If the OP lives in the northern areas where the temps get into the below zero range, then I would not use premix coolent. The OP stated that he thonks that 2.6 quarts of water remail after a flush.
That would bring the freezing point of his coolent to just about Zero or a bit higher.
So he had better hope it’s not a bitter winter.
I also fill with the cap off and the engine running and have lost little coolent thru the years.
Yosemite
Yeah, I’m in Detroit, it get’s a little nipply.
Same here West of Milwaukee.
Yosemite
@keith
There are two drain plugs on both sides of the oil pan, but the knock sensors are plugged into them. They look well rusted and grimed up.
Yosemite, I didn’t say to use premix, at least not after the OP mentioned that he had flushed the block with fresh water. I did say to premix some distilled water into the antifreeze. 2 qts of water in 7 qts of antifreeze isn’t going to be overly diluted by the remaining water.
I’d rather have a little over 50/50 for those cold wind chill days amd nights.
Me too, and the extra antifreeze provides more corrosion protection. In fact, if were my system, I’d use 8 qts of antifreeze, but in this situation, I would premix in one qt of water to the 8 qts of antifreeze for the initial filling.
Demo, I stand corrected on the location of the drain plugs and I still support your decision to leave that sleeping dog alone.
More and more thermostats have weep holes in their base and I always recommend drilling the hole in thermostats that lack it. Without that weep hole the coolant in an engine will expand as it heats and flood out the radiator before the thermostat opens if the cap is off. For the inexperienced DIYer that situation can result in getting scalded in the confusion. In an effort to avoid a problem I gave advice based on assuming that the thermostat had no weep hole.
But I was just a mechanic. Never quite qualified as a Technician.
In my 3800s, I believe I always added 2 1/2 gallons of un-mixed. What it amounted to was filling the radiator as much as possible with un-mixed and never could seem to get any more in. It was fine in Minnesota. So guess that’s what I’d do. There is water in the block and the heater core so I’d rather have a little stronger mix.
“But I was just a mechanic. Never quite qualified as a Technician.”
When I was working for the US army, I was a mechanic
Then when I was at the dealer, I was a technician
Now that I’m a fleet civil service mechanic, I’m once again a mechanic
Things have come full circle
LOL
When I do a coolant flush on my 89 Mustang GT, I always fill the radiator to the top after draining… When I start the engine the water pump turns and the coolant drops some. I keep adding coolant until radiator stays full… Put the cap on and run it for 10 more minutes. Let engine cool for about 20 - 30 minutes then check the level and top off as necessary. All done. I am not saying “anyone is wrong here” as I have been doing it this way for 50 years and it worked every time even on other newer cars.
@Tester … I’m in your camp here. I always refill an engine block…new or old by running the engine with the cap off while parked uphill on an inclined driveway. That gets the most air out of the system quickly. I’m experienced with this technique so I have no problem. If you are a novice…leave the cap on and use the bleeder screw. BTW…the direction of coolant flow is meaningless. The service manuals also tell you to drain the radiator with the petcock but I prefer the lower radiator hose removal method. It works better and I don’t generally have a week to drain a radiator.
I never use premix, if I flush my system with water and drain, I don’t know how much water is left in the system so I put 1/2 the system capacity of full strength in the coolant tank halfway to the cold level, the rest goes in the rad and then fill both with water. I then mix up some 50/50 in a jug to top off when cold. I then know that I have at least 50/50 in there which is all I care about
I remember years back that I had one that had that much rust.
I was young and foolish at that age.
I pulled the thermostat out and drained the system and flushed it like he did. Then I drained enough water out and as it was running (cold engine) I added about a quart of muriatic acid.
You could tell it was working because…even with a cold engine…the water gushed out from the open cap 6 inches high. I just kept adding water little by little. When I thought that it was in the system long enough I shut off the engine, pulled the top hose and stuck a piece of pipe on the hose to divert the liquid far enough away. Then I started up the engine and kept the system full thru the removed cap.
I had to rinse the whole engine compartment real good because when that baby erupted, the fan threw the water/acid everywhere.
Now I’ll just spend the money on a new radiator.
I’ve flushed a few heater cores with a little drill opperated pump and Lime Away, but that’s just on those models that you’d have to spend hundreds having the AC evacuated and recharged, just to change out a heater core.
Yosemite
Was that a ’ professional technician’ in the video? Surely not.
Howie, your Mustang engine dates back to the 60’s so you do it old school.
Bing, seriously? Have you ever seen the freeze level protection chart for ethylene glycol out to 100%, there is a reason it stops at 67% (or 70% on some) on the charts on the containers. You can take propolyene glycol out to 100% as its freeze points keeps getting lower with an decrease in water.
That video, that guy will not work on my car. Trigger nozzle in the radiator?
Holy petcock @keith Do you think I’d be stupid enough to put in 100% antifreeze? I said I didn’t remember the capacity since it has been years since I’ve done a drain and refill. I looked it up though and capacity was 13 quarts so I must have put in 1 1/2 to 1 3/4 gallons and the rest mixed into the overflow. That at the worst would be 50-60%. No need to lecture on the properties of glycol. I’ve been reading the charts and labels for near 50 years.
From Keith Howie, your Mustang engine dates back to the 60’s so you do it old school
You are correct Keith…, I own older cars, 74 Nova a 59 T-Bird. plus the 89 Mustang GT…All go to classic car shows… I have always done it that way as that’s how my dad used to do it. ( May he RIP ) I never go over a 50/50 mix as pure or higher levels of anti-freeze have less heat transfer from the engine block. Unless your temps are going to drop below -34 F 50/50 is your best concentration. No one here in FL would ever run a 70/30 mix.