Runs Rough When Warm
Posted: Mon Oct 03, 2011 6:02 pm
I've looked through the forum but may be slightly off-topic as this is one of those peculiar problems. The car starts OK but runs rough - like a misfire - when warm.
I checked fuel delivery (and for air bubbles) which is all OK. The carb was then dismantled and some rusty deposit cleaned out, but the jet is clear, plunger oil is topped up and there are no manifold leaks. All other things (fuel cap vent etc) fuel wise seem in order.
I then checked the ignition points, as a previous episode of the same symptoms had caused me to replace the dizzy cap, rotor and leads. They seemed to be way too wide, so I reset them at 15 thou. It ran fine so i parked it up, but next day the syptoms returned and worsened as I drove.
After a second carb strip which revelaed no problems there, I found the points had closed up, so I reset them again. It ran ok until warm and the stuttering returned. It occurs to me the previous owner suffered this as he had put new plugs in before letting me collect it. Also, previous experience with a 40 year old motor tells me the distrubutor shaft may be worn. This is a mystical problem, which can cause you to blame other components as the cause is dificult to detect -things seems normal (like points gaps etc) and the nature of the fault hides itself. So before I get a replacement distributor, has anyone any suggestions as to what this may be?
The car ran fine when I bought it but went doolally shortly after. I fixed it (according to the manual revving it with hand over carb clears the jet) and it ran good for a few weeks. I tried this method again and it didn't work, hence other investigations
I checked fuel delivery (and for air bubbles) which is all OK. The carb was then dismantled and some rusty deposit cleaned out, but the jet is clear, plunger oil is topped up and there are no manifold leaks. All other things (fuel cap vent etc) fuel wise seem in order.
I then checked the ignition points, as a previous episode of the same symptoms had caused me to replace the dizzy cap, rotor and leads. They seemed to be way too wide, so I reset them at 15 thou. It ran fine so i parked it up, but next day the syptoms returned and worsened as I drove.
After a second carb strip which revelaed no problems there, I found the points had closed up, so I reset them again. It ran ok until warm and the stuttering returned. It occurs to me the previous owner suffered this as he had put new plugs in before letting me collect it. Also, previous experience with a 40 year old motor tells me the distrubutor shaft may be worn. This is a mystical problem, which can cause you to blame other components as the cause is dificult to detect -things seems normal (like points gaps etc) and the nature of the fault hides itself. So before I get a replacement distributor, has anyone any suggestions as to what this may be?
The car ran fine when I bought it but went doolally shortly after. I fixed it (according to the manual revving it with hand over carb clears the jet) and it ran good for a few weeks. I tried this method again and it didn't work, hence other investigations