Idea to AVOID BUBBLES on a Radiator Drain & Fill

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Hey, I just sorta had an epiphany....
I have one of those Carlisle "No Spill" funnels and I was thinking, as I was worrying about getting air bubbles out during a radiator drain and fill, that if I put that on the radiator and filled it and then drained from below then there would be a continuous flow of new coolant migrating down behind the old coolant leaving via the petcock with ZERO bubbles as long as I kept it fill on the no spill funnel.

NO SPILL FUNNEL LINK


Any "cons" to this? To heavy on the radiator neck?
 
Don't do your coolant drain-n-flush if you are not mechanically competent to begin with.

some cars (engines) are particularly sensitive to the existence of air bubbles to begin with (causing heater core blockages, some may even lead to HG leaks due to partially overheating of the cyl head (if serious enough).

When in doubt, don't do it. Pay an experienced mech to do it instead.

Also: most automobiles sold during the last 15+yrs are on long-life coolant (where factory fill lasts 10yrs before needing their first coolant change, esp. P-OAT type in various Japanese cars). Why are you doing yours? Is yours due now?

Q.
 
Yep, today is not like the good old days when you could prop open the thermostat with a couple of aspirin. They would hold it open so you could fill the cooling system and get most if not all of the air out.

Today, not so much.
 
I was just thinking about the future with my corolla. Now that I think, I realize that the corolla is an open system so it would purge bubbles to the overflow tak.... I would think.


But his idea of keeping a complete unbroken replacement stream of coolant from the large funnel at the top of the rad is increasingly interesting.
 
Along those lines, maybe you could pull out the overflow reservoir hose, then stick that into a fresh bottle of coolant, then open the drain. I don't know if gravity is enough to open the valve to suck in the fresh coolant though. Maybe you could use some sort of vacuum on a hose connected to the drain to suck it out.

I'd personally not bother, just drain, fill, burp it. I do it all on ramps to try keep the radiator as high as possible, probably doesn't make a difference.
 
I'm cynical about the coolant taking a complete trip through all corners of the engine.
 
You can pull a vacuum on the coolant.

On the newer cars the heater core is now an active loop. It is the main path, or at lest shared path, for all the coolant flowing through the block.

There usually is some sort of highest hose such as a radiator bypass. You can pop this open when filling and vent the system from there.
 
I know Eric the car guy on youtube swears by those things. I have never used them as my Equinox has an air bleeder valve and my Malibu I run a little over the full mark and top off the next few days until it is level.
 
Originally Posted By: stang5
http://www.amazon.com/gp/product/B0002SR...d=ATVPDKIKX0DER

This is what I used in all the cars I serviced and it works great.


Yup, I have and use this tool on every car that comes in for a coolant service. Ever since using this tool, it has shaved at least 20 min off each coolant service since it speeds up the refill and eliminated the need to do multiple warm-up cycles to confirm proper thermostat operation.

It is definitely a must have tool. In fact I wouldn't do a cooling system service without it.
 
On the Ford Taurus they had the cap on the reservoir. It was pressurized and in the loop. They called it a degassifier and it worked great.
 
Use the no-spill funnel to fill the system with, and start the vehicle with it still attached. This is assuming it fits your radiator or coolant bottle. Leave that hooked up so that as it heats it can expand without spilling over, and when the t-stat opens, it'll have a large volume in the funnel to suck back in and you can immediately top it off.
 
Engines that have the t-stat on the lower hose also are much easier to fill without trapping much air as you don't have to wait for the engine to heat up.
 
I did the mistake once when replacing the water pump on my Dodge Ram 4.7
to just refill the coolant from the radiator cap as I always did on other vehicles.

Got as much coolant in there as I could (about 1-2 quarts less of full system capacity)
and be squeezing the upper hose a bit to burp out some air from the top of the radiator.
(t-stat housing is on the lower hose of the 4.7).

After letting the engine idle for a while to do a final burp of the system, radiator cap off the level barely dropped but
the engine temperature gradually got way above the normal operating range up to 'HOT' on the gauge as if the thermostat never openned.

Closer inspection and I found that no matter how much coolant I had put in the radiator,
the water pump / engine block / heads had a major air pocket inside and wasn't circulating fluid.
Removing the upper hose from the radiator and pouring in coolant to fill the pump and upper engine passages was the only to get it functional.

I hate to imagine how high the cylinder head temps got during this mistake.
 
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I didn't use any tool except the standard funnel to fill the coolant/water into my S2000 in the last change I did few month ago(I flushed the system with distilled water once).

I parked the car on inclined driveway facing to the street so the front end is lower to drain as much coolant from the system as possible with only the radiator drain plug loosen. When I refilled the system with Peak Global Lifetime concentrate I park the car facing the garage so the front is the highest point, I poured in a full gallon(system capacity is 9.6 quarts including reservoir) then added distilled water to full.

Next few days I top off the reservoir with distilled water several times, after 2-3 top off(about 10-12 oz total) the car didn't have any sign of air in the system.
 
Originally Posted By: HTSS_TR
I didn't use any tool except the standard funnel to fill the coolant/water into my S2000 in the last change I did few month ago(I flushed the system with distilled water once).

I parked the car on inclined driveway facing to the street so the front end is lower to drain as much coolant from the system as possible with only the radiator drain plug loosen. When I refilled the system with Peak Global Lifetime concentrate I park the car facing the garage so the front is the highest point, I poured in a full gallon(system capacity is 9.6 quarts including reservoir) then added distilled water to full.

Next few days I top off the reservoir with distilled water several times, after 2-3 top off(about 10-12 oz total) the car didn't have any sign of air in the system.


I have done this before and it works well...
 
I drill a 1/16 inch hole in a new thermostat prior to installing it. The new ones for my Chrysler doesn't seem to have these. Usually air is an issue if the thermostat is at the highest point in the cooling system otherwise it will be belched out to the recovery bottle.
 
Originally Posted By: stang5
http://www.amazon.com/gp/product/B0002SR...d=ATVPDKIKX0DER

This is what I used in all the cars I serviced and it works great.

I have one I use on my parent's Prius and on a Nissan we owned as well as a neighbor's Frontier - it works quite well once you get the hang of it.

The Lisle Spill-Free funnel works great for most cars - a Honda tech showed me it and except on a Toyota Sienna and a Lexus LS400, I use it almost every time I do coolant/radiator work. The Sienna's fill point is part obscured by the cowl, the Lexus burps itself.
 
I also drilled two small holes in my thermostat. Something like 1/16" or 1/8". I used to top off with radiator/coolant and have air pockets before the drill action. Temp would go sky high but rad was full. Cured that issue.

Also another plug for raising the radiator high as possible. Lucky for me I have a steep driveway. Let it idle with the radiator up nice and high for a bit. I didn't need to do this but did it anyway.

The two holes in the thermostat burped mine while adding coolant in my level garage.

Those tall funnel burp style deals are a waste of time if your thermostat will not pass any coolant. Those get the coolant level in the radiator only, higher but again does no good to burp the engine block.

slomo
 
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