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Draining Coolant from radiator

Big T

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Is there a way to safely drain the coolant from the radiator so it can be reused? I just replaced the coolant and radiator, but continue to have a leak from the lower hose at the radiator. I bought a new hose and intend to replace use a screw tighten hose clamp as opposed to the squeeze to open clamp. Pretty certain the lower hose is original and has 231K miles on it. It’s not a deal killer, but I’d like to save a reuse the coolant. Is there a way to attach a hose to the drain valve on the radiator?
 
It depends on the drain cock. Some of the nice ones are equipped with a sort of a tube that a hose can be slipped over.
The original equipment radiator in My truck did not have that option. It was a funky plastic like a 1/2 turn unit that was flat on the face. It let prestone sort of spew out wherever it wanted to splash out at.
Get one of those big square funnel affairs that sets atop of a drain pan. That will catch the most of the spillage.
Clean the channel area below the radiator before starting.
If mud or debris gets into the coolant, when pouring it from the drain pan back to a container, have a old T-Shurt laid inside of the funnel. Three or four clothes pins can help to hold the shirt material from sagging into the funnel and making it clog easily.
 
It depends on the drain cock. Some of the nice ones are equipped with a sort of a tube that a hose can be slipped over.
The original equipment radiator in My truck did not have that option. It was a funky plastic like a 1/2 turn unit that was flat on the face. It let prestone sort of spew out wherever it wanted to splash out at.
Get one of those big square funnel affairs that sets atop of a drain pan. That will catch the most of the spillage.
Clean the channel area below the radiator before starting.
If mud or debris gets into the coolant, when pouring it from the drain pan back to a container, have a old T-Shurt laid inside of the funnel. Three or four clothes pins can help to hold the shirt material from sagging into the funnel and making it clog easily.

Yeah I'm thinking a funnel with hose into a bucket collecting from the radiator drain cock.
 
If the drain cock is of the pipe thread type and it does not have the hose nipple on it, after You get it drained, remove that drain cock and go to tje parts store and get one that has the hose nipple attached.
You will thank Yourself later on in life that You did that.
 
If the drain cock is of the pipe thread type and it does not have the hose nipple on it, after You get it drained, remove that drain cock and go to tje parts store and get one that has the hose nipple attached.
You will thank Yourself later on in life that You did that.

Drain cock has a metal "T" that you turn to open. Presumably pulls out an opening which then lets coolant dribble out all over. There is a metal tray with lip under the drain cock and the radiator for that matter. That disperse coolant EVERYWHERE. I will need to hold a funnel with hose attached, directly under the drain cock and drain it into a bucket.
 
Gm is not your friend on this.
Yeah AK did extra work drilling the hole, but it depends how bad you hate cleaning the mess.

A rotor broach drillbit is ideal because you won’t drill through and hit the parts you want to keep like the petcock. iirc harbor freight sold a cheap set. Then slide a hose on it.

Yes this is a pain, GM didn’t care how annoying this is for diy mechanics. There used to be a funky ‘tool’ for this that was basically a custom 90° fitting with a drain hose on it. It was annoying but worked and cost around $250 back jn the 90’s. 99% of pro mechanics just put a 30” square catch pan under it and don’t re use the coolant. This is why I was saying start with a good pressure washing job so you can use a big catch can and reuse the coolant. If you have dirt, oil, etc on the metal in the area and get it back in the system it will ruin water pump seal and replacing the water pump is needed within a couple months.
 
I think a piece of tin, about six or eight inches long, bent into a V and held under the drain cock might work okay too.
I take those squarish shaped lacquer thinner-mineral spirits tin cans and use a utility knife like a can opener and cut one side out of the can.
Bend the sharp edges into tje can and You then have a real nice storage container.
Take the flat piece of tin and bend that into the V for the drain.
 
Yeah, GM didn't play nice for us to drain the coolant. when I did mine I ended up pulling the smaller hose on the lower rad hose Tee. and fed it into a 5 gallon bucket. since your replacing that hose you might try there or even cut into the lower rad hose having the bucket under there. at least you'll be able to save the majority of the coolant.

I like the concept the semi trucks have here at work where there's a drain on the lower rad hose out in the open. I had thoughts of finding a small section of pipe and splicing into the lower hose for a drain like those trucks are.
 
Yeah, GM didn't play nice for us to drain the coolant. when I did mine I ended up pulling the smaller hose on the lower rad hose Tee. and fed it into a 5 gallon bucket. since your replacing that hose you might try there or even cut into the lower rad hose having the bucket under there. at least you'll be able to save the majority of the coolant.

I like the concection of pipe and splicing into the lower hose for a drain like those trucks are.

I've considered using that smaller hose that goes into the "T" of the lower hose. Isn't that smaller hose for the overflow reservoir? If so then I'd get coolant from the reservoir coming out the small hose and the rest coming out the "T" of the lower radiator hose. I tried but could not remove that smaller hose from the "T". It would need to be cut and I would have to replace which I'll be doing anyway.]

This is giving me ideas.

Wife is doing well enough that she's taking off to geocache with friends in Salt Lake City this weekend, leaving me home in Montana. I should at least do this leak fix project and install the new fuel injectors this weekend. The valve cover oil leak and turbo exhaust side leak represent risks that could have the truck down a couple days and can wait for when my wife is here with her 4Runner. Alternatively, I could just defer and go fishing.
 
Fishing sounds like a plan! any neighborhood kids around who want to learn some wrenching? you could host a fishing day in return for them doing the work while you sit back and supervise lol

Just one extended family with kids all in one home. They are real young, like 3 and 4. I think daughter and her kids moved in with parents.
 
@Big T another idea... since your replacing that hose at the Tee, pull the inner fender and unclamp that hose at the coolant bottle and pull it down into a bucket. you'll loose whats in the bottle but catch most everything in the radiator without making too much of a mess. then you can drain the rest from the radiator with the drain by jacking up on the drivers side and that will allow the runoff to go to the drivers side into another pan.

just a thought
 
@Big T another idea... since your replacing that hose at the Tee, pull the inner fender and unclamp that hose at the coolant bottle and pull it down into a bucket. you'll loose whats in the bottle but catch most everything in the radiator without making too much of a mess. then you can drain the rest from the radiator with the drain by jacking up on the drivers side and that will allow the runoff to go to the drivers side into another pan.

just a thought

Alternatively, I will do as described and hastily thrown on the new hose at the coolant bottle, directing both that and the removed hose into a bucket to get it all.
 
yes, that hose has a bell on the end where it connects to the coolant bottle, at least mine did on my 95. I couldn't find a replacement hose around me so I ended up getting some 1 inch silicone and 5/8 inch silicone hose and a 5/8 barbed union. the 5/8 will fit inside the 1 inch with just fine and the barbed union slid inside the 5/8 hose to make it ridged then clamped it all together as one hose. it was all I could do besides having to order an OE hose and wait 3 extra days! it wasn't the best thing to do but it worked and haven't had any issues yet. when I did my water pump later, I actually tried to seperate the two so I could do the drain and save the coolant. needless to say I could not get the two apart!

for yours, if ordering the lower rad hose, the complete hose should come with that hose already attached as a complete assembly.
 
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