4.0 V8 using coolant

P38 owners.. min's a 1995 176000 miles with engine overhaul at 122000 miles. I am sure you have all seen this before, but for my sake can anyone help!

The coolant level is dropping quite quick, about 1 pint in 100 miles. There are no bubbles in the expansion tank and no deposits in/on the oil. Carpets are all dry but the top hose does feel very hard as the engine heats up. It is not rock hard but a bit stiff. Maybe it should be. Very very little water is returning from the tiny pipe to the top of the tank. It runs mid temp on the guage and no overheating. When hot the tank level is pretty high and if I dare, as I did to remove the cap, water pours out everywhere at a rate of knots!

What else can I check and what will the checks tell me.?

Help

HI i would check that your expansion bottle is not blocked there are 2 jets but you can only see the top jet spray when you rev it and it should be a good spray,top hose sounds like it is pressurising and it will flow out the top if pressure is to much best check that water flow first,tiga

Well spotted! Disconected pipe and loads of suff come flooding out. Then with a drill bit by hand drilled out the rest in the tiny expansion bottle tube and with a wire cleared out the tiny hole.

In checking, let it run for 10 mins, already hot and when released cap very slowly loads overflowed. Is this right?

Also, pressure in pipe still seems pretty hard!

More thoughts?

Ps Why would the blocked pipe cause water loss? Also will not know for a few days if that is what it is!

hi the blocked pipe will not cause coolant loss but it will cause loads of pressure possibly causing head gaskets to blow or worse still pourous block, but this is not so common on the 4.0 litre hope this helps tiga,i have seen stuff advertised on ebay claiming to seal any water leaks plus engine internal cracks cost was about £30.00 so could be worth a go.

Great help thanks. I have added the K Seal to the coolant and we will see. I checked it tonight and the top hose seems pretty hard! I left it for about 10 mins and checked again and still very hard. Could the cap be faulty? The pressure seems far too high, should the cap not be letting go! I have nothing to compare it with but it seems a bit high. If it was a porous block would it not allow pressure to go back through block? Thus relieving it quite quickly? Thoughts?

HI know if it is a pourous block it will keep the pressure on as it compresses the cooling system,cap should go at between 12-15psi sorry cant give much more advise apart from getting it block tested but this will only tell you if head gaskets or pourous block either way you will have to remove heads to inspect,tiga