has my head gasket gone ?

hi all , i have a 205k mile 1996 disco , its been well looked after in the past and since i bought it last month i have been doing a few jobs on it, when i got the car it was a bit smokey apon start up but once it had run awhile this soon cleared , i have just changed the timing belt and oil filter and replaced the oil and air filter , but it still smoked a small bit , however today i used it to pick up lwb series on my trailer and it seemed to be smoking a bit more , a bit of black smoke when under load and whiteish smoke the rest of the time , after about an hour into the trip the temp went high and i stopped to let it cool down but then it boiled over , but we was home by then , after it cooled down i re filled it with water and went out again , after 30 mins the same happened . any thoughts before i pull it to bits . thxs :doh:

sounds like head gasket to me?? but check for coolant leaks first..

thanks red hand , this is my 5th landy all a load of trouble but i love them so what do you do !

from cold run the engine for about 2 minute then turn it off then take off your expansion cap off, if its pressurised then it the head gasket because its not been running long enough to get pressure from heat, only from a combustion leak.

thanks greg , if it is the gasket do i need to to take it off the car to identify which one i need as i think they do a few different types also do i need to change the head bolts ? thx andy

you can see wich type of head gasket it is without tacking head off, if you look down the side off the head below number 3 and 4 injector you can see a small peice of gasket sticking out, there are some holes punched in the gasket 1, 2 or 3. we normalluy fit a 3 hole gasket to all engines, its not that critical. head bolts should be changed after three times of tightening down. some peaople put dot on the top of the bolts for the tightening sequence so its a question of do you think they have been used before. on saying that ive never had a head bolt snap on me and i do at least one head gasket a week. if it is the gasket that has gone i would without doubt get it skimmed.

have run it in the drive from cold , no pressure on cap , can drive for some time before it over heats , also no contamination in the header tank , what do you think

try running it again for 2 minutes again but this time simulte driving conditions by reving it up and down every 20 seconds or so, rev it up to about 3000 rpm. after 2 minutes do the same tourn off check cap for pressure, you will most likley get a small amount of pressure but this will only be a small amount from the fact that it is beggining to warm up . any more is a problem. if you are unsure dont go pulling the head off just yet. start checking other things first. fan belt to start with. when it gets up to temp does your heaters work if they dont then either there is an air lock in the heater matrix, the water pump is not pumping or a blockage. air lock and blockages can be shifted with a hose pipe forced down the long thin metal pipe accross the top of the engine. if all this is ok take the thermostat out check the stat open by dropping it in some boiling water and also take your disco for a run with no stat in. just put a but of silicone on the mating faces on the thermostat housing to help it seal. if it does not overheat then try a new stat. you can also try this, before you take the stat out, take the fan off and go for a drive when it well up to tempreture jump out open your bonnet and feel the radiator it should be hot all over if its not the this can be stuck stat, pump or air. then take stat out and try again, if it is still not warm all over then air or pump try topping up with water and try again if still not hot allover then i would change the pump. just dont use a britpart pump they are crap. hope this is of some help to you, let meknow how you go on.

thx greg , you r a top man , why r landys such a pain , if you cant do the jobs yourself i dont know how people afford to keep these on the road , or maybe its just my bad luck ! thxs for the detailed reply , regards andy

hi greg sorry to be a pain but do you think its poss that the stat could have been stuck shut and it is now ok as today its been on a run and it didnt over heat , the temp gauge reached just under half way and thats where it stayed ,