[bigben2k]

Hi I'm struggling to see if my water systems ok I'm not getting a flow from the return to the bottle like constant flow when running with the cap off I've bleed the system with a coolant bleed and refill kit that sucks all the lines out of air had new thermostat water bottle and still no return don't seem to over heat but no return and when it's operating temp over 90 c my big coolant pipe that goes from the rad to underneath the manifold is rock solid all pipes are hot and heating in the car so can any fellow 335d e90 owners check if there coolant with the cap off when running is getting a return and if there pipes rock solid that goes under the intake manifold the big pipe thanks

[lnxguy]

Sounds like you've still got air in the system.. Drive refill, drive refill. about the only thing you can do.

[bigben2k]

Been driving for hour and pipe still really hard one that goes from top of rad to under the inlet manifold only pipe that seems really hard harder then the rest

[nonford]

My 2 cents. If its not returning AF to your expansion tank, your waterpump is shot. Even with air in the system, it would be spitting back.....pressure will still develop when its gets to temp, thats why your hose is solid...

[bigben2k]

If the water pump is shot would it not over heat just been on 45 min motorway journey or would it over heat if was in traffic and we're im moving it don't get that hot to over heat temps stay from 85-96 max even when side roads and thrashing it im getting bubbles from the return but no flow do you no when the aux heater pumps meant to start as bought a new one and can't here or feel that working

[Tomnavigator]

After you remove thermostat, water pump, radiator hoses, or drain and refill coolant you must purge the system. I know you said you purged the system but do it again with the following procedure. It will hurt nothing and only take a few minutes. Follow the following procedure.

1) First make sure you have the coolant tank fairly full.
2) Run your vehicle for about 5 minutes until radiator hose is too hot to hold.
3) With engine running, look on the top of the coolant reservoir tank and you will see a flat round black plastic screw with a cross head (phillips head). This is the purge screw to vent the system of air. Open the purge screw about 2 turns. This should vent the air out of the system. If and when liquid comes out, close the purge screw to reseat it.
4) Turn off your engine and let your car cool off for several hours until it reaches ambient temperature. The radiator hose will now be soft and cool to the touch. Do not remove the radiator cap on top of the coolant reservoir tank until the car is cool.
5) Take off the coolant reservoir cap and look at the coolant level. If the coolant level is lower, you removed some air from the system. Refill the coolant tank with antifreeze if needed.
Repeat steps 1 through 5 repeatedly until the coolant level does not change when the car cools off. You may have to repeat steps 1 through 5 three or four times to get all the air out of the system.

If the car is not overheating then the water pump is working. You will know this within 15 to 20 minutes. It is very very rare for a water pump to stop working without a major leak somewhere. About the only way a water pump can fail is if the impeller comes off the shaft and that almost never happens or a bearing and/or seal failure. Those failures are obvious.

[bigben2k]

Originally Posted by Tomnavigator

After you remove thermostat, water pump, radiator hoses, or drain and refill coolant you must purge the system. I know you said you purged the system but do it again with the following procedure. It will hurt nothing and only take a few minutes. Follow the following procedure.

1) First make sure you have the coolant tank fairly full.
2) Run your vehicle for about 5 minutes until radiator hose is too hot to hold.
3) With engine running, look on the top of the coolant reservoir tank and you will see a flat round black plastic screw with a cross head (phillips head). This is the purge screw to vent the system of air. Open the purge screw about 2 turns. This should vent the air out of the system. If and when liquid comes out, close the purge screw to reseat it.
4) Turn off your engine and let your car cool off for several hours until it reaches ambient temperature. The radiator hose will now be soft and cool to the touch. Do not remove the radiator cap on top of the coolant reservoir tank until the car is cool.
5) Take off the coolant reservoir cap and look at the coolant level. If the coolant level is lower, you removed some air from the system. Refill the coolant tank with antifreeze if needed.
Repeat steps 1 through 5 repeatedly until the coolant level does not change when the car cools off. You may have to repeat steps 1 through 5 three or four times to get all the air out of the system.

If the car is not overheating then the water pump is working. You will know this within 15 to 20 minutes. It is very very rare for a water pump to stop working without a major leak somewhere. About the only way a water pump can fail is if the impeller comes off the shaft and that almost never happens or a bearing and/or seal failure. Those failures are obvious.

Thanks Tom would the pump that is for the heater aux pump cause this issue I bought a brand new one but never herd it running does it run soon as the engines running or is it at a certain temp it comes on I put 12 volt to it and it's works but never herd it running at all not to sure what turns that little pump on thanks for the advise never had a car be such a pain to bleed

[Tomnavigator]

The aux pump should not cause an issue like you describe. I don't think you have any problem other than possibly air in the system. Here are my reasons.

