Easiest method of replacing antifreeze at home?

[jdheff1982]

So, ya, I need to replace the antifreeze as it is only good to +20* F and the temps are coming down close to that. I know that prestone has the cheap flush kit, but does that get the anti out of the block too or is that something I don't need to worry about when adding new anti? Trying to stay cheap with this as I have been quoted near $100 for a complete flush and refill.

Thanks.

[72lb4x4]

An SBC has a plug on each side you remove to drain the block. Often, you need to poke a screwdriver in the hole if it doesn't drain.

[78 Big10 454]

I've used the Prestone kit with great success in flushing the entire cooling system.

[RastaRobb]

That's wha tthe flush kit is for, and works great. Even if you just drained the radiator, and refilled with the lower temp stuff, then rain it, I am sure you would be fine as it mixes with the coolant in the block.

[jdheff1982]

Originally Posted by RastaRobb

That's wha tthe flush kit is for, and works great. Even if you just drained the radiator, and refilled with the lower temp stuff, then rain it, I am sure you would be fine as it mixes with the coolant in the block.

Yeah, that's what I figured. I thought about finding a car wash and draining the rad. there and refilling it so I can avoid making a mess at home.

[919cw313]

^I'm no tree hugger, but that doesn't sound right at all.

[TDS-MN]

Originally Posted by jdheff1982

Yeah, that's what I figured. I thought about finding a car wash and draining the rad. there and refilling it so I can avoid making a mess at home.

Seriously?!?!?!

Antifreeze spill cleanup is so easy, compared to other fluids. If you drain it at home (or anywhere) it WILL come out of the radiator and spill all over your frame rail. But a well-placed bucket can catch the entire contents of the radiator.

Clean-up just requires a little soapy water and a push broom, you won't even know you spilled on the driveway when dried.

I just replaced my radiator, and put a 7"+/- length of nylon hose on the drain of the radiator, which will greatly reduce my mess next time I have to drain it. But I don't think you'd be able to get to where you need to add something like that, when the radiator is still in the truck.

As mentioned, there is still a good amount of coolant in the block, I'm guessing that you'll only get about half of the entire capacity by draining the radiator. The after-market flush kits are good for getting all of the old coolant out, but it does make a bit of a mess.

IMO, $100 seems a little steep for a shop to flush it out, but not TOO far out of line.

Hope you find an option. And I hope it doesn't end up being drained into the car wash floor drain.

[Pyrotechnic]

There's a couple ways to do it and a kit is not really required.

The easiest way and if your city has good water is to just flush the system out with water. Fill, run, drain. Fill, run, drain. After the first couple I've even left the hose in the radiator fill and left the drain plug open while the motor ran. Once you got clear water and your sure all the old is out, drain the radiator then add the amount of antifreeze concentrate your system requires. Top the rest off with water.

You have to know how much your system holds for this method to work right. If you know your system takes 4 gallons of water for example, you would need to dump in 2 gallons of antifreeze concentrate and then top the rest off with water. If your coolant capacity is published in the vehicles manual then you can be reasonably confident that you have a good mix ratio.



The better way to do it is drain the block and heater core after the water flush. Unscrew the drain plugs out of each side of the block after you are done. You will also want to take off the heater core hoses at the radiator and intake and use compressed air to blow the water out. Use liquid automotive thread sealant on the block plugs when you screw them back in, teflon tape sucks and will leak.

This gets the system 99% free coolant and water. Now, go to the grocery store and buy enough distilled water to mix with the amount of concentrate you need. Don't bother with premix, it's a waste of money.

Don't get the orange Dex Cool antifreeze even if it says GM on it. It is poison to any motor not specifically design for it, and it is a piss poor coolant anyway.

Make sure you get the new universal coolant. Is is much like the old green stuff we are used to and it works well.

[tucsonjwt]

I recommend NOT knocking out the drain plugs and reinstalling new ones - too much opportunity for a future leaks in a very old engine. The flush kit works fine - take the waste antifreeze to your local recycling station - look it up for your town on the net if you don't know where it is.
ACE hardware had PEAK antifreeze 50/50 on sale for $1 per gallon after $5 mail in rebate. They usually do this every fall - I have 6 gallons in the shed waiting for my next cooling system leak. I don't know if the deal is still in effect, but you should check it out.
I never use the petcock on the radiator, I just pull off the lower radiator hose and let it drain into a big drain pan - never lose very much that way. I always replace all the hoses when I do this and keep the old hoses stashed in the truck (along with replaced belts) in case of a breakdown on the road. I carry a few extra gallons of water and a few quarts of oil also. Use radiator hose lubricant when you replace the hoses so they don't fuse to the nipples and require cutting when removed.
For economy, I buy oil by the case on sale - same with spark plugs, air filter element oil filters,, PCV breather element, etc. Too illustrate how little I drive, I am down to my last case of $1 per quart Penzoil.
A lot of coolant is left in the block when you drain the radiator, but you really don't need to flush it. I personally prefer to just drain what I can through the radiator and heater core and replace the coolant with antifreeze and distilled water.

