.

Never tried it without a thermostat.
 

fasterthangas

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The guy t

The guy that wrote that article is incorrect. Under vacuum all the hoses collapse...not just the lower. When the thermostat is closed and the engine is revved the lower hose can collapse without the spring. The thermostat is the greatest restriction in a healthy system. Have you seen how small of a surface area they have ?

We use Airlift coolant fill systems every day. My car had a brand new 3 row radiator but the lower hose would collapse and cause a flow issue. This is stated from experience, not a theory.

Never tried it without a thermostat.
You mean like this:
20220831_110821.jpg
20220831_110841.jpg
 
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fasterthangas

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In the link I posted above; I think his wording can be construed two different ways.

"The purpose of the hose spring was to prevent collapse during the vacuum portion of the fill cycle."

Did Ford intend on keeping just the lower hose open and not collapsed to suck out that last bit of air?
I didn't post the link as fact. I posted it for the sake of conversation and insight.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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You mean like this:
20220831_110821.jpg
20220831_110841.jpg
Yup just like that. You should know better than accept that guy explanation. I get caught up in a quick search sometimes, too. The reason is because of hose collapse while the engine is running - not under vacuum during a fill. With vacuum fill all of the hoses collapse and refill with coolant. Most of the older cars had springs in the lower hoses because the rubber would get soft when hot coolant went through them. That softness and the suction from the water pump made the spring necessary.

https://www.motortrend.com/how-to/avoid-this-mistake-radiator-hose-collapse/
 

fasterthangas

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Yup just like that. You should know better than accept that guy explanation. I get caught up in a quick search sometimes, too. The reason is because of hose collapse while the engine is running - not under vacuum during a fill. With vacuum fill all of the hoses collapse and refill with coolant. Most of the older cars had springs in the lower hoses because the rubber would get soft when hot coolant went through them. That softness and the suction from the water pump made the spring necessary.

https://www.motortrend.com/how-to/avoid-this-mistake-radiator-hose-collapse/
Did you read post #47?
 
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AeroCoupe

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Filling a SBF with coolant is not hard. Drill a 1/8" hole in the perimeter of the thermostat so the air can escape the engine back into the radiator. Would look like this:

T-stat_weep_hole.jpg


To hold the hole at the top of the thermostat housing you can use a rubber band and pencil / pen / round rod like this:

Thermostat1a.jpg


Thermostat2a.jpg


Have you looked at the condenser core and made sure it is clean and not plugged? This will block air flow through the radiator and force the fan(s) to pull air around it which will make it run hot in traffic and above 50mph.

Assuming the new water pump is a reverse rotation water pump?

I will also say that the fans you have are not very good. The shroud is blocking a lot of flow which is affecting the ability to cool the motor above 50 mph speeds. A Contour fan setup is alot better than what you have.

The other thing I read was your concern with having the head gaskets oriented the correct way. It is my understanding that with a Fel-Pro gasket (it is like this on both my SBF's) you will see the corner of the gasket at the front of the motor. It will be sticking out at the bottom corner of each cylinder head.

FEL1011-2_1500a.jpg


Confirm this first so we know you got them on the correct way.
 
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Zeffer

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Thank you AeroCoupe for your input and taking the time to read my post.

This thread seems to have morphed into a debate over thermostats and rad hoses...

I will state this again for everyone, when I had an oem rad/shroud combo the car did the exact same thing. Granted the Mishimoto setup isn't as good as the Contour fan setup, it is still pulling air through well.
More and more I'm beginning to think I installed the head gaskets backwards....ugh
I'm going to check for the gasket sticking out this weekend.
I do appreciate everyone's input even though it's getting a little off topic!:)
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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I was thinking about the intake gasket when I made my earlier post. The one where i talked about snaking a wire through the intake. It is rare that an intake gasket isn't open at both ends.You could have one or both of the head gaskets backwards. Never thought of looking for a corner.
 

revhead347

Apparently my ex-husband made that mistake.
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Installing a '97 A/C condenser in my 94-95 cars as it's less fin dense thus flowing more air.

Do you have a year range on that condenser? Is a 98' condenser ok? It looks like this might help me. I figured out one of my overheating problems. In the 90s we did this really stupid thing called under drive pulleys.

Kurt
 
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fasterthangas

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Do you have a year range on that condenser? Is a 98' condenser ok? It looks like this might help me. I figured out one of my overheating problems. In the 90s we did this really stupid thing called under drive pulleys.

Kurt
I don't have a year range but be forewarned; many of the advertised units are not the correct one. There's a seller on Ebay that sells NOS '97 condensers. I just learned today that the LMR unit is supposedly the correct one. There's two versions...a piccolo style with dense fin count and the modern design with 16 fins per inch. If you Google '97 A/C condenser; you may find the NOS units on Amazon and Ebay. They are pricey though.