What to do with steam line?

[MDPotter]

I had done some research months ago on how to deal with the steam line on my engine but I'm not sure if my plan will work. I don't plan on buying a radiator that has the steam inlet and would rather not have one welded in because it will probably void the warranty. I don't quite understand what happens with the steam lines either. I bought the Dorman 47112 tee so I can tap into a heater hose line, but won't that allow hot coolant to run into the steam line? If so, is that an issue? If it's not an issue, should I tee into the return line?

I have always had this idea that the steam line was basically a vent and that it didn't have coolant running through it so it needed to have a clear outlet such as just beneath the cap on the radiator tank.

[sprint_9]

The steam line is there to help carry away any steam or air build up in the heads created from hot spots. It will have coolant flowing in it. From what Ive read is the best routing is for it to have a path to the radiator with constant coolant flow. This way any steam can be burped off with the radiator cap.

Now if I remember correctly there is something older, like a trailblazer or something that ran the steam port down by the heater hoses, I dont remember exactly where it went but it was in that area. So you would probably be ok with your plan.

I think a better alternative is tapping the back of the upper radiator hose port on the water pump and threading it for a barb. This gives it a good path to the radiator with good flow, and is nice and clean. There have been a few on here do this including myself. Here is a pic of mine.

[mongocanfly]

On my C30 I ran it into the water pump as well.....on the IH I'm running it into the top radiator hose....I think as long as it's got somewhere to go itll be ok

[MDPotter]

Thanks guys. If I end up with a radiator without a steam inlet, I'll know how to deal with it.

[bigmoe]

I heard it works better if it's routed into somewhere higher, especially to get trapped air out of an engine that's just been filled with coolant. I've seen many that have purchased a T fitting for the upper rad hose. Someone on here will respond with a pic and/or part source.

[mongocanfly]

I simply made my own

[bigmoe]

Here is the supplier I was thinking about. Jagsthatrun.com

[MDPotter]

The Jagsthatrun tees are nice, but they seem pretty expensive to me for what they are. I plan on utilizing a steam port on the radiator or getting a cheaper plastic tee for the upper hose.

[87chevy.com]

I had a stock 454 radiator, probably same fittings and everything but the size of the core. Simply connected the steam line to the radiator on the passenger below the cap. Had it that way for 7 years as a daily.

[Willie Makeit]

seems a lot of folks are hesitant to drill and tap the water pump? why is that? seems the easiest to route and to make for a cleaner looking install.

[mongocanfly]

Willie...Ive found that some water pumps are very thin walled...hard to get a good thread in it

[ls1nova71]

I've drilled and tapped the water pump before, but my only reservation about it is what to do if that water pump ever decides to crap the bed in the middle of nowhere. I usually carry tools to change one, but dont generally carry a drill and tap. But I drive my cars, so that's why I like to keep them closer to stock so I can get replacement parts easily.

[Willie Makeit]

Originally Posted by ls1nova71

I've drilled and tapped the water pump before, but my only reservation about it is what to do if that water pump ever decides to crap the bed in the middle of nowhere. I usually carry tools to change one, but dont generally carry a drill and tap. But I drive my cars, so that's why I like to keep them closer to stock so I can get replacement parts easily.

Excellent point that I never thought of.

[ls1nova71]

I know if you had to swap pumps, you could always cap the steam line off in a pinch, but I would just rather not have to mess with it. Maybe that's why I've never had to swap a pump out on a trip? And maybe I just jinxed myself? LOL!

[kipps]

Originally Posted by ls1nova71

...my only reservation about it is what to do if that water pump ever decides to crap the bed in the middle of nowhere....I drive my cars, so that's why I like to keep them closer to stock so I can get replacement parts easily.

Totally agree with this sentiment. The common replacement parts of a vehicle need to be kept stock. A goal for anyone doing a LS swap, is that the drivetrain should be as easy to service and repair as the donor vehicle would have been.

[jnickell41]

I also tapped the water pump. I also added a plastic tee that fits the heater hose to my roadside parts box. That way if the water pump has to be replaced while away, I can splice into the heater hose and have a place for the steam hose.

[skyphix]

Before I decided to just use a radiator out of an LS equipped vehicle, I was going to use this.

https://www.amazon.com/Dorman-902-99...0218488&sr=8-4


seems weird to use VW parts on a chevy truck, but beggers can't be choosers...

[prodjay10]

Wouldn’t your heater core have constant coolant flow? If I remember correctly, there is no shut off valve.

Anyone seen the four seasons version of that tee? I’m trying to find it but can’t.

[ls1nova71]

67-72 Factory air trucks have a shut off valve as do most aftermarket AC units.

[bigmoe]

This is the one I bought on Ebay that I plan to use. It will allow the coolant to always circulate but allow you to shut off the supply to the heater core. I probably won't even hook up a cable. There's many versions if you search bypass heater valve but this one was pretty inexpensive.

[sweetk30]

Originally Posted by bigmoe

This is the one I bought on Ebay that I plan to use. It will allow the coolant to always circulate but allow you to shut off the supply to the heater core. I probably won't even hook up a cable. There's many versions if you search bypass heater valve but this one was pretty inexpensive.

ebay item # or link please .

[ls1nova71]

That looks just like the heater shut off on an LLV, the small postal trucks that I work on every day. LOL!

[prodjay10]

I think I'm gonna go this route for ect/coolant temp gauge.

https://www.youtube.com/watch?v=wvfkIUpx8_o

[bigmoe]

Originally Posted by prodjay10

I think I'm gonna go this route for ect/coolant temp gauge.

https://www.youtube.com/watch?v=wvfkIUpx8_o

This looks interesting. So that sender is compatible with Gen III and IV engines?

[prodjay10]

Apparently. I ordered one along with a pigtail. I'll let you know how it goes. I did read some info about having to make sure it's the proper resistance...

The coolant hose adapter needed for the upper truck hose is 34mm OD since it's ID of that hose.