2001 318i M43 Cooling water problem

[Ricky318i]

Hi everyone

Please advise: I just got back from helping a friend get their Pre-Facelift 318i started. M43 1.9L. Got it running.

Disconcertingly, there is a large amount of cooling water that is being lost daily with no idea of where it is leaking. No visible leaks under the car, no temperature increases and no steam coming from the engine bay or expansion tank.

Anyone has any ideas? :mmm:

 

[Jandre]

My 318i lost a lot of water on a daily basis after the engine rebuild. Also no sign of where it is going. When we did a pressure test on the cooling system, we found a leaking waterpipe at the back of the engine. Try a pressure test on the cooling system first.

 

[Ricky318i]

I also suggested a pressure test.

 

[Billy]

I drive a BMW 318 E46 2003, Model experienced the same problem with the coolant, losing water but with no leaks or anything, took it in for inspection at work-shop, they claimed to have fixed a lose pipe drove the car for a day or two same problem ..to cut a long story short, I eventually checked the coolant and guess what, it wasn't properly closed it was tight ande everything, but it wasn't turned to it maximum, it still had about 4 or so turns left, it was hard to turn it further but the more I tried the easier it turn up until a gap which was visible from where I was standing was completely covered and guess what, never had any water loss ever since, maybe it was just my luck but ya that's what happened to me ..try that as well or before you turn the cap you need to "bleed" the coolant for any air locks. :thumbsup:

 

[Ricky318i]

thanks I'll hear what the outcome was. but I also suspect a leak in the tubing, although a possible leak in the head due to crack is still a possibility.

 

[Major]

My 318i lost a lot of water on a daily basis after the engine rebuild. Also no sign of where it is going. When we did a pressure test on the cooling system, we found a leaking waterpipe at the back of the engine. Try a pressure test on the cooling system first.

I'm missing something here. You had no signs of water on the ground, steam, nothing, but a leaking waterpipe was the problem? Wouldn't a leaking waterpipe leave a trail of water?

 

[zaleonardz]

On the V motors, does it not collect in the valley pan and then burn off?

I am also loosing some coolant, but minimal.

Will need to take the intake manifold off and all other bits off, but will do that when I do my PCV as well.. another fun DIY coming up.

 

[///M_POW]

Will need to take the intake manifold off and all other bits off, but will do that when I do my PCV as well.. another fun DIY coming up.

Since u like DIY's got some for u ...

Power steering fluid flush...
Clean the O2 sensors..
etc, etc

 

[Jandre]

Not a single drop of water in sight Major. Not even when standing overnight. Nothing. When we pressurised the cooling system, we could hear it dripping onto the manifold and boiling away. Then we could see the water as well. Ever since we replaced the pipe, my water level remains constant.

 

[zaleonardz]

Power steering one is easy.


There is a 8mm(I Think) hex nut right underneath the power steering pump, take it outlet most of the fluid drain out.

Lock steering left to right a few times, if you have a hydraulic braking system (H31), pumping the pedal 20 times until the bomb or brake accum is emtpy.

You will get about 1.1l out and seeing though that the system takes about 1.2L (the E34 at least), you will get most of it out.

The O2 sensor one I havnt tried yet, will let you know sometime soon

Will need to take the intake manifold off and all other bits off, but will do that when I do my PCV as well.. another fun DIY coming up.

Since u like DIY's got some for u ...

Power steering fluid flush...
Clean the O2 sensors..
etc, etc

 

[Ricky318i]

Since you're clued up about power steering: What is the normal working pressure of the Power steering system? My cap was tightened properly, so i saw some fluid leaked out.

 

[zaleonardz]

What car.

However I do not think the cap/res will be under too much pressure, the pump I know is 100+ of PSI, it is really strong pressure, but the res will be substantially less.

Also remember that in some cases you have "accessories" on the power steering, such as brakes on certian cars (E32's, some E34's...) as well as if you have self leveling rear suspension, all of this is driven by power steering.

It does however make sense that an untightened cap will have some discharge. Its actually the oddest things, on cars with the H31 brake system, when you release the brake, it actually returns power steering to the res, so brake in fluid goes down, brake up fluid returns, had me confuzzled for a while.

 

[Ricky318i]

it is an E46. Yes the cap was not tightened properly, and now i see there is no more leaking. I first was a bit worried.

My steering seems to be all in order. although i might have to have the brake fluid and power steering flushed maybe next year. According to me it is been there since new.

 

[Chatsubo]

My 2001 318i (non-f/l) went through a whole bunch of coolant leaking problems. It'd take 2 weeks to get to the "warning light" stage. This was from the time I bought the car. I took it back to the dealer who sold me the car two times, and it was "fixed" two times, but no resolution - it still was loosing coolant just like before. Then I took it to a BMW dealer (Club motors Randburg), thinking atleast if I pay the pro's this'll get sorted, right? I took it there two times, and a WHOLE bunch of replacing random shit later (and massive bills), still the car was loosing coolant at the same steady pace. So I said these guys, they're just ripping me off......

I then got the name of an independent ex-BMW meccie from a friend of mine, and took the car there. Literally 1 hour later he called me and said the problem is solved.... He'd tightened a loose clamp, no charge.... And thus, my saga ended, and the car was perfect after that. I still mourn the amount of pocket I lost on the dealer.

 

[Ricky318i]

thanks for the info. I also assume it's something similar. ..

 

[318droptop]

hi ricky i have the same problem. i will check the cap. but wich clamp was loose that eventually sorted out the problem.

 

[Ricky318i]

I haven't checked out what was the outcome, but will report back. now that Freerider has reported a leaky radiator, I'll have to evaluate that as a possible culprit

 

[koos12]

Leaky radiators are one of the problems with these cars. Hot and cold cycles running. A lot of times you cant see the leak as it is right at the bottom of the radiator. Check in the bottom corners of the radiator they love to leak there. A new radiator is about R1400 with installation. Also check the pipe at the back of the motor if you remove the pollen filter you will be able to see it. Behind the oil filter next to the engine block there is another water hose and fitting use a torch and check that one out as well. Check below that for any water residue. Guess your water pump and the 2 front hoses of the radiator is fine otherwise you would've seen water. A lot of times the water leak from the radiator onto the fan and gets blown away. If it was a gasket problem I'm sure you would've seen white residue on the dipstick, oil cap or at the exhaust. Also check the bleeding valve and the cap.

 

[HotboX]

howzit guys, i have a 2000 318i e46. had numerous coolant problems and they just dont stop. changed the radiator once, coolant bottle twice, thermostat twice and water pump once. and im still losing water but no water trail. the warning light comes on after about 2 weeks. i have the same problem as you. id like to know what it is, im going to do some research. good luck.

 

[Ricky318i]

This is not to scare anyone, but it could be crack in the water jacket and the water leaks into the exhaust. Will never be noticed, until it's too late.