overheating ????

Hi there just wonder if anyone got any ideas

I have a 1991 range rover classic with a 4.0 cross bolted high compression engine which was a new crate engine from rovers in 2000 the engine has done about 50.000 since it was put in. I used the car round town with no problems after buying it then went up the motorway in it and it push the water out the expansion tank. tryed to get it back but top hose blow. so aa truck got it back home heads off cause it had the syptons of head gasket. got the heads skimmed put backed together and run it up all fine in the workshop so up the motorway we go got 20 miles on the motorway and same thing tempertaure gauge started to go up so i pulled of the motorway and the temparure went straight down but did have water on top off the expansion tank. so i drove it back home on the a roads and good as gold. so went down the workshop today and found the heater matrix leaking bleeding it all out all runs fine ticking over. i lefted it today running for about 2 hours all ok drove it round the block all ok got it back to the workshop and was just checking the time timming did not move anything then it started pushing water out the expansion tank but the temprature was only at about half way bit less and none of the hoses was pressuized. it has had a water pump about 2 months ago new thermostats i have check all the coolant pipes there all at the same tempertaure made all the water pipes are clear and the radiator is clear and all is ok i have done a sniff test ok liners ok has anybody got any ideas many thanks man bang his head against a wall ..........

it could be as easy as new top for expansion tank i think thats what i would start with is thin pipe from top of rad to expansion getting hot as it should?

hello the little pipe is but but does keep go luke warm them hot but is getting hotter the more i run it

hi it should be the same as main pipes as it is carrying the water from rad to tank is all the rad getting hot? i think first i would change top then therm also flush rad out look at easy things first to offten we seem to look for the worste lets know how you get on after you change top j

with engine stopped, take the little pipe off and give it a blow through, you can take the o rings off the cap and renew, if you have a suitable o ring kit lying around, the caps arnt expensive so its worth changing anyway!

hello there i used it today not on a long run all the pipes are the same temperture now and it did not loss any water i think i am going to try a cap first and see how i get on just a little silly one when you take the cap off there is not a lot of movment in the expansion tank but i have check every water pipe and there all clear and i have had a hose pipe thourgh the radiator and it seems to be coming out nice and it all clean clear water thanks for your help

are you sure the fans are working?? if its boiling up then its not cooling/circulating properly

Have you tried running it with the cap loose? Also, check the valve things inthe cap and make sure they are clean and working properly. get a small pointy object and push against the pressure valve it should move quite easily.