So we pulled the ole LT1 out of my 1994 to do a refresh on her and in the back of the engine there is a coolant line that bolts into each head. I was wondering what exactly is its purpose? Does it have anything to do with the throttle body?

 

If steam develops in the heads, that is how it gets out. If I'm not mistaken, the LSX series has a steam tube too.

 

The one going from head to head is just a coolant crossover tube. It is important. The other tube you've highlighted I dont recall. Been awhile since I've had mine apart.

 

Umm, it's the same tube.

 

It is a steam pipe or also called a coolant crossover pipe. If I were you I would keep this pipe in good condition for reuse. It may not look like much but I just had to dish out $100.00 for a new one.

 

yep its the steam tube and it is extremely important... not only steam goes through it... i ran my electric water pump with the radiator cap open cause i was making sure it was completley full and alot of fluid moves through it back into the radiator so it is more of a fluid return from the heads than an actual steam pipe though i guess it would act as one under extreme conditions.

 

Vents air and steam bubbles out of the back of the heads, along with a healthy flow of coolant. I have a coolant temperature sensor in the line at the point where it turns into a rubber hose (93/94 goes directly to the radiator, 95-97 goes thru the throttle body first). There is supposed to be a vapor/liquid separator in the radiator where the line connects. Remove the system, and you will probably overheat #7 and #8.

 

Ok, like I said. It's been awhile. I just started tearing mine apart again. Amazing all the things I've forgotten in 6 years.

 

I feel ya. It's only been 4 or 5 months for me and I find myself having to double check things. I hear memory is the second thing to go.

 

Thanks guys

 

I've been thinking about replaceing that tube with a t a 90 and some brake line or rubber hose. Has anyone done it? Will it work?

 

Yes. Yes.

 

Try a "search"... I've seen photos posted by someone who used NPT fittings and braided SS line.

 

I used NPT fittings, "great white" high temp/high pressure thread paste, and some high temp coolant hose to replace mine.

Dealer wanted rediculous cash for it, but I spent between 15 and 20 bucks for the whole setup doing it myself. Did not notice any difference since you cannot measure hotspots, but it is also slightly wider diameter then the stock line so in theory should vent steam pockets and flow coolant quicker.