1) 99+ percent of water pump failures are related to bearing failure (shaft wobbles as it turns) and seal leaks (caused by shaft wobbling as it turns). Usually the bearings start to go bad and then the shaft wobbles. Once the wobble gets bad enough the seal then leaks and you see antifreeze under the car when you stop. Impeller issues and gasket leaks are the other <1 percent of failures. Most people will never see these issues in their lifetime.
2) The system is supposed to build up pressure up to 10 to 15 psi as the engine heats up. That is why you are never supposed to open the reservoir cap when the engine is hot. This pressure build up will cause the hoses to feel hard. This is normal.
3) You can see the antifreeze circulating in the reservoir tanks on some cars. But, not on all.
4) Your car would overheat A failed water pump would cause overheating and you would have serious issues in less than 40 minutes of driving.

Your method of pulling a vacuum on the system when you refilled the antifreeze is good and should have removed the air. If you want to be careful, then purge the air as per my earlier post. If your method of pulling a vacuum on the system was effective, no antifreeze will be needed. also, If you have already driven the car several times and let the car cool down completely since your work on the car. Then the car probably purged the air out of the system into the reservoir tank already. Just check the level and refill. Drive and don't worry about it. Just check the level several more time and keep the tank at the top level. Check and refill as often as needed until it never needs more coolant. The air will be out of the system. Once you get to this point, sleep soundly and stop thinking about this and go back to checking coolant levels every few months like everyone should do.

[Tomnavigator]

bigben2k,
I really think you don't have any issues. I think you are just being careful which is good. I'll address statements from all your posts.

First post. You don't see coolant flow in all cars in the reservoir. Your temperatures are running right where they should which indicates no issues. All hoses are hard is normal. All hoses should be about the about the same hardness since they are all connected together. Wait until the car cooles down completely and feel the hardness of all hoses. Some will be harder than others because of age, design, etc. This is normal. Smaller hoses usually feel harder than larger hoses.
Post two - read my comment above about hose hardness.
Post three - You are right if you had a problem your car would have overheated within 40 minutes. 85 degrees is a tad low 90 is right for warmed up engine. bubbles are just the last bit of air being purged from the system. This is normal.
Fourth post - 335D in the US does not have aux pump. However, aux pumps are typically used to keep the interior of the car warm when the car is turned off so you will return to a warm car instead of a cold car in the winter. Aux pump failures usually do not cause overheating if it fails. It is called an auxiliary pump because it is not required. The water pump of the car circulates water to the heater when the engine is running and the aux pump is not needed. The aux pump only runs when you ask the car to keep the car warm after you shut off the engine. they typically run for about 30 minutes and shut off. Look up the use of the aux pump in the owners manual.
Your car is fixed. Stop worrying about it. Just refill the coolant as needed until the last little bit of air is removed from the system. Then drive and forget.

[bigben2k]

Originally Posted by Tomnavigator

bigben2k,
I really think you don't have any issues. I think you are just being careful which is good. I'll address statements from all your posts.

First post. You don't see coolant flow in all cars in the reservoir. Your temperatures are running right where they should which indicates no issues. All hoses are hard is normal. All hoses should be about the about the same hardness since they are all connected together. Wait until the car cooles down completely and feel the hardness of all hoses. Some will be harder than others because of age, design, etc. This is normal. Smaller hoses usually feel harder than larger hoses.
Post two - read my comment above about hose hardness.
Post three - You are right if you had a problem your car would have overheated within 40 minutes. 85 degrees is a tad low 90 is right for warmed up engine. bubbles are just the last bit of air being purged from the system. This is normal.
Fourth post - 335D in the US does not have aux pump. However, aux pumps are typically used to keep the interior of the car warm when the car is turned off so you will return to a warm car instead of a cold car in the winter. Aux pump failures usually do not cause overheating if it fails. It is called an auxiliary pump because it is not required. The water pump of the car circulates water to the heater when the engine is running and the aux pump is not needed. The aux pump only runs when you ask the car to keep the car warm after you shut off the engine. they typically run for about 30 minutes and shut off. Look up the use of the aux pump in the owners manual.
Your car is fixed. Stop worrying about it. Just refill the coolant as needed until the last little bit of air is removed from the system. Then drive and forget.

So issue with not getting a return was down to me buying a water bottle of Amazon took return pipe off and was getting a good return flow in the pipe bled the system again let it cool after a 30 min drive and topped up the coolant and got the last little bit of air out was fine for a bit with the cap off good return flow coming into the bottle now I've noticed white grey - blue smoke coming out a friend of mine said don't smell like burning oil smells like coolant now I'm wondering if the Headgasket had gone like a small brake from compression side into the the water ways the pipe from the rad on the top right hand side looking at the engine from the bonnet that goes underneath the manifold straight above the glow plug module is rock solid lot lot harder then the rest so I've ordered a head gasket sniff test to see if any emissions is in the system to rule this out as never had car so hard to get the air out fingers crossed Headgasket is not gone

[bigben2k]

So bought a Headgasket c02 tester to see if head gaskets gone and head gasket is gone the test after 1 min when hot turned the liquid green meaning Emissions found in the coolant system so looks like Headgasket has gone or cracked head makes sense on why the coolant had pressure in it and was never bleeding out properly so head is coming off to see what gone wrong thanks for all your help will update u as going

[BB_cuda]

From Tomnavigator's post #6

3) With engine running, look on the top of the coolant reservoir tank and you will see a flat round black plastic screw with a cross head (phillips head). This is the purge screw to vent the system of air. Open the purge screw about 2 turns. This should vent the air out of the system. If and when liquid comes out, close the purge screw to reseat it

I have never touched the bleed screw. Mine always pees a small stream and never had a problem.

