Discussion
Jon
When the car is cold how full is the expansion tank?
These cars seam to find there own level!
Try this next time it loses the fluid out of the catch tank, don't refill (Unless it's a great amount) Let it find a level. Then run the car normally and see if it over fills the catch tank again!
If it does then you have a problem which needs further investigation!
Andy
When the car is cold how full is the expansion tank?
These cars seam to find there own level!
Try this next time it loses the fluid out of the catch tank, don't refill (Unless it's a great amount) Let it find a level. Then run the car normally and see if it over fills the catch tank again!
If it does then you have a problem which needs further investigation!
Andy
Jon
Yes I see why you are worried. Give what I suggest a try and see what happens. If it still does it then you have something pressurising the system, which is not good news!
I hope to be at the fest, thanks to the help of friends, so will see you there!
Andy
Yes I see why you are worried. Give what I suggest a try and see what happens. If it still does it then you have something pressurising the system, which is not good news!
I hope to be at the fest, thanks to the help of friends, so will see you there!
Andy
Edited by Mr Tank on Thursday 21st June 14:17
Hi Jon..It could be something as simple as changing the rad cap/caps..If they are not air tight then it will cause the water to boil..Is the thermostat opening fully?..Your fan will come on anyway, On my 280 i can tell that the thermostat is opening when the bottom hose on the rad is getting hot not sure about the V8 set up..Are you getting hot air from your fan heater?..Ziga
I had a similar problem on a previous wedge and it was the expansion tank cap. It should be fitted with a 15lbs cap and one that seals and fits correctly. I got mine from the local spares shop by comparing my old cap and fitting the new cap on outside the shop to make sure it fits. If the spring is weak on your old cap or its the wrong pressure, water will pass out and the cooling system will not work as efficiently. Failing that it could be the water pump, air lock or the head gasket but there is a test you can do to check for exhaust gasses in the water. Try the simple things first and work your way up by elimination. Good luck.
Tony. TCB.
Tony. TCB.
Also check for crud around the expansion cap as this can cause it not to seat properly. The ones I have been selling incorporate a centre valve to allow coolant suck-back (ooh err) when the coolant cools down, but for this to work you must have a good seal at the expansion tank overflow hose.
Also if you have a cap of this type beware that you can also get little bits of crud under the little valve so it doesn't seat properly, and you get leaks. However this is easy to clean - lift up the valve and wipe out the crud with a rag.
Also if you have a cap of this type beware that you can also get little bits of crud under the little valve so it doesn't seat properly, and you get leaks. However this is easy to clean - lift up the valve and wipe out the crud with a rag.
Took some pics of what I mean - bit of crud under cap valve:
Lift it up to clean underneath:
See expansion tank's overflow has a jubilee clip on there to get a nice seal, and the overflow bottle is more than a pint, nearer 2 litres:
(Sorry posted wrong link before... )
Lift it up to clean underneath:
See expansion tank's overflow has a jubilee clip on there to get a nice seal, and the overflow bottle is more than a pint, nearer 2 litres:
(Sorry posted wrong link before... )
Edited by adam quantrill on Sunday 24th June 23:48
Looks like bad news, after trying a new cap and thermostat its still happening but you can take the cap off when its hot and theres no pressure also the water is foaming and bubbling. asked my mechanic and he thinks maybe the cylinder head gasket or even the liners. anyone got an opinion?
jon haines said:
Looks like bad news, after trying a new cap and thermostat its still happening but you can take the cap off when its hot and theres no pressure also the water is foaming and bubbling. asked my mechanic and he thinks maybe the cylinder head gasket or even the liners. anyone got an opinion?
Oh dear i hope not mate..Have you any creamy oil on the dipstick or filler cap?..Is there any water or steam coming out of the exhaust once it has warmed up?, If there is touch it and taste it does it taste sweet?..Remove the plugs and check to see if there is any green or blue tinge to the tips...Is it losing water and you cant see where its going?..Are you able to do a compression test on each cylinder?..Have a sniff in the header tank when hot..(Be careful though)..Can you smell any fumes?..When my head gasket was failing i only had the fumes in the header and then 8 months later the oil was creamy..Foaming and bubbling ..(Small bubbles)..Can be an indication of a failing head gasket...But if the system is not pressurised then it will boil..Fingers crossed for you mate..Ziga Jon, cylinder head is possible as mine went that way on the 350i if your up to it it can be done by yourself just label all the connection, because yours has just happened you should be ok and dont have to get the head skimmed, i ran from home to Ett one year with the head blown and i was told it was ok on inspection.
We'll talk when we meet up at the Fest.
Good luck.
jonny.
We'll talk when we meet up at the Fest.
Good luck.
jonny.
If you can take the cap off when its hot that is independent of the head gasket going. Sounds like you are not achieving pressure in the system, the water will boil in the block without pressure.
So that's the first thing to sort out - why is it not building up pressure? When the cap is on and you heat it up, the top hose coming out of the block should be nice and rigid under pressure. Or else there's a leak somewhere. Run it up to temp with the cap on, then cut the engine, you will hear hissing coming from where the leak is. Nine times out of 10 it's a hose or hose end. But it might be the heater matrix of course... Do your dials steam up at all?
So that's the first thing to sort out - why is it not building up pressure? When the cap is on and you heat it up, the top hose coming out of the block should be nice and rigid under pressure. Or else there's a leak somewhere. Run it up to temp with the cap on, then cut the engine, you will hear hissing coming from where the leak is. Nine times out of 10 it's a hose or hose end. But it might be the heater matrix of course... Do your dials steam up at all?
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