328i problems.

[ftt]

Hi There guys. I hope someone can assist me. I drive a 1996 328i. Every morning I have to open up the waterbottle cap so that air can excape and I sometimes need to fill up with anti freeze. It builds up pressure as i'm driving. If I drive to 3000rpm and change then it seems ok. But as soon as I open her up the pressure builds up hectic... I know its normal for the cooling system too build up pressure but how is air getting into the system? I already had to replace a radiator because the pressure caused it to fail. A friend told me he suspects a cracked head. Theres no water mixing with oil and no water or oil leaks either.

Has anyone had a similar issue?

Thanks

 

[zaleonardz]

Airlock ?

Thats an odd one, I am not soo sure about the cracked head though, that would release pressure and should cause some kind of leak depending where the crack is on the head. , and if your loosing that kind of compression, you would feel it in the motor.

Im really guessing here, no overheating/running hot ?

sheesh, good luck fixing it man, keep us updated.

 

[e46jase]

get a compression test done to see if its the head or not im busy doin my head gasket as we speak and for months i was loosing small amounts of water an topping up abit evry week also couldnt see water in the oil or visa versa, bm's hav issues with there cooling systems so you could b loosing water from expansion tank/ hoses /water pump . sounds to me like you have a small leak somewer i doubt ur head is cracked unless u or previous owner has ever overheated the car. i overheated awhile ago an drove around with head gasket gone for ages jus lossing a little bit of water a week without traces of water in oil then bam alla sudden one day car ran terribly and could see the water in the oil
hope you find the problem good luck man

 

[STREETRACER]

it can even be an blown head gasket between water port and cylinder then you will not nesecerly "spelling" get oil in your water or otherwise! but like zaleonardz said mabe just an airlock! do you just fill it up with water or do you properly bleed your cooling system?? also there was a problem with pre '96 E36 models with water pump!! they came out with an ceramic platic propeller and need to be changed to metal!! they gave lots of crap!! bought a metal one from BEMOS for R400 for my brothers E36 325I!!
BMW realy needs to be abused before they crack their heads!!!! Have you noticed how long they take to cool down? that is bmw's design to keep the engine fit! it heats up slowly and cools down very slow! that avoids cracking etc...
good luck and please keep us updated if you find the problem!! :thumbsup:

 

[Ricky318i]

sounds like your cooling system isn't bled properly. perform a bleed.

 

[ftt]

Thanks for the reply guys.

Car doesnt overheat at all. Provided I check the water in the mornings. The only time it did overheat was when the air buildup in the cooling system got too much and water was forced out of a hose. I didnt notice as I was driving so I lost quite a bit of water and the car overheated. Since then I've been keeping a close eye on it.

STREETRACER - R400 is nothing for that waterpump. Where can I buy one?

 

[Leon328]

If you experience the same issue after bleeding the system then I think you might have the same problem as I had on my E36 325.

It overheated on the highway and afterwards kept on building pressure in the cooling system. I had a cracked water jacket on the number 6 cylinder exhaust port.

Good luck.

 

[ftt]

Yup, I suspect as much. Thanks Leon328
I will keep you guys posted.