GL 420 cdi - Pressure in cooling system
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W203 C320 cdi
GL 420 cdi - Pressure in cooling system
Hi all.
My cousin has a GL 420 cdi that has high pressure in the cooling system. We went to the dealership, they did CO2 test to see if there is any CO2 in the water. They didn't find any. They finally said it might be a head gasket problem. My cousin changed the right head gasket. But unfortunately he still has the problem. He is about to change the left one. Is there anyone here that had a similar problem or that could point us to potential sources for this problem ?
More info:
When we turn on the car, the pressure stays normal. No particular problem. Even after letting the engine run for 5 minutes. When we use the car for a while, the hoses start to be very hard and if we open the water tank's cap, the pressure make water spill out of the tank.
Please tell us your taughts. We are trying to save his holidays with his kids.
Thanks a lot
My cousin has a GL 420 cdi that has high pressure in the cooling system. We went to the dealership, they did CO2 test to see if there is any CO2 in the water. They didn't find any. They finally said it might be a head gasket problem. My cousin changed the right head gasket. But unfortunately he still has the problem. He is about to change the left one. Is there anyone here that had a similar problem or that could point us to potential sources for this problem ?
More info:
When we turn on the car, the pressure stays normal. No particular problem. Even after letting the engine run for 5 minutes. When we use the car for a while, the hoses start to be very hard and if we open the water tank's cap, the pressure make water spill out of the tank.
Please tell us your taughts. We are trying to save his holidays with his kids.
Thanks a lot
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Joined: Jun 2019
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W203 C320 cdi
It is unusual pressure. The hoses are rock hard after 5 minutes driving.
Anyone here have an idea of what could cause the problem ? It is the same symptom as a head gasket problem, but no CO2 in the water, no smoke, no water in oil.
Anyone here have an idea of what could cause the problem ? It is the same symptom as a head gasket problem, but no CO2 in the water, no smoke, no water in oil.
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W203 C320 cdi
He is not loosing coolant and we changed the thermostat. And when the car was at the Mercedes dealership, the guy tried to put an other cap, but the problem was still there.
He changed one of the two head gaskets so far, without success. The second is going to be changed this week. And if the problem is still there, I really don't know what we could try next.
The Mercedes dealership is not really helping.
He changed one of the two head gaskets so far, without success. The second is going to be changed this week. And if the problem is still there, I really don't know what we could try next.
The Mercedes dealership is not really helping.
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He is not loosing coolant and we changed the thermostat. And when the car was at the Mercedes dealership, the guy tried to put an other cap, but the problem was still there.
He changed one of the two head gaskets so far, without success. The second is going to be changed this week. And if the problem is still there, I really don't know what we could try next.
The Mercedes dealership is not really helping.
He changed one of the two head gaskets so far, without success. The second is going to be changed this week. And if the problem is still there, I really don't know what we could try next.
The Mercedes dealership is not really helping.
it is possible you have a clogged radiator or a pinched hose somewhere. diesels run very cool by default (when not pushed hard) so a clogged radiator would not result in higher engine or coolant temps, but a higher pressure is common on the supply side. check the hardness of the radiator on the exit side - if it is soft than you have a clogged radiator. if it is hard like the intake side - check the system for hose kinks
Last edited by alx; Jun 17, 2019 at 12:51 PM.
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W203 C320 cdi
Unfortunately it is also hard after the radiator, yes. So the investigation continues 😣
Someone told me that a clogged particle filter could result in having to much heat in the cooling system and having the water boiling and getting under pressure. I don't really know how this is possible. Have you guys ever heard of this ?
Someone told me that a clogged particle filter could result in having to much heat in the cooling system and having the water boiling and getting under pressure. I don't really know how this is possible. Have you guys ever heard of this ?
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Unfortunately it is also hard after the radiator, yes. So the investigation continues 😣
Someone told me that a clogged particle filter could result in having to much heat in the cooling system and having the water boiling and getting under pressure. I don't really know how this is possible. Have you guys ever heard of this ?
