Pressure lines in LT1 heads?
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From: Wichita KS
Pressure lines in LT1 heads?
Hello all, I am pretty much a newbie to LT1 motors but I picked one up for my 79 malibu wagon. I am curious about the line that runs from the back of the driver side head, to the passenger, then to the front of the intake. Ive been told that it is just a pressure line, is that true? If so, is it possible that I can just run a line from one to the other and not have to have the line that comes up the intake? any info would be great, I am just trying to clean this motor up and make it less cluttered under the hood.
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Its a steam tube, just do a TB bypass and run it straight into the rad. You are going to want somewhere for the steam to escape to, just linking them together would only equalize the pressure rather than relieving it. JMHO
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From: Under my Car as usual :)
Originally posted by Aaronh
Its a steam tube, just do a TB bypass and run it straight into the rad. You are going to want somewhere for the steam to escape to, just linking them together would only equalize the pressure rather than relieving it. JMHO
Its a steam tube, just do a TB bypass and run it straight into the rad. You are going to want somewhere for the steam to escape to, just linking them together would only equalize the pressure rather than relieving it. JMHO
The LT-1 is a pressurized system and will not have any steam in it as you will need to properly bleed the air out of the coolant.
-Shannon
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From: Hell was full so they sent me to NJ
From the "Rebuilding the LT1" article, it serves BOTH functions:
EXTERNAL COOLANT LINES
There is an extra hole that goes into the water jacket on both ends of the heads. These should be plugged when they’re in the front, but left open when they’re on the back. There’ s an external coolant transfer line that connects the holes on the back side to a reservoir that vents the air and steam vapors that would be trapped in the head and cause hot spots.
There is an extra hole that goes into the water jacket on both ends of the heads. These should be plugged when they’re in the front, but left open when they’re on the back. There’ s an external coolant transfer line that connects the holes on the back side to a reservoir that vents the air and steam vapors that would be trapped in the head and cause hot spots.
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Originally posted by Injuneer
EXTERNAL COOLANT LINES
There is an extra hole that goes into the water jacket on both ends of the heads. These should be plugged when they’re in the front, but left open when they’re on the back. There’ s an external coolant transfer line that connects the holes on the back side to a reservoir that vents the air and steam vapors that would be trapped in the head and cause hot spots.
EXTERNAL COOLANT LINES
There is an extra hole that goes into the water jacket on both ends of the heads. These should be plugged when they’re in the front, but left open when they’re on the back. There’ s an external coolant transfer line that connects the holes on the back side to a reservoir that vents the air and steam vapors that would be trapped in the head and cause hot spots.
As I said, it is a steam tube, dont delete it.
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From: Hell was full so they sent me to NJ
The theory is that its heat from the EGR riser tube that causes the intake manifold oil leak. That seems to have come from one individual, who published his repair procedure at least 5 years ago. Not sure that it is a valid concern.
In any case, its not heat from the head coolant cross-over tube that is suspected of causing the intake manifold leak.
I've seen at least one case of a big shot nitrous motor grenading the #7 piston, and the thought was that its poor circulation through the back pipe that causes temperatures to be higher at the #7 and #8 cylinders, hence those are the ones that are more likely to detonate. Not sure how valid that idea is, but the guy that lost the piston is using a seperate -10AN braided S/S line from each of the rear head connections in his 1,100HP nitrous setup.
In any case, its not heat from the head coolant cross-over tube that is suspected of causing the intake manifold leak.
I've seen at least one case of a big shot nitrous motor grenading the #7 piston, and the thought was that its poor circulation through the back pipe that causes temperatures to be higher at the #7 and #8 cylinders, hence those are the ones that are more likely to detonate. Not sure how valid that idea is, but the guy that lost the piston is using a seperate -10AN braided S/S line from each of the rear head connections in his 1,100HP nitrous setup.
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Originally posted by sfriesen
I know that it isnt part of the intake, but I have been told that the line setting so close to the intake and putting off a lot of heat can cause the rear seal to leak.
I know that it isnt part of the intake, but I have been told that the line setting so close to the intake and putting off a lot of heat can cause the rear seal to leak.
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Sure, coolant does pass through it at a constant rate. It has to the passages are open to the presurized system. The point is if it wasn't there, steam would build up and not have anywhere to go, hence the steam tube.
Aaron
Aaron
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From: Little Rock, AR
Originally posted by NOMAD
I just dont understand that. If it's a steam tube, then why does mine shoot out a solid stream of coolant ?
-Shannon
I just dont understand that. If it's a steam tube, then why does mine shoot out a solid stream of coolant ?
-Shannon
If it makes you feel any better, the official term for it is "engine coolant air bleed pipe". 
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