[csb#356]

If you only drain the radiator and then flush and drain, How much old coolant and mineral deposits and rust are left in the block? Drain the block and the radiator and flush with non-sudsing laundry detergent and water. Take out the thermostat and fill with the mixture of soap and water and then run the engine for a couple minutes. repeat this until what you are draining out is totally clear. When you are happy with whats coming out then flush it out with straight water a couple times until you get rid of all the soap residue. then fill with a 50/50 mix of distilled water and antifreeze.

[78 Big10 454]

What I wouldn't give to pay a buck a quart for oil!

[motornut]

I've used a flush kit lots no probs
And also dumped lower into buckets
And used the garden hose repair, with the connection like an air line on the core hose,
use extra rad hoses from pump to the bucket,
But have seen those block drains snap off, flush
A lot of garages will take the old antifreeze around here
Posted via Mobile Device

[flamingbig10]

It not the best way to do it but if your coolant isn't to nasty drain the radiator and water pump and add strait anti freeze

[raceman6135]

Originally Posted by flamingbig10

It not the best way to do it but if your coolant isn't to nasty drain the radiator and water pump and add strait anti freeze

If this method is used, you HAVE TO check the strength of the antifreeze/water mix with the proper hydrometer. Why? Because if you have too much antifreeze in the mix, it is just as bad as not having enough. This is because pure antifreeze will freeze!

Most antifreeze manufacturers recommend no more than 70% antifreeze/30% water, and in fact, a 50/50 mix is usually best. That will give you freeze protection down to -34F with most brands of antifreeze, which is a pretty safe mix.

[donut]

Like raceman6135 said, more is not better. That being said, I like the Prestone flush kits, esp. if it's an unknown cooling system or you know it's nasty.
flamingbig10 said add straight AF. In my truck, once drained, I went with a gallon of straight (it will mix with whatever water is left over in the system) then check the strength (once mixed) and top with whatever is needed. Get yourself a little tester, they're like a couple of bucks and worth it vs. a froze up truck. IIRC they're s a recent thread about someone starting an engine "break in" on straight water, and the block froze overnight, not pretty.

I usually look for the AF on sale, buy a couple gallons, what doesn't get used right away gets mixed 50-50 and used to "top off". Recycle the old stuff, I don't want it in my well.

[BigBlocksRule]

Freezing antifreeze is a problem that I'm glad is limited to you folks in the north. I know it will freeze at a higher temp than the correct mix, so you folks who experience temperatures lower than -20F don't have a choice.
I've run straight green in every engine I've built for several years. Never had any problems with it, and it's always clear and clean, the anti-corrosion properties are great!
As far as getting rid of the old stuff, either use a small hose on the outlet fitting or a small funnel and hose to direct it into your bucket.
Don't worry if you spill a bit, cats love the stuff and will clean it up for you.

[motornut]

when driving the air going threw the rad cools the coolant (even more when below 0C)
for heat you do need water in the mix
i see -40C and seen colder too
havn't had anti freeze freeze,but have seen it go slushy
then it won't flow threw the fins,and that freezing air will make it even worse
then it would blow out

distilled water for sure btw,to much crud in our drinking water lol

[donut]

BigBlocksRule- the "slushing" antifreeze can be a problem, it can also point out weak points in the cooling system, when it starts to freeze up, it expands. Flip side of the coin, living in the Phoenix area when I was younger, I noticed my cooling system was more efficient shedding heat with a 50/50 mix. FWIW, I noticed straight water was more efficient than straight AF, but didn't have the anti corrosive properties.

My location may say SC, but I'm a fairly recent transplant. Lived in Maine and AZ for a good many years, and have dealt with both extremes.

[75gmck25]

One technique I've tried at home is to first drain the radiator completely. Then refill it with water and warm it up completely. Then let it cool enough so you can drain it. If you do this about 3 times you get to a point where you have mostly water (you can always check it with an antifreeze SG checker). The multiple drain and fill should also get most of the gunk out of the system.

Then drain it a final time. Look up how much your cooling system holds and add half that amount of straight antifreeze to the radiator. Warm it up again until the thermostat opens, and keep adding antifreeze until you have the total 50% amount of antifreeze in the system. Put a 50% mix in the overflow, put the cap back on and let it pressurize completely. After it cools, recheck the radiator and overflow and add 50% mix as needed.

Bruce