Someone told me that a clogged particle filter could result in having to much heat in the cooling system and having the water boiling and getting under pressure. I don't really know how this is possible. Have you guys ever heard of this ?
so, no...what you might have is a collapsed hose on the return side. it might or might not be visible. if all hoses are correct i would look at the water pump. is it the stock one with the stock pulley?
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E55, GLS450, GL63, GLE350
If you live in a very hot area, someone may have installed a smaller water pump pulley that spins the pump faster to move coolant through the system faster in hopes of the engine running cooler. One of the side effects could be an over pressurized system.
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W203 C320 cdi
True.
I guess the pressure made it difficult to spot, but I couldn't see noticeable difference in water level.
Thanks a lot for your help !
I think the Mercedes dealership where I went is a scammer. A friend warned me about him but I didn't listen. There should have been exhaust gas residue in my water. I should have bought a tester kit and tested it myself.
I guess the pressure made it difficult to spot, but I couldn't see noticeable difference in water level.
Thanks a lot for your help !
I think the Mercedes dealership where I went is a scammer. A friend warned me about him but I didn't listen. There should have been exhaust gas residue in my water. I should have bought a tester kit and tested it myself.
Last edited by Said Ridan; Jun 26, 2019 at 01:18 PM.
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E420 CDI
True.
I guess the pressure made it difficult to spot, but I couldn't see noticeable difference in water level.
Thanks a lot for your help !
I think the Mercedes dealership where I went is a scammer. A friend warned me about him but I didn't listen. There should have been exhaust gas residue in my water. I should have bought a tester kit and tested it myself.
I guess the pressure made it difficult to spot, but I couldn't see noticeable difference in water level.
Thanks a lot for your help !
I think the Mercedes dealership where I went is a scammer. A friend warned me about him but I didn't listen. There should have been exhaust gas residue in my water. I should have bought a tester kit and tested it myself.
Question, you resurface the head? The block? Because its a wet sleeve desing is there any problem with the reaurfracing? Thanks
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W164 ML350 CDI
Hi all.
My cousin has a GL 420 cdi that has high pressure in the cooling system. We went to the dealership, they did CO2 test to see if there is any CO2 in the water. They didn't find any. They finally said it might be a head gasket problem. My cousin changed the right head gasket. But unfortunately he still has the problem. He is about to change the left one. Is there anyone here that had a similar problem or that could point us to potential sources for this problem ?
More info:
When we turn on the car, the pressure stays normal. No particular problem. Even after letting the engine run for 5 minutes. When we use the car for a while, the hoses start to be very hard and if we open the water tank's cap, the pressure make water spill out of the tank.
Please tell us your taughts. We are trying to save his holidays with his kids.
Thanks a lot
My cousin has a GL 420 cdi that has high pressure in the cooling system. We went to the dealership, they did CO2 test to see if there is any CO2 in the water. They didn't find any. They finally said it might be a head gasket problem. My cousin changed the right head gasket. But unfortunately he still has the problem. He is about to change the left one. Is there anyone here that had a similar problem or that could point us to potential sources for this problem ?
More info:
When we turn on the car, the pressure stays normal. No particular problem. Even after letting the engine run for 5 minutes. When we use the car for a while, the hoses start to be very hard and if we open the water tank's cap, the pressure make water spill out of the tank.
Please tell us your taughts. We are trying to save his holidays with his kids.
Thanks a lot
Bit of a thread resurrection here; but when you say your cousin changed the right sode head gasket first, but it was the left side that finally solved the problem… you mean in terms of sitting inside the car looking ahead correct?
The right side is the UK Drivers Side, or US Passenger side correct?
Just double checking t see which side is most likely to be the problematic one so I can do extra tests. I know it’s 50:50 either way.
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From: Kelowna, BC
08 GL320 CDI
Replaced the head gasket? What made you think to do that? Milky oil? Oily coolant? Did you run the vehicle with the coolant cap off and look/listen for bubbles in the coolant? Sort of a big task to do a headgasket, just cause you might "think" its a problem.
