So if you open throttle really quickly it picks up revs ok? But slow throttle openings are bad? When you open throttle quickly it'll get a load of petrol from the accelerator pump jets. It does sound like the idle circuits in the carbs are blocked. What does it run like with the central idle circuit on the left hand carb switched off?
Yes slow ones are bad. All jets were cleaned out weekend before last. If you get revs above 1200 it runs rough. And dies out. I checked all the valves on carb and all ok.
If you've ruled out the carbs then then the next thing to test must be the sparks. Are the plug leads definitely on in the right order? Are all the plug leads ok? Pull one off at a time and see if the revs drop. Maybe try a new coil.
It did it before hence carb removal , I am going to start from scratch and replace fuel pipe re clean carbs and try a dizzy with points instead of pertronix
Just to update my saga. I replaced coil, leads, plugs, leads. Set valve clearances. New fuel line and filters. Did a compression test, re tested carbs again after stripping and cleaning. Checked battery's and charge rate as was not sure on electronic ignition. So today swapped dizzy for one with points and condenser. Now running sweet so mot this week. This is the second time I have had to replace pertronix ignition. Anyone know a better brand Cheers
I blew a Pertronix with the old wire swap trick. Bought an Accuspark off eBay for half the price of the Pertronix. It is as good as Pertronix in all respects and better than the Pertronix in one respect. If the engine stops turning it cuts the current to the coil so the ignition coil does not get hot. They also provide thermal grease to help cool the electronic brick. When I was doing ignition lead pulling to work out which cylinder was not firing the other day the sparks coming off the distributor were jumping at least half an inch as I pulled the lead.
