steam vent lines gonig to throttlebody ?
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From: North Texas
steam vent lines gonig to throttlebody ? Not sure what Gen version LS engine I have that came out of a 2003 Tahoe (5.3L) but I'm trying to figure out the steam venting needs while installing this engine in a older 50's vintage vehicle. It would seem that the two existing taps (on frt of engine) with a common tube connecting them from both the left and right banks on engine block have a rubber hose coming off a tee on the driver side bank fitting which goes up and over into the bottom of throttlebody, and it appears to come back out of the throttlebody with rubber hose which may have went into some other component (i'd think the radiator or fill tank or something). Was this possibly the factory version of the steam vent setup ? And if it was, is this rubber hose exiting the throttlebody one that I can route to some lower pressure point of the cooling system to solve my steam venting needs ? Or is the hose exiting the throttebody NOT intended for this purpose ? My newer vintage radiator does not have a provision for such a connection.
Thread Starter
Teching In
Joined: Nov 2008
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From: North Texas
It's my understanding that what's called steam venting is another phrase for removal of air trapped in engine block and heads which is usually there when filling the cooling system. Isn't the line I described initially (the one coming from the two block fittings and thru throttlebody) providing this need ?
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The original came from the "steam" tubes to the TB, then out of the TB to the overflow tank. What you describe sounds like the factory parts for that system.
In the trucks there's fluid circulating through there all the time. It's not really "steam" under normal operation.
I've seen where people connect that into the top rad hose somehow; usually by tapping into the rad hose fitting in the WP. That's when using the truck WP with the tall hose fitting. Since that's a direct connection from the hot side to the cold (aka "bypass") you'd want to keep the connection somewhat restricted.
Wouldn't be hard AT ALL to add it to any rad that has a cap... drill a hole up near the top where you can reach in down the cap hole, put in a screw-in fitting. Sooooper eeeeezy. You could even convert it to braided-stainless fittings & lines, rather than rubber hose. 4-corner "steam" even. There's kits for doing that, such as from Trick Flow, then all you'd have to do is change the hose barb they supply for hooking up to the factory rubber hose, to a 4-AN fitting (or 3? can't recall... whichever size it is) and put that size on the rad. Would even look fairly good if done in a sanitary fashion.
In the trucks there's fluid circulating through there all the time. It's not really "steam" under normal operation.
I've seen where people connect that into the top rad hose somehow; usually by tapping into the rad hose fitting in the WP. That's when using the truck WP with the tall hose fitting. Since that's a direct connection from the hot side to the cold (aka "bypass") you'd want to keep the connection somewhat restricted.
Wouldn't be hard AT ALL to add it to any rad that has a cap... drill a hole up near the top where you can reach in down the cap hole, put in a screw-in fitting. Sooooper eeeeezy. You could even convert it to braided-stainless fittings & lines, rather than rubber hose. 4-corner "steam" even. There's kits for doing that, such as from Trick Flow, then all you'd have to do is change the hose barb they supply for hooking up to the factory rubber hose, to a 4-AN fitting (or 3? can't recall... whichever size it is) and put that size on the rad. Would even look fairly good if done in a sanitary fashion.
This is a 2002 Suburban engine that I converted to a four corner seam vent system...I plumbed it into the top of the water pump. This is in my 72 Greenbrier A-body wagon. Works great.
