Thanks to info gathered from these forums, especially advises from Sir Xulfiqar, Carsaaz, NFSAAD, Agha 300, Beeberg, Proverbial Slang etc etc (and the list might go on....) and many others, I have managed to steer clear of anything nasty. I am grateful. Running fine on CNG. Was running fine on petrol also, came here on petrol from Khi. There is this one problem that beats me so Im going to lay it out for your comments if possible:-
a. Car was driven to Quetta.
b. Initially gave problem of letting out on fuel suction from tank and the mech lifting pump was changed.
c. New pump had no return line. only in from the the tank and out for the carb.
d. Veh started to stall after prolonged running on idle...like in traffic jams, ques etc. And then it wont start till about 15-20 mins
e. Diagnosed to have a weak pump and mechs wanted me to install another fuel pump, this time an elec pump, as they reckon it is lack of fuel pr / supply due to a weak pump at idle.
f. I disagreed and kept driving it that way avoiding long jams, and long idle running. (Runs smooth on idle otherwise, unless it is sitting and idling for a long time say more than 5-7 mins)
g. Day before yesterday, started giving severe missing on pick up, and just wont smooth out, being perfectly ok on idle as well as revving up to full throttle on neutral, but as soon as i shift into gear and ease out on the clutch, it would start that jerky missing pick, though not staling. Running fine on CNG.
h. Plugs checked ok, harnesses (resistive wires) checked ok, coil checked, ok, point just changed today. After slight adjustments in the timing, the car gave a smooth ride. Afterwards, I let it run on idle for 10 mins. It staled again and the same story all over.
i. New diagnosis by the latest mechanic: need to open up the carb and replace some needle valve kind of a thing. I dont know about its location nor the rationale.
I insist:-
a. Problem is of richer mixture setting. They need to bring down to a leaner setting.
b. The exhaust fumes smell of petrol
c. The lack of a return line in the new pump, plus the richer mixture at idle cause the engine to stall due flooding. An elec pump would exacerbate flooding.
d. I grant the pump might be weak, but opening the carb is frightful as I fear mechs cant put back the 2 dozen vacum lines that have been masterfully connected by my Ustaad of Karachi which has served the car well thus far.
I wish:-
a. Advise on good reliable mech at Quetta.
b. Some rationale as to what may be the likely issues.
c. Encouragement to fiddle with few things myself, should any kind guidance from some guru come along!
Problem:
a. No mech in Quetta wants to come near a charade.
b. I am ready to adjust mixture myself, should some one guide me, though for complete tuning, I lack the required gadgets and am at the mercy of the mechs.