DONK TROUBLE

[pootrol]

this has nearly beaten me.my TB42 is running rough.its in the process of being cleaned up.its had to go through some big changes from how i got it to get it close to standard again. it has new coil,resistor,condensor,carb,pump,leads,plugs,points,cap,rotor button.ive checked to see if the timing marks are true top dead and set timing ,checked voltages to diz and coil.earthing seems to be alright.when i go to throttle it ,it gasps pops out the carb and either will stall or rev.if it revs it just pops and bangs out exhaust.it did run sort of allright before all the new bits went on.does idle not to bad but you can detect it aint right.have swapped leads and coil back to old ones to see if any diff.........none.pulled rocker off to see all valves moving,checked clearances.would a manifold leak have signs like this.this vehicle apparently sat in some ones yard for a year before i got it.it was duel fuel when i got it but know is just petrol so if the dizzy got tweaked for gas would it affect my timing if i tried to set to factory now.......................

[hulsty]

done a compression and leakdown test?

burnt valves maybe? are all the mixture settings correct? carb could be up shit creak if it was sitting for so long

[InSanE]

sounds like a timing issue mate first thing to do is check your firing order as you may have put a lead in the wrong spot, then make sure you put the dissy in the right way and double check your point gap then try starting it with the dissy in different positions, if that fails check your valve clearances and see how you go there.

[xenith]

sounds like a valve burnt out or to close on the tappet adjustment mate

[pootrol]

say for example i have an intake and exhaust not shutting properly or burnt out.this would explain the popping at revs but would it say pressurise the intake too explaining the back firing through the carb.if this pressurising thing is possible it would counter act the suction of fuel from idle to revs explaining the huge dead spot when i want to give it some throttle. just me thinking out aloud.this all happened around when i changed the oil from black water to new golden fluid.is there any hydraulic pump up parts in the valve train.this may explain something as there was 1 0r 2 valves i adjusted.the carb is new and i trust the fella who built it to a certain degree...............

[skippy's GQ]

Could be burnt points,( even thow u did renew them , but dont rule it out) ore point gap is wrong, also could be carbie or te timming set wrong, carnt really be sure with out hearing or seeing it!!!!

[pootrol]

ill check the points.i had to clean the new spark plugs as they where black as from when i was running it before the carb rebuild it ran really rich charfing black sh%t from the exhaust...............

[xenith]

sounds like a intake valve readjust all mate