1999 E46 BMW 318 losing water

[WEHGuy]

Hi, I'm having a problem with water leaking. I have replaced the thermostat, expansion bottle and some of the surrounding pipes. Sometimes the coolant light will come on after only 10 miles and need water other times I can do 100 miles before I need to put water in it. It never overheats. When I bleed the system it seems to last longer before the coolant light comes on again. It seems to be getting air blocked as well. I have been told it could be the head gasket but, there is no oil in the water, no water in the oil and no lack of power. I have also been told it could be the heater matrix. The windows always steam up unless the windscreen heater is on but, none of the carpets are wet or even damp. It sometimes has a drip at the back of the engine but, I've been told that is the Air Con but, it has coolant mixture and not just water. CAN YOU HELP? Thanks in advance

[< FORZA WEST]

Several issues with the M43tu engine -

1,Head gasket failure cylider number 4 to coolant jacket.
2,pastic water distributer at rear of cylinder head cracks
3,thermostat housing cracks (already done).
4,Radiator bloats and splits in the lower third.
5,Expantion bottle splits at top.
6,rad cap fails to hold any pressure.

With 2 - 6 its worth having the head gasket checked for failure (block test) as they are all symptons of head gasket failure.
Head gasket failures arent always obvious.

Sometimes the water pump fails or leaks.
pipe from rear water distributor to inlet manifold splits.
rarely the heater matrix and if it was at fault it would smell of coolant in the cabin

Edited by < FORZA WEST on Friday 27th November 21:34

[WEHGuy]

What's the cheapest way to get it tested for head gasket failure?

[< FORZA WEST]

Block tester..Easy to use and used at specialist/dealer level


http://cgi.ebay.co.uk/BT500-TEST-TOOLS-BLOCK-TESTE...


You may have to do this test several times as the engine warms unless it turns yellow straight away.

[WEHGuy]

Also it seems to lose water quicker when driven spiritedly(if thats even a word?). Also for only the 2nd time tonight I heard a hissing noise coming from the engine. I think there was water coming from on or 2 hoses at the back top of the engine. It looked like the hoses were coming from the cabin. What could they be? Where can I get the blueprint for the engine? Thanks again for taking time to help me.

[< FORZA WEST]

The 2 hoses from the baulk head are from the heater matrix...one then goes around to the rear of the cylinder head water distributor. And the other to the water valve down on the inner wing.

All parts can be found on realoem.com

[WEHGuy]

[quote=< FORZA WEST]Block tester..Easy to use and used at specialist/dealer level


http://cgi.ebay.co.uk/BT500-TEST-TOOLS-BLOCK-TESTE...


You may have to do this test several times as the engine warms unless it turns yellow straight away.
[/quote]

I have ordered this. Is it pretty straight forward to do?

[WEHGuy]

WEHGuy said:

[quote=< FORZA WEST]Block tester..Easy to use and used at specialist/dealer level


http://cgi.ebay.co.uk/BT500-TEST-TOOLS-BLOCK-TESTE...


You may have to do this test several times as the engine warms unless it turns yellow straight away.

I have ordered this. Is it pretty straight forward to do?

Well I have just used that and it didn't change colour. What should I do now?

[WEHGuy]

Does anyone have an idea where else I could post this to get a better response? It's seems to be sucking air into the coolant system and gedtting air locked. Any suggestions? Thanks in advance

[crusher]

i have had the same prob with mine...i traced it back to the rubber seal on the plastic water pipe on the rear of the engine block...replaced the coupling and the seal at the same time,two bollts out and t it all comes away.... bled and its all good now....took about an hour all in...as a previous poster said the piece can be seen clearly on oem and apparantly is a very common prob on this model...bit tight to work on but easy enough
good luck

[WEHGuy]

crusher said:

i have had the same prob with mine...i traced it back to the rubber seal on the plastic water pipe on the rear of the engine block...replaced the coupling and the seal at the same time,two bollts out and t it all comes away.... bled and its all good now....took about an hour all in...as a previous poster said the piece can be seen clearly on oem and apparantly is a very common prob on this model...bit tight to work on but easy enough
good luck

Hi, thanks for the advice. Do you have a blueprint showing where they are? Thanks in advance