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Discussion Starter · #1 ·
Feel kinda dumb for asking but i recently did intake manifold gaskets, i drained the coolant before hand now that i am ready to refill and bleed should i try filling the radiator first then the resevior on the fender after i start and add from there as i bleed the system?
 

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The 94 FSM says to fill the reservoir.

With most cars I leave the front on jack stands and fill as much as I can through the thermostat houseing before installing the thermostat. I use a pump or a funnel with a hose on it to fill the radiator as much as possible and then install the hose. Then I top off the reservoir.

This is a opinionated topic and there are many ways to fill and bleed.
 

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If you can fill it slowly enough with the burp valve open (hopefully your valve has a hose on it, or some way of protecting the Opti-Spark from unnecessary dribbles?) with the nose pointing a bit uphill
leave the front on jack stands
you won't need to burp it that much.

The lucky bastaduccis who have an early '94 style radiator can use the obsolesced connection on top of the radiator as another burping point.
 

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Discussion Starter · #5 ·
Yep mines a 94, i was just squeezing the upper rad hose thar goes to my water pump to burp while i had my aftermarket bleeder spout open hooked up to a clear hose running right back into my resevior
 

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Yep mines a 94, i was just squeezing the upper rad hose thar goes to my water pump to burp while i had my aftermarket bleeder spout open hooked up to a clear hose running right back into my reservior
If your radiator is an early '94 style, it has a 3rd smaller hose that is even easier to burp than the BeasstBleeder.
The early '94 style radiator remains far more useful than the early '94 style reservoir.
 

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If your radiator is an early '94 style, it has a 3rd smaller hose that is even easier to burp than the BeasstBleeder.
The early '94 style radiator remains far more useful than the early '94 style reservoir.
Are you saying this is only true for early 94 radiators that are original factory units? Or can a person buy this style of radiator?
 

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Are you saying this is only true for early 94 radiators that are original factory units?
Or can a person buy this style of radiator?
There are also some aftermarket radiators that, for reasons unknown, did not delete the 3rd hose fitting from their radiators. (NOT the ones that would be approved by ACDelco.)
So long as they do not 'update' their radiator specs, should be able to buy an early '94 style radiator.

GM REALLY should have just converted the 'obsolesced' 3rd hose fitting into a burp valve …
 

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My BeCool had that port ,and it's connected to bleed pipe/reservoir.
 

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My BeCool had that port, and it's connected to bleed pipe / reservoir.
My understanding is that with the radiator directly connected to the reservoir, winter warmups took longer, so GM deleted the connection.
 

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If an LT1 guy was " clean sheet of papering",
I wonder if they would be better served having the bleed line on the hot side of the rad.
All the self bleeding benefits, without the rad being heated with the thermostat closed.
( also to prevent what I speak of below)

My bleed is passenger side but my rad is dual pass with both hoses on the passenger side so it is hot bleed.

Now another thought which we have not talked about.
At full song hot, with the rad naturally being a restriction, I wonder if they experienced pull over of air from the surge tank ?
It is a real thing with some Fords re routing lines under TSBs.
Other cars like the Coyote I take care of has one way check valves to prevent what I am speaking of,
Pulling air into the cold side of the rad at high RPM .
 

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Not seeing how that would be since there isn't any coolant flow. The open port insures the radiator is full since the reservoir level is so much higher. Those who connect the bleed pipe to this port could easily have air inside trying to escape.
 

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As you can appreciate, coolant flows due to a pressure differential in a system.
As in the pressure on the outlet of the water pump is higher than the inlet.

Remember the old top tank rads that spit out of the rad cap when you wound them up.
Moving the cap to the lower pressure return side all but elevated that.

The surge tank is always being "pulled on" as it is directly connected to the water pump in.
The higher pressure in the heads is what causes the water and trapped air to full out of the heads, through the "steam" pipe to the surge tank.
The 94 rad bleed also , as you know ,is bleeding a small amount from the rad to the lower pressure surge tank.
What I am suggesting below , is a real phenomena on other engines.

At high pump flow, thermostat fully open, the large rad hose from pass tank to water pump inlet would be flowing enough coolant that its pressure could be less than the surge tank , with its 3/4 hose that is also sharing heater core water.
If the lower rad hose and passenger side rad tank pressure got below surge tank pressure, air would drift from tank to cold side of rad, possibly mixing with returning water.
 
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