Custom Steam Vent Q's

My question is...will this really work like this???
The reason I ask is, I had a hard time getting the coolant to fill the block (I couldn't get it to fill through just filling the radiator, I had to fill it through a heater hose.)
And then when I got it running, it seemed to want to heat the heads and block fairly warm, (I let it get to about 220* before I shut it down.) but not really open the t-stat.
I apologize for the long post, just wondering if this steam line route might have anything to do with those two problems.
(EDIT: I posted this in the external LS section, but didn't get much response. thought I'd try over here.)
the vent caps are O ringed, just pull one of those off when filling the block. It helps if you jack up the front of the car at the same time. That will get all the air out without having to pull a hose.
As for the T stat, pretty safe to say the vent lines have little to nothing to do with that. What temp T stat do you have and do you have the heater hoses hooked up? 220° at the heads probably isn't enough to get a stock T stat to open.

My question is...will this really work like this???
The reason I ask is, I had a hard time getting the coolant to fill the block (I couldn't get it to fill through just filling the radiator, I had to fill it through a heater hose.)
And then when I got it running, it seemed to want to heat the heads and block fairly warm, (I let it get to about 220* before I shut it down.) but not really open the t-stat.
I apologize for the long post, just wondering if this steam line route might have anything to do with those two problems.
(EDIT: I posted this in the external LS section, but didn't get much response. thought I'd try over here.)
To properly fill the system you need to have a large funnel designed specifically for "burping" a coolant system. The funnel needs to be above the highest point in the cooling system.
Run the motor up to operating temperature with the cap off and funnel in place. Thermo will open and fluid level will rise quite a bit but won't overflow. Once you stop seeing bubbles, system should be free of air.
A surge tank is easy to add and works well if you don't have a steam port on your radiator. Or if your rad top isn't the high point in the system.
Looks like this...
Last edited by Forcefed86; Feb 26, 2014 at 01:15 PM.
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Here's a great link describing the LS cooling system.
http://www.pirate4x4.com/tech/billavista/Cooling/
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Mine exits higher than the steam ports themselves.
Actually the original steam line on the truck engines exit in the lower right hand corner of the radiator, much lower than where I have mine...I guess that's why I thought this would work...
http://www.pirate4x4.com/tech/billavista/Cooling/
Thanks...I've read almost all of Bella's stuff...he has some great articles.
This is how I ran it originally...I didn't like the way it looked.
Last edited by CattleAc; Feb 26, 2014 at 10:12 PM. Reason: Added photo

Mine exits higher than the steam ports themselves.
Actually the original steam line on the truck engines exit in the lower right hand corner of the radiator, much lower than where I have mine...I guess that's why I thought this would work...
Thanks...I've read almost all of Bella's stuff...he has some great articles.
This is how I ran it originally...I didn't like the way it looked.

Yes, it is higher, but it's on the high pressure outlet side of the pump. You want it to be on the low side inlet. Your first routing is correct.
Ok...I wasn't thinking about this correctly...high pressure on the upper pump and outlet, and left radiator tank...low pressure right side tank and lower hose...
Check out a diesel in a Dodge truck some time. They have a manual vent. Guess the Cummins engineers didn't spend enough time on the internet.
That Pirate 4x4 article makes the same mistake every other internet motor head does. They seem to think the motor is some sort of tea kettle with little steam bubbles floating up by the force of their own buoyancy. Guess fluid dynamics wasn't in their college coursework. The simple fact is if you have steam in your motor anywhere then you have other problems.
Thanks, yes...that's why I tried it that way...I'm going to leave it alone and try it this way first.
Thanks, also. I finally took the large heater hose off and used a funnel...filled right up.
Check out a diesel in a Dodge truck some time. They have a manual vent. Guess the Cummins engineers didn't spend enough time on the internet.
That Pirate 4x4 article makes the same mistake every other internet motor head does. They seem to think the motor is some sort of tea kettle with little steam bubbles floating up by the force of their own buoyancy. Guess fluid dynamics wasn't in their college coursework. The simple fact is if you have steam in your motor anywhere then you have other problems.
You got it all figured out man. Those engineers at GM must have been crazy to install the steam ports. And because several people (with no clue how the system is designed to work) did it incorrectly and the motor didn’t explode, it must be ok! What does a Cummins engine/engineer have to do with an LS motor again? Oh that’s right…. nothing. Simple fact is… you are uneducated on the topic and shouldn’t be giving out suggestions on a system you don’t understand. Just because your coolant gauge doesn’t indicate your overheating does not mean there aren’t hot spots in the cooling system. While the lack of vents or a properly operating system may not effect a mild build to the point of overheating etc... I see no reason to not have the system functioning as it was meant to. Vents are there for a reason and add to the efficiency of the cooling system. That’s why they were designed and installed in the first place!
There IS steam in a properly functional coolant system. Bubbles form on hotspots in the head passages. This is a known fact, especially on LS motors. The bubbles prevent coolant from reaching these spots unless the air bubbles(steam) have somewhere to go. The steam vents help eliminate this. The revised design blocks the aft ports to bump up the pressure in the system to help “Scrape” these steam bubbles away from hot spots in the head passages. This is all per Jamie Meyer, head of GM performance.
At any rate I prefer the way he originaly had it routed which has the steam vent high vertically and connected to the lowest pressure part of the system. This is most similar to the 4th gen Camaro setup.
Steam ports aren't necessary for the system to "work". You can block all 4, burp the system well and the cooling system will still "work fine". Thats not the point. If you have it plumbed like the first pic it's not working as it's designed to. Might as well plug it.
Here's a great link describing the LS cooling system.
http://www.pirate4x4.com/tech/billavista/Cooling/












