Burping Cooling System after Vacuum Fill

The Critic

The Critic

Joined
Aug 30, 2004
Messages
31,963
Location
CA
I previously used the Airlift brand vacuum coolant fillers with the universal rubber cone. After refilling with the Airlift, I used a coolant funnel and waited for the thermostat to open. With this method, I would still need to top off the coolant (small amount) after the vehicle cooled down.

I semi-recently switched to the Snap-On coolant refiller than uses the Stant-style adapters; it is a vehicle specific setup. The system vacuums the system much quicker than the universal Airlift tool I used to use. So far, I have used the Snap-On tool on 5 or 6 vehicles and each time, I did not use the coolant funnel after refilling. There has also been almost no change in the coolant level after cool down.

My question: With my new setup, is it consistently safe to vacuum fill the coolant system and release the car without "burping" the cooling system with a coolant funnel?
 
I suspect it is vehicle specific. For example, my OM603.97 in my 350SD is harder to burp, and takes longer to get all the air in, than other vehicles. My 5.9 Cummins burps by itself so easily there’s no follow up.

I dont really know why the start design would pull vacuum faster. Does the universal unit stick further into the radiator neck?
 
Bumping this thread - I tried a new technique that I learned from a technician user group.

Vacuum system and allow system to remain under vacuum for a few minutes. Submerge coolant suction tube in the bucket of coolant, open valve just enough to allow coolant to fill the suction tube. Vacuum system again, usually 5-10 seconds is all that is needed. Perform refill. Top off coolant to the brim of the radiator neck. Install cap, top-off reservoir. Test drive with heat on max hot and lowest fan speed.

Just did a Highlander yesterday using this method. I road tested for 15-20 miles (for an unrelated reason) and parked the car overnight. When I rechecked the level this morning the overflow level had not even moved.
 
You like the snap on that much more than the airlift ? I have been using the airlift for years and years. Kinda chuckle when I see people not using a vacuum method especially on some of these systems
 
MattPersman said:
You like the snap on that much more than the airlift ? I have been using the airlift for years and years. Kinda chuckle when I see people not using a vacuum method especially on some of these systems
Click to expand...
Agreed. Yes, it vacuums down faster and both the air line and coolant suction line are simultaneously connected (so you do not have to swap connections).

It is definitely worth the extra money.
 
If you already have a vacuum pump and a jar, or have $18 to buy a Harbor Freight venturi vacuum pump, $5 for jar of pickles, and a rubber drain stopper for the radiator, the most difficult part of the build is deciding what to do with all of those pickles . . .

The adapter shown is connected to a power steering reservoir. This may similarly be applied to degas a cooling system. If you use a rubber drain stopper in lieu of a radiator pressure test kit adapter, use heavy weight grease to seal the polyethylene hose as it passes through the hole you bore in the rubber stopper to prevent vacuum leaks. Use a hose clamp to prevent the hose from migrating relative to the drain stopper if needed.

jar-n-reservoir.jpg
 
Just wanted to add this:

A40ABFEB-CFB2-4125-ABC7-89419D1AB5FB.jpg

Ford specifies the use of the UView 550000 for refilling coolant on their 3.5L ecoboost engines.

But the instructions still want you to proceed with a bleeding procedure after using the tool.
 
The Critic said:
Just wanted to add this:

View attachment 139710
Ford specifies the use of the UView 550000 for refilling coolant on their 3.5L ecoboost engines.

But the instructions still want you to proceed with a bleeding procedure after using the tool.
Click to expand...
I believe the 3.5 and 2.7 ecoboosts have reverse flow cooling.

Fordtechmakuloco talks about it a bit in this video:

 
Last edited:
I think it depends on the vehicle but I have an Airlift as a DIYer and I never worry about using a funnel or burping after using the Airlift. I vacuum, wait to make sure there are no leaks, then fill, top up as needed and go. Make sure to check the overflow or degas bottle for the correct amount after a little bit.
 
Old thread...new question for you pros.

I recently flushed and filled a 2018 (18-current) JL Wrangler 3.6L without any vacuum assist filler. I have driven it about 40 miles and all seems well. However, I'm concerned about air pockets in the heads, etc.

My question is: Can I use a vacuum tool like the OEM Tools 24444, Mishimoto Purge and Refill, or similar to burp the system, without draining it down and restarting the fill process? Tips? Thanks much.
 
If you are patient a good sealed system will self purge the air out in a few cool/heat cycles. Technically it does not matter what the level in the over flow is as long as the bottom is covered in coolant so as to not suck up air on cool down. When the system is dead cold the radiator should be 100% full.

As the system heats up under pressure, any air in the coolant becomes dissolved in the coolant. As it is pushed into the overflow, which is not under pressure, the air undissolves. I've found replacing the overflow tube with clear tubing shows the coolant in the hose so you know the radiator is full. If there is air in the hose there is air in the coolant and more than likely some sort of minor vacuum leak on cool down.

Best thing they ever did is to go to those pressurized coolant tanks.
 
SHOZ said:
If you are patient a good sealed system will self purge the air out in a few cool/heat cycles. Technically it does not matter what the level in the over flow is as long as the bottom is covered in coolant so as to not suck up air on cool down. When the system is dead cold the radiator should be 100% full.

As the system heats up under pressure, any air in the coolant becomes dissolved in the coolant. As it is pushed into the overflow, which is not under pressure, the air undissolves. I've found replacing the overflow tube with clear tubing shows the coolant in the hose so you know the radiator is full. If there is air in the hose there is air in the coolant and more than likely some sort of minor vacuum leak on cool down.

Best thing they ever did is to go to those pressurized coolant tanks.
Click to expand...
I appreciate the quick reply. In this vehicle, the overflow tube enters the translucent recovery tank near the top and coolant is visible as it enters the tank.

I've driven it and cooled it approximately 4 full heat cycles.
 
I just pour coolant in until the bubbles stop, start the engine and see if I can get more bubbles out, put the cap on and drive it for 5 minutes to get the thermostat to open, and then let it cool down and top it off. You do have to check the overflow every couple days this way but you don't need any special tools


I want a vacuum bleeder
 
roaniecowpony said:
Old thread...new question for you pros.

I recently flushed and filled a 2018 (18-current) JL Wrangler 3.6L without any vacuum assist filler. I have driven it about 40 miles and all seems well. However, I'm concerned about air pockets in the heads, etc.

My question is: Can I use a vacuum tool like the OEM Tools 24444, Mishimoto Purge and Refill, or similar to burp the system, without draining it down and restarting the fill process? Tips? Thanks much.
Click to expand...
My understanding is you need to start from empty/near empty to use vacuum.

I swear my '19 3.6 uses a little coolant and has since Day 1. I don't want to know so I pretend it's not happening
 
You must log in or register to reply here.

Similar threads

E
Coolant Level Dropping in Radiator
2 3
Replies
46
Views
4K
explorer2030
B
Did I destroy my engine?
Replies
17
Views
4K
bluesriderdf
C
Coolant Flush and Change
2 3
Replies
49
Views
4K
Doc8404
U
2016 Volvo V60 Coolant blue or pink - why is mine blue
Replies
14
Views
301
dumkid
P
Vacuum hose for evep system
Replies
10
Views
745
zzyzzx
Back
Top