accept my congrates on buying a car..
you dont need to change the radiator water after 500km or so..
just maintain the Water level.
do check ur radiator on daily basis..
check Engine oil level wkly .
and notice your engine for leakages frequently.. coz leakage is the only cause leads to droping engine oil level or gear oil level...
check Break fluid wkly....
change ur engine oil after 2500km along with oil filter and Airfilter ( changing of air filter is conditional,depending up existing Condion )
dont let ur Car over heated ever......for that you need to keep an eye on your speedometer for Temp.Guage..
if Your temp guage exceeds normal level,it can damge the gas Kit..
gas Kit For mehran is Very Unreliable..
in morning... let your car start for 5 min without pressing throtle.
if ur car is old one with cng kit installled...
then you must Check life of your Gas cylinder.
if its inspection date is near.. get it done as soon as possible
thats the most important thing to do..