Is there a reason to reclose the bleed screw?

[bigben2k]

#update Headgasket or cracked head caused the system to keep pressuring up in the coolant so bought a 535d 2005 engine with turbo bigger injector tip from darkside tuning in the uk r90 fuel pump Egr delete swirl flaps delete and was meant to have hybrid turbo Cores but there not thing is the turbo is completely different than my 335d 2006 engine I bought was a M57T E4 and the one that was in my car was a M57TU what's the difference in engine I no the AC pump is different and the power steering pump is the older type but my 335d stuff will fit straight on are the internals of both engines the same all was worried about can anyone shed some light on what's different thanks

[Tomnavigator]

BB_Cuda,
In my opinion, The bleed screw should be closed. The coolant system is designed to be under pressure. Most vehicles are designed to run up to 15 psi pressure. When you put liquid under pressure it raises the boiling temperature of the liquid. This means the coolant boiling temperature is raised higher than it would be at atmospheric pressure in a system operating under pressure. The boiling temperature of coolant in a car is around 250 degrees under normal operating pressure. I read somewhere that every pound you raise the pressure the boiling point of the coolant goes up 3 degrees (rough ball park). Our car thermostats keep our cars at 90 celcius which is 194 degrees fahrenheit. However, there are localized areas of the engine block that are much hotter. You do not want these localized areas to form steam. Any area where steam forms will cause significant temperature rise of that spot because steam does not cool as well as liquid coolant. Because of this, the coolant systen is designed to run under pressure to raise the boiling point of the coolant to a level that steam will not form anywhere in the engine.
Closing the bleed screw will cause your coolant system pressure to rise to the designed pressure and will reduce the chance that your car will overheat since the water antifreeze will boil at a higher temperature. The pressurized system will also reduce the chance of localized hot spots in your engine which could cause warping.
I know you said you are not having any problems. But, I would close the bleed closed and run the coolant system at designed pressure. I don't know of any vehicle designed in the last 70 years that runs the coolant at atmospheric pressure (bleed screw open or radiator cap vented). They all run at a pressure of around 15 psi to prevent hot spots in the engine.
Every manufacturer in every country of the world runs pressurized coolant systems for the reasons stated above. This is one thing every manufacturer agrees on.

[bigben2k]

Little update so the 535d engine I bought to swap in the 335d e91 is a no go blocks different and engine mounts from the 335d don't fit the 535d engine so took my 335d engine apart and pistons don't look to bad the bores you can still se the original honing marks can't seem to see if the head gasket was the issue as if I'm honest not done many to to no what I'm looking for going to get the head pressure tested and skimmed if it's ok and then rebuild the head and new timing chains and clean up then fingers crossed no more coolant issues and no white smoke

[BB_cuda]

Originally Posted by Tomnavigator

BB_Cuda,
In my opinion, The bleed screw should be closed. The coolant system is designed to be under pressure. Most vehicles are designed to run up to 15 psi pressure. When you put liquid under pressure it raises the boiling temperature of the liquid. This means the coolant boiling temperature is raised higher than it would be at atmospheric pressure in a system operating under pressure. The boiling temperature of coolant in a car is around 250 degrees under normal operating pressure. I read somewhere that every pound you raise the pressure the boiling point of the coolant goes up 3 degrees (rough ball park). Our car thermostats keep our cars at 90 celcius which is 194 degrees fahrenheit. However, there are localized areas of the engine block that are much hotter. You do not want these localized areas to form steam. Any area where steam forms will cause significant temperature rise of that spot because steam does not cool as well as liquid coolant. Because of this, the coolant systen is designed to run under pressure to raise the boiling point of the coolant to a level that steam will not form anywhere in the engine.
Closing the bleed screw will cause your coolant system pressure to rise to the designed pressure and will reduce the chance that your car will overheat since the water antifreeze will boil at a higher temperature. The pressurized system will also reduce the chance of localized hot spots in your engine which could cause warping.
I know you said you are not having any problems. But, I would close the bleed closed and run the coolant system at designed pressure. I don't know of any vehicle designed in the last 70 years that runs the coolant at atmospheric pressure (bleed screw open or radiator cap vented). They all run at a pressure of around 15 psi to prevent hot spots in the engine.
Every manufacturer in every country of the world runs pressurized coolant systems for the reasons stated above. This is one thing every manufacturer agrees on.

We are perhaps refering to a different bleed screw. I went to another forum and asked folks there if internal to their reservior do they see the very small stream continuing to flow (pee as i call it). They all replied that there isn't a way to completely shut this flw off and you will likely break the bleed screw trying to do so. My car came from Munich with it doing this so I'm leaving it be. It doesn't over heat..
My radiator hoses get very hard when up to running temp so I'm confident the system is at proper pressure.
None the less, thanks for looking out for me.