V8 pourng water...when it feels like it.

[beattiedh]

Hi Al little advice please.

92 J 3.5 EFi

Has been drinking water but rather irregularly.

Some times the water runs dry and other times not. Have had the thermostat out and relpaced with new gasket. Rad has been out and washed through. hoses reconnected.

It seems that after a run of more than 10 miles and when stoppped after about three mins water starts to pour down on to the floor. When I have looked under the bonnet there seems to be a bit of a small lake in the V between the cylinder banks.

As far as I can see there is nothing leaking around the engine. Does water go through the plenum chamber? Could it be a hose at the back of the engine?

Anyone had this before or got any advice?
thnaks

Duncan

[drmike]

When you say water pours out - do you mean from the expansion/deader tank? If so it sounds like the system is pressurised and a head gasket has gone.

When the engine is up to tempretaure after a run feel the hoses. Are they really hard and obviously under pressure or just firm? If really hard then head gasket sounds likely.

I had this and was thoroughly depressed but it's not too terrible a job even for a duffer like me. I took the usual advice and had the heads skimmed and was lucky as a local bloke does them 25 quid each.

I would guess that the water in the valley is just leaking from somehere as it's under pressure.

Incidentally, I saw no oil in water or water in oil and yes I could see bubbles in the radiator if I squinted down the filler plug especially if I raced te engine.

On the other hand I hope it's not this and is something simple!

Mike

[beattiedh]

Hi Mike

The water comes from the back of the engine it seems and not every time. It does seem to be quite random.

There is no contamination either way in terms of oil and water.

The hoses are firm but not rock solid.

Going to try and have a deeper delve today.

Duncan

[Skippy]

Just out of intrest, do you run LPG?  As sometimes the installers splice into the heating system behind the engine and i had a similar problem to you with the water leaking from this join into the valley area.

[Range Rover Blues]

The coolant runs through the inlet manifold so if the gasket (read piece of tin) leaks you will get a puddle under the inllet ie the valley as you describe.  Also there are the coolant hoses to the heater running behind the engine as Skippy said.

The boiling over you describe could be caused by a loss of coolant on the previous journey, lowering the coolanat level and preventing the natural circulation of coolant as soon as the engine stops (more improtantly the water pump).
After stopping the coolant actualy heats up as heat soaks from the engine, the underbonnet temp rises for typically 30 minutes.  Normaly the coolant will circualte slowly by 'gravity' ie hot coolant rises.  This may expalin why it only 'blows off' sometimes.  You could also be getting airlocks which only make things worse.

It's important you re-fill the engine via the small plug on the top of the engine, fill it fast to prevent air getting trapped in the heater matrix.  Don't fill it via the header tank.