blownmiata

There is a water line that is supposed to be hooked up from the radiator to the bottom of the throttle body. I assume it is to warm the throttle body? How necessary is it? To hook this into my radiator would be a big PITA.

Cam72aro

iTrader: (28)

Not necessary. Its a throttle body heater. Makes the intake air charge warmer. Take it off. It actually hurts power a small amount.

TA-Swede

iTrader: (4)

Ditto on it not being needed. (Mine is disconnected)

However, I can't help but to wonder why it's there in the first place. I can't see that it does anything for emissions, so my next guess would be that it helps for those with cars in colder climates...

martinsw

iTrader: (3)

Isn't the setup that the heads both have steam vents at their tops - hard lined together, then through throttle body, into radiator? Purpose is to get air out of the coolant system. Do not need to go through throttle body (also understand there for cold climate cars), but should route the two head steam lines back into coolant system somewhere (recall I ran mine to an adapter in one of the heater lines).

I think I have heard some just cap them off and works for them ....

NemeSS

iTrader: (127)

cap of the lines or cut them off for cleaner look

bczee

iTrader: (12)

As Cam72aro stated. Not really needed, unless you use the car as a DD in the winter or Cold climates.. Then it might be of some advantage... Quicker Warm up.

G-Body

iTrader: (4)

You can bypass the TB, the coolant line only goes through the TB to warm it up in cold weather for better driveability/emissions.

You should still connect a line from the steam ports on the heads to the radiator. Those ports are there to bleed any air out of the tops of the heads. Some people say that you can get away with capping them off and just bleeding them when you fill the engine with coolant.. but if you run it like that and an air bubble gets in the engine it could get trapped at the top of the heads and create an air pocket/hotspot

blownmiata

I thought about routing the steam lines to the top of the radiator overflow reservoir - would that work, or would there be too much pressure bleeding off?

G-Body

iTrader: (4)

You cannot run it to the overflow tank unless it is a pressurized tank. If it is not it will continue to fill the overflow tank until it empties the coolant out of the radiator.

blownmiata

yeah, thats what I was afraid of. Guess I will tap the top of the water pump. Thanks for the help!

50adrod

iTrader: (1)

there is lots of talk about air or steam in the system. if it is properly filled where is the air comming from? I have a snap on tool that actually pulls the cooling system into a vacuum and then fills it to avoid any air pockets in the engine. wouldn't that work?

Stu Cool

iTrader: (13)

I gotta figure the GM engineers had a reason for putting the lines for steam release in there. They generally don't spend production time and money on things that are not needed. My thought is you are taking a risk if you block them.

Pat

the_merv

iTrader: (88)

Where the steam is coming from is the fact that some of the Coolant will boil in the top of the Heads, it just does. That steam rises and goes through the lines, and it condenses pretty much in the lines and turns back to Coolant. As far as air goes, anything can happen.

RE AND CHERYL

iTrader: (31)

I wouldn't do that. Best bet would be to have a nipple soldered into the radiator (assuming it not a plastic radiator) just below the radiator cap. Any air/steam that gets trapped needs needs to ge to the highest point in the cooling system. Tapping the top of the water pump will try to force water in the heads instead of letting trapped air vent. The reason for these is the same as the reason GM drilled steam holes in the heads of the 70s SB 400s. with heads with the proper holes drilled in them a street driven 400 would overheat everytime.

Re'

Stu Cool

iTrader: (13)

GM actually plumbed some trucks into the heater hose near the water pump so it does not need to be plumbed in that high. Water pump connection works fine, I have mine on top, have seen others done on the front of the pump. Of course, different swaps have different needs.

Pat

tails8

iTrader: (7)

Do a search here. There's been plenty of posts on where to put the steam line. Either drill and tap the top of the WP, or put a provision on the radiator. I had a spot in my afco radiator so I just screwed in a nipple and attached the hose..

Tails

Pop N Wood

iTrader: (1)

The fact is a lot of people have blocked the vents without any of the problems everyone else is guessing at.

I unbolted one to let the air out while filling the cooling system. Took forever otherwise.

ryanvv355

iTrader: (17)

The reason the vent is there is to prevent icing of the throttle blade and the TB bore in cold climates. Its similar to the leading edges of aircraft wings having high temperature engine exhaust running through them.

I drilled a hole in the water neck (truck water pump) and cut the barb off another crossover. I had the barb welded to the water neck, it works great and looks real clean

50adrod

iTrader: (1)

I have a 5.3 also and was looking at the water neck as a possible place to locate it. got any pics? did they weld or braze the fitting to the neck?

ryanvv355

iTrader: (17)

https://ls1tech.com/forums/conversio...cutlass-6.html

Post #115