How to drive air out from radiator?
Thread Starter
Newbie
Joined: Nov 2014
Posts: 12
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2011 ML350 4MATIC
How to drive air out from radiator?
My coolant tank was broken in an accident, then I bought a new one and installed it successfully. Of cause, I refilled the coolant MB325, and it took about 1.7 gal.
Today I found that the temp seems a little high. It is 31F, but the coolant temp is high to 90~100 ℃. And when I stop and open the hood to touch the coolant system, all are how but the radiator is as cold as the body.
But the warm wind is OK.
So I think there must some air in the radiator. It stops the coolant enter the radiator.
Then, how to drive air out from the radiator?
Thank you.
Today I found that the temp seems a little high. It is 31F, but the coolant temp is high to 90~100 ℃. And when I stop and open the hood to touch the coolant system, all are how but the radiator is as cold as the body.
But the warm wind is OK.
So I think there must some air in the radiator. It stops the coolant enter the radiator.
Then, how to drive air out from the radiator?
Thank you.
Thread Starter
Newbie
Joined: Nov 2014
Posts: 12
Likes: 0
2011 ML350 4MATIC
Thread Starter
Newbie
Joined: Nov 2014
Posts: 12
Likes: 0
2011 ML350 4MATIC
Thread Starter
Newbie
Joined: Nov 2014
Posts: 12
Likes: 0
2011 ML350 4MATIC
Senior Member
Joined: Aug 2009
Posts: 427
Likes: 57
13 GL350, 14 SL550
I think more is going on here than you're aware of...
What was damaged in the accident.. the white plastic coolant *reservoir* bottle?
If you replaced this and refilled, it holds nowhere near 1.7gal of coolant/water.
The entire radiator and coolant reservoir combined hold approximately that much. So that tells me that you replaced the reservoir, but filled the entire radiator too.
Questions:
1. Are you sure the radiator didn't have a leak also? Was it completely undamaged?
2. Did you check the hoses also, and/or do a pressure test on the system to make sure it's undamaged?
3. Were you adding just coolant or 50/50(coolant/water)? Because if you added 1.7gal of coolant alone, you don't have enough water in the system.. your entire system is now full of mostly just coolant and no water.
What was damaged in the accident.. the white plastic coolant *reservoir* bottle?
If you replaced this and refilled, it holds nowhere near 1.7gal of coolant/water.
The entire radiator and coolant reservoir combined hold approximately that much. So that tells me that you replaced the reservoir, but filled the entire radiator too.
Questions:
1. Are you sure the radiator didn't have a leak also? Was it completely undamaged?
2. Did you check the hoses also, and/or do a pressure test on the system to make sure it's undamaged?
3. Were you adding just coolant or 50/50(coolant/water)? Because if you added 1.7gal of coolant alone, you don't have enough water in the system.. your entire system is now full of mostly just coolant and no water.
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Senior Member
Joined: Aug 2009
Posts: 427
Likes: 57
13 GL350, 14 SL550
There is no 'radiator' cap on these vehicles. The only cap is on the reservoir.
As long as the reservoir is filled to the 'full cold' level when cold, things are properly topped up.
If you suspect you have air, remove the reservoir cap when cold, then start the truck and warm it up. You need to have all of the heat vents blowing hot inside the truck (heat on high) to know that the thermostat has opened properly. Rev the engine a few times also.
Then put the cap back on and you're done.
If that doesn't fix it, the problem lies elsewhere.
As long as the reservoir is filled to the 'full cold' level when cold, things are properly topped up.
If you suspect you have air, remove the reservoir cap when cold, then start the truck and warm it up. You need to have all of the heat vents blowing hot inside the truck (heat on high) to know that the thermostat has opened properly. Rev the engine a few times also.
Then put the cap back on and you're done.
If that doesn't fix it, the problem lies elsewhere.
Thread Starter
Newbie
Joined: Nov 2014
Posts: 12
Likes: 0
2011 ML350 4MATIC
I think more is going on here than you're aware of...
What was damaged in the accident.. the white plastic coolant *reservoir* bottle?
If you replaced this and refilled, it holds nowhere near 1.7gal of coolant/water.
The entire radiator and coolant reservoir combined hold approximately that much. So that tells me that you replaced the reservoir, but filled the entire radiator too.
