QuestionI have a 69 TR6. The hydro carbons are too high at idle. I have checked compresion and they run from 145 to 135 lbs. I have petronix ignition and have installed all new spark plugs.
I had a mechanic work on the carbs but the car has not run well since. It will not idle at a steady rpm. When returning from a high rpm the idle will be higher then will reduce in rpm but then increase again as the engine idles.
I have new carb kits in both of the Zenith CD2 carbs. I have checked and cleaned the temp compensation valves. I checked to see that they are both opening at the same temp. I have used various weight of oil in the dampener. Both metering needles move freely and together. Both main jets are clean and set I have set both float levels at 17 mm. I have checked for vacumn leaks and do not have any.
As for mixture I have set them using the procedure in the Bently manual (which is pretty imprecise).
I do not know what to do next. What can you suggest
AnswerDennis,
I'm guessing you're trying to get past an emissions inspection?
From past experience, in order to get the TR6 to pass it had to be tuned so badly that the car would run poorly... but enough to get to the station, pass the exam and then get home again to be "reset" to a proper running tune.
Then again, an erratic idle points to there being something else not quite right. High hydrocarbon readings are caused by a rich mixture, with the gas not being burned completely in the cylinders.
Have you checked the spark plugs from #1 and #6 cylinder to see if the mixture is the same from both carbs?
Another possibility is a vacuum leak on the lines going to the distributor.
Cheers,
Jim
