you say SMOKE coming out of dash , whereabouts in the dash ?.
left hand side [from inside cab] and fixed to bulkhead is the heater matrix and blower , if youve overheated engine or have leak in heater hoses or matrix you may have had steam coming through the bulkhead holes .
the radiator header tank is on drivers side , again if overheated or too high a level in the tank you may have had excess water come out of the overflow pipe, possibly as steam and this is what you saw .
trying to pull a dead weight out of ground will probably make youre clutch slip , you may or may not smell anything , but it sounds as if youve been pulling hard in a low gear and of course the power of engine in low gears through the clutch is fairly fierce , enough to overcome the clutch .
you may have a slight oil leak from youre rear main bearing oil seal , this is at rear of crankshaft and inevitably the oil deposited will get onto youre clutch . if the clutch gets hot then the oil will burn or vapourise off it , this seems the most logical solution to what you experienced .
are you sure it wasnt a case of youre wheels spinning and thats where the smoke came from, have you ever been to santa pod drag racing , if you have youll know what a burnout is !!>
if you have smoke coming from the engine breather/filler cap then thats blowby , caused by "gas" getting past the piston rings each time it compresses .
normally youre crankcase wont pressurise itself , it will allways have a vacuum , but with blowby it will more or less be pressurising the crankcase .
make sure that the filler cap is cleaned so it can pass air through its filter .
a common sign of a blown headgasket is a white mayonaise type deposit seen inside the rocker cover [thru filler cap hole] , this is made up by the water/steam expelled mixing with the engine oil , but it isnt allways a sign of blown gasket, some engines will have this deposit in for other reasons , ie like if not used often and they get damp often .
if you take the filler cap off and there is a lot of smoke coming out then you have 2 options really. if the engine runs ok and you can put up with it , then carry on using it as it is .
or you replace parts and rebuild the engine . if youre landrover is a turbocharged engine , especially a 19j type , then it may have cracked pistons , this is common on these type engines, pistons crack in the dome on the top across them . but usually this means smoke out of exhaust etc .
the problem could eminate from the turbo itself and oil is getting into engine via leaky seals and thus being burned with the fuel mixture , but that would be unlikely to show any smoke other than out of exhaust , unless of course you have hole in exhaust under ther floorpan.
if filler cap was loose when you investigated problem , it may only be that oil has been thrown out of the filler cap hole and has got onto exhaust and burned, thus you got smoke in the engine bay from the unburnt vapourising oil .
clutch slave cylinder commonly fails on range rover classic and 90 landys , due to it being next to the exhaust downpipe ,and only having one piston washer ,this usually starts with a small leak of hydraulic fluid from the cylinder and then eventual failure of the slave cylinder. you can tell its about to happen when youre clutch pedal all of a sudden goes to the floor and then a few pumps later or overnight the pedal comes back to life .
not that the clutch cylinder has much to do with smoke coming out of it but if it is leaking a little then the hydraulic fluid may get onto the exhaust pipe and burn or it may enter into the gearbox bellhousing and get onto the flywheel/clutch . when you got the clutch hot the fluid will have started to brun off it . gearbox bellhousing is directly under centre of cab so is in right place .
check you dont have any fuel leaks from any pipes , especially the diesel return pipe from the injector pump going back down to tank , the pipe can rub on the bulkhead or fittings and wear thru , thus drips of fuel which can get into anywhere underneath dashboard area .
theres a lot here to think about , its most likely not serious as such , but after having my own diesel 90 for a few years and also various models of landrover and range rover i got to know some of the more common problems that occur , which are allways the hardest to spot but simplest to fix .
i do my own repairs and mechanics , being in that type of job for the last 20 years .
theres nothing magical about a landrover , theyre all built like tractors and can be worked on as easily , thats why so many people opt for them instead of the other rubbish out there .
mind you they do last twice as long as the competition .