Questions:
1. Are you sure the radiator didn't have a leak also? Was it completely undamaged?
2. Did you check the hoses also, and/or do a pressure test on the system to make sure it's undamaged?
3. Were you adding just coolant or 50/50(coolant/water)? Because if you added 1.7gal of coolant alone, you don't have enough water in the system.. your entire system is now full of mostly just coolant and no water.
What was damaged in the accident.. the white plastic coolant *reservoir* bottle?
If you replaced this and refilled, it holds nowhere near 1.7gal of coolant/water.
The entire radiator and coolant reservoir combined hold approximately that much. So that tells me that you replaced the reservoir, but filled the entire radiator too.
Questions:
1. Are you sure the radiator didn't have a leak also? Was it completely undamaged?
2. Did you check the hoses also, and/or do a pressure test on the system to make sure it's undamaged?
3. Were you adding just coolant or 50/50(coolant/water)? Because if you added 1.7gal of coolant alone, you don't have enough water in the system.. your entire system is now full of mostly just coolant and no water.
Checked by myself and two body shops, we all confirm that the cooling system is alright except the expansion tank. Radiator, hoses, are all OK.
According to the owner's manual, all the coolant system need 9.5 L coolant, about 2.5 gal. Also, after the accident happened, I drove it about 10 miles until I found the expansion tank is damaged. So I think coolant should run out to empty during this travel.
The owner's manual says that the only coolant option for this ML350 is MB325.0 that I fill 1.7 gal into the tank. Should I mix it with water?
Thread Starter
Newbie
Joined: Nov 2014
Posts: 12
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2011 ML350 4MATIC
I just drive back.
The coolant temp reaches about 90 ℃, in 6 miles and about 10 minutes from a complete cool down. Maybe it is normal?
But after I just stop the car in front of my house and left the engine on, I opened the hood, touched the radiator again, it's cold. But the hoses are warm.
Then I opened the cap, some coolant ran out. At least it proves that there is no leak.
The thin hose connected with the top of the tank seems return the steam back to the tank.
Can I try to pull it out to remove the air.
The coolant temp reaches about 90 ℃, in 6 miles and about 10 minutes from a complete cool down. Maybe it is normal?
But after I just stop the car in front of my house and left the engine on, I opened the hood, touched the radiator again, it's cold. But the hoses are warm.
Then I opened the cap, some coolant ran out. At least it proves that there is no leak.
The thin hose connected with the top of the tank seems return the steam back to the tank.
Can I try to pull it out to remove the air.
Senior Member
Joined: Aug 2009
Posts: 427
Likes: 57
13 GL350, 14 SL550
I think you're touching AC parts not the radiator. If coolant temp is 90C the radiator should be that temperature also. But because of the cooling vanes it may feel cooler. Still should feel a bit hot, not room temperature.
I wouldn't worry about it though. Based on what you're now telling us, things sounds normal.
90C engine temp, no leaks, system holds pressure, hoses are hot... these are all good signs.
Just watch that the temp doesn't go to 100C or higher (unless it's a really hot day, your idling in traffic with AC running, etc.) and you're fine.
I wouldn't worry about it though. Based on what you're now telling us, things sounds normal.
90C engine temp, no leaks, system holds pressure, hoses are hot... these are all good signs.
Just watch that the temp doesn't go to 100C or higher (unless it's a really hot day, your idling in traffic with AC running, etc.) and you're fine.
Member
Joined: Dec 2013
Posts: 219
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From: Bluffdale
2017 AMG C 43 (W205); 2019 E 300 (W213); 2008 ML 320 CDI (W164)
In general if you have air pockets in the cooling system after a system drain and refill, the air pockets should disappear after a few (3 to 6) hot-cold cycles. When the engine heats up the air pockets fill up with steam and when the engine cools down the pockets of steam contract considerably and suck coolant fluid into the space where these pockets occur.
Be careful not to allow the engine to get above normal operating temperature during the first few cycles after a refill when the amount of coolant in the system is still less than it should be. Top up the cooling system every time before the start of the next warm-up cycle. Continue to do this until the coolant level doesn't drop anymore after a few hot-cold cycles.
Be careful not to allow the engine to get above normal operating temperature during the first few cycles after a refill when the amount of coolant in the system is still less than it should be. Top up the cooling system every time before the start of the next warm-up cycle. Continue to do this until the coolant level doesn't drop anymore after a few hot-cold